Biology:Gap junction

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Short description: Cell-cell junction composed of innexins or connexins,
Gap junction
Gap cell junction-en.svg
Vertebrate gap junction
Anatomical terminology

Gap junctions are one of four broad categories of intercellular connections that form between a multitude of animal cell types.[1][2] First photographed around 1952,[3][4] it wasn't until 1969 that gap junctions were referred to as "gap junctions".[5] Named after the 2-4 nm gap they bridged between cell membranes, they had been characterised in more detail by 1967.[6]

Within a gap junction reside protein complexes, referred initially to as "globules", observed to connect one cell to another, and also vesicles within a cell to the outer cell membrane.[7] By 1974 one of the major gap junction proteins was dubbed a "connexin",[8][9] and six connexins were observed to form a channels called a "connexon", due to the connections connexon pairs made between cells. The initial discovery of gap junctions in nerve cells lent credence to their function in transmission of electrical impulses. Experimental confirmation followed with molecules, ions and electrical impulses shown to pass through the connexons which proved to be a generalized regulated gate between cells in gap junctions. A type of hemichannel connexons also form channels to the extracellular regions as well.[10][11][12][13]

More than 26 different connexins are known to comprise gap junctions in various different tissues, and there are at least 12 other components[14] that form the specialized area of membrane called the gap junction complex. These components include the tight junction protein ZO-1 that holds the membranes close together,[15] sodium channels,[16] and aquaporin.[17][18]

The increasing ability to sequence the DNA of organisms also increased the complexity of the gap junction family of proteins. The term connexin was used to describe the gap junction proteins connecting two cells with pores. Sequencing of these pore proteins showed them to be structurally similar between vertebrates and invertebrates but different in sequence.[19] As a result the term "innexin" was used to differentiate invertebrate from vertebrate connexins.[20] While sequencing of invertebrate species is far less complete than for vertebrates, more than 20 innexins have already been uncovered,[21] along with unnexins in parasites and vinnexins in viruses.

A gap junction is less frequently called a nexus or macula communicans. There has been some confusion with gap junctions being related to ephapses in the past. While an ephapse, like a gap junction, involves the transmission of electrical signals, the two are different. Ephaptic coupling involves electrical signals external to the cells. Ephapses are often studied in the context of electrically induced potentials propagated among groups of nerve cell membranes, even in the absence of gap junction communication, with no discrete subcellular structures known.[22][23] Unlike gap junctions, no specific structure related to an ephapse has yet been described so the process of "ephaptic coupling" is often referred to rather than an ephapse.

Structure

Connexon pairing across membranes bridges the gap between two cells and between vesicles to membranes.[7]

In vertebrates, gap junction hemichannels are primarily homo- or hetero-hexamers of connexin proteins. Invertebrate gap junctions comprise proteins from the innexin family. Innexins have no significant sequence homology with connexins.[24] Though differing in sequence to connexins, innexins are similar enough to connexins to state that innexins form gap junctions in vivo in the same way connexins do.[25][26][27] The more recently characterized pannexin family,[28] which was originally thought to form inter-cellular channels (with an amino acid sequence similar to innexins[29]), in fact functions as a single-membrane channel that communicates with the extracellular environment, and has been shown to pass calcium and ATP.[30] This has led to the idea that pannexins may never form intercellular junctions in the same way connexins and innexins do and so should not use the same hemi-channel/channel naming.[31] Others have presented evidence based on genetic sequencing and overall functioning in tissues that pannexins should still be considered part of the gap junction family of proteins despite structural differences in the way function is achieved. They also consider that there are still more groups of connexin orthologs to be discovered.[32]

At gap junctions, the intercellular space is between 2 and 4 nm[33] and hemichannels in the membrane of each cell are aligned with one another.[34]

Gap junction channels formed from two identical hemichannels are called homotypic, while those with differing hemichannels are heterotypic. In turn, hemichannels of uniform protein composition are called homomeric, while those with differing proteins are heteromeric. Channel composition influences the function of gap junction channels and different connexins will not necessarily form heterotypic with all others.[35]

Before innexins and connexins were well characterized, the genes coding for connexin gap junction channels were classified in one of three groups, based on gene mapping and sequence similarity: A, B and C (for example, GJA1, GJC1).[36][37][38] However, connexin genes do not code directly for the expression of gap junction channels; genes can produce only the proteins that make up gap junction channels. An alternative naming system based on this protein's molecular weight is the most widely used (for example: connexin43=GJA1, connexin30.3=GJB4).

Levels of organization

In vertebrates two pairs of six connexin proteins form a connexon. For invertebrates six innexin proteins form an innexon. Otherwise the structure is similar. The term hemichannel when used in this description implies half a gap junction channel.

  1. The connexin genes (DNA) are transcribed to RNA, which is then translated to produce a connexin.
  2. One connexin protein has four transmembrane domains[33][39]
  3. Six connexin proteins create one connexon channel (hemichannel). When different connexin proteins join to form one connexon, it is called a heteromeric connexon.
  4. Two connexons, joined across a cell membrane, comprise a Gap Junction channel.
    When two identical connexons come together to form a Gap junction channel, it is called a homotypic channel. When one homomeric connexon and one heteromeric connexon come together, it is called a heterotypic gap junction channel. When two heteromeric connexons join, it is also called a heterotypic Gap Junction channel.
  5. Gap junction channels (tens to thousands) cluster in areas to enable connexon pairs to form.[40] The macromolecular complex is called a gap junction plaque. Molecules other than connexins are involved in gap junction plaques including zonula occludens-1 (ZO-1) and sodium channels.[15][16]

Properties of connexon pairs

Light microscope images do not allow us to see connexons or innexons themselves but do let us see the fluorescing dye injected into one cell moving into neighboring cells when gap junctions are known to be present.[41]

A connexon or innexon channel pair:

  1. Allows for direct electrical communication between cells, although different hemichannel subunits can impart different single channel conductances, from about 30 pS to 500 pS.
  2. Allows for chemical communication between cells, through the transmission of small second messengers, such as inositol triphosphate (IP3) and calcium (Ca2+),[42] although different hemichannel subunits can impart different selectivity for particular small molecules.
  3. In general, allows transmembrane movement of molecules smaller than 485 daltons[43] (1,100 daltons through invertebrate gap junctions[44]), although different hemichannel subunits may impart different pore sizes and different charge selectivity. Large biomolecules, for example, nucleic acid and protein, are precluded from cytoplasmic transfer between cells through gap junction hemichannel pairs.
  4. Ensures that molecules and current passing through the gap junction do not leak into the intercellular space.

Properties of connexons as hemichannels

Unpaired connexons or innexons can act as hemichannels in a single membrane allowing the cell to exchange molecules directly with the exterior of the cell. It has been shown the connexons would be available to do this prior to being incorporated into the gap junction plaques.[40] Some of the properties of these unpaired connexons include.

  1. Pore or transmembrane channel size is highly variable, in the range of approximately 8-20Å in diameter.[45]
  2. They connect the cytoplasm of the cell to the cell exterior so are thought to be in a closed state by default in order to prevent leakage from the cell.[46][47]
  3. Some connexons respond to external factors by opening up. Mechanical sheer and various diseases can cause this to happen.[48]
  4. Establishing further connexon properties different to those of connexon pairs proves difficult due to separating their effects experimentally in organisms.[48]

Occurrence and distribution

Gap Junctions have been observed in various animal organs and tissues where cells contact each other. From the 1950s to 1970s they were detected in crayfish nerves,[49] rat pancreas, liver, adrenal cortex, epididymis, duodenum, muscle,[50] Daphnia hepatic caecum,[51] Hydra muscle,[52] monkey retina,[53] rabbit cornea,[54] fish blastoderm,[55] frog embryos,[56] rabbit ovary,[57] re-aggregating cells,[58][59] cockroach hemocyte capsules,[60] rabbit skin,[61] chick embryos,[62] human islet of Langerhans,[63] goldfish and hamster pressure sensing acoustico-vestibular receptors,[64] lamprey and tunicate heart,[65][66] rat seminiferous tubules,[67] myometrium,[68] eye lens[69] and cephalopod digestive epithelium.[70] Since the 1970s gap junctions have continued to be found in nearly all animal cells that touch each other. By the 1990s new technology such as confocal microscopy allowed more rapid survey of large areas of tissue. Since the 1970s even tissues that were traditionally considered to possibly have isolated cells such as bone showed that the cells were still connected with gap junctions, however tenuously.[71] Gap junctions appear to be in all animal organs and tissues and it will be interesting to find exceptions to this other than cells not normally in contact with neighboring cells. Adult skeletal muscle is a possible exception. It may be argued that if present in skeletal muscle, gap junctions might propagate contractions in an arbitrary way among cells making up the muscle. At least in some cases this may not be the case as shown in other muscle types that do have gap junctions.[72] An indication of what results from reduction or absence of gap junctions may be found by analysis of cancers[73][74][75] or the aging process.[76]

Cell pannexin tree with white squares having communication proteins yet to be discovered

Since the discovery of innexins, pannexins and unnexins, gaps in our knowledge of intercellular communication are becoming more defined. Innexins look and behave similarly to connexins and so can be seen to fill a similar role to connexins in invertebrates. Pannexins also look individually similar to connexins but unlike connexins do not appear to easily form gap junctions. Connexins have been found in only vertebrata and tunicata of over 20 different major metazoan groups. Innexins and pannexins are far more widespread including innexin homologues in vertebrates.[77][78] The unicellular Trypanosomatidae parasites have unnexin genes presumably to aid in their infection of animals including humans.[79] The even smaller adenovirus has its own "vinnexin",[80] apparently derived from an innexin, to aid its transmission between the virus's hosts. As we learn more the term "Gap Junction" cannot be defined by a single protein such as a connexin. The term gap junction appears to be an accurate description of the regular intercellular gap it was originally coined for rather than a junction defined by a single family of proteins. Interestingly gap junction like structures are found in sponges despite not having pannexins. While we are still at the early stages of understanding the nervous system of a sponge[81] the "gap junctions" of sponges may as yet indicate intercellular communications pathways.[82][83]

Functions

At least five discrete functions have been ascribed to gap junction protein:

  1. Electrical and metabolic coupling between cells
  2. Electrical and metabolic exchange through hemichannels
  3. Tumor suppressor genes (Cx43, Cx32 and Cx36)
  4. Adhesive function independent of conductive gap junction channel (neural migration in neocortex)
  5. Role of carboxyl-terminal in signaling cytoplasmic pathways (Cx43)

In a more general sense gap junctions may be seen to function at the simplest level as a direct cell to cell pathway for electrical currents, small molecules and ions. The control of this communication allows complex downstream effects on multicellular organisms as described below.

Embryonic, organ and tissue development

In the 1980s, more subtle but no less important roles of gap junction communication have been investigated. It was discovered that gap junction communication could be disrupted by adding anti-connexin antibodies into embryonic cells.[84][85] Embryos with areas of blocked gap junctions failed to develop normally. The mechanism by which antibodies blocked the gap junctions was unclear but systematic studies were undertaken to elucidate the mechanism.[86][87] Refinement of these studies showed that gap junctions appeared to be key to development of cell polarity[88] and the left/right symmetry/asymmetry in animals.[89][90] While signaling that determines the position of body organs appears to rely on gap junctions so does the more fundamental differentiation of cells at later stages of embryonic development.[91][92][93][94][95]

Gap junctions were also found to be responsible for the transmission of signals required for drugs to have an effect[96] and conversely some drugs were shown to block gap junction channels.[97]

Gap junctions, the "bystander effect" and disease

Cell death

The "bystander effect" with its connotations of the innocent bystander being killed is also mediated by gap junctions. When cells are compromised due to disease or injury and start to die messages are transmitted to neighboring cells connected to the dying cell by gap junctions. This can cause the otherwise unaffected healthy bystander cells to also die.[98] The bystander effect is, therefore, important to consider in diseased cells, which opened an avenue for more funding and a flourish of research.[99][100][101][102][103][104][105][106][107] Later the bystander effect was also researched with regard to cells damaged by radiation or mechanical injury and therefore wound healing.[108][109][110][111][112] Disease also seems to have an effect on the ability of gap junctions to fulfill their roles in wound healing.[113][114] The oral administration of gap junction blockers to reduce the symptoms of disease in remote parts of the body is slowly becoming a reality.[115]

Tissue restructuring

While there has been a tendency to focus on the bystander effect in disease due to the possibility of therapeutic avenues there is evidence that there is a more central role in normal development of tissues. Death of some cells and their surrounding matrix may be required for a tissue to reach its final configuration and gap junctions also appear essential to this process.[116][117] There are also more complex studies that try to combine our understanding of the simultaneous roles of gap junctions in both wound healing and tissue development.[118][119][120]

Disease

Mutations in connexins have been associated with many diseases in humans including deafness, heart atrial fibrillation/standstill and eye lens cataracts.The study of these mutations has helped clarify some of the functions of connexins.[121][122]

At least in part due hemichannels being a potential open door to the outside of each cell, hemichannels are thought to play a general role the progression and severity of many diseases.[48]

Areas of electrical coupling

Gap junctions electrically and chemically couple cells throughout the body of most animals. Electrical coupling can be relatively fast acting and can be used over short distances within an organism. Tissues in this section have well known functions observed to be coordinated by gap junctions with inter-cellular signaling happening in time frames of micro-seconds or less.

Heart

Effects of perinexal width on ephaptic coupling, for G gap = 0 nS

Gap junctions are particularly important in cardiac muscle: the signal to contract is passed efficiently through gap junctions, allowing the heart muscle cells to contract in unison.The importance is emphasized by a secondary ephaptic pathway for the signal to contract also being associated with the gap junction plaques. This redundancy in signal transmission associated with gap junction plaques is the first to be described and involves sodium channels rather than connexins.[16][123]

The eye lens

Eye lens showing arrangement of fiber cells with photos of gap junction plaques from different regions

Precise control of light refraction, structural dimensions and transparency are key aspects of the eye lens structure that allow focusing by the eye. Transparency is aided by the absence of nerves and blood vessels from the lens so gap junctions are left with a larger loading of intercellular communication then in other tissues reflected in large numbers of gap junctions. The crystallinity of the lens also means the cells and gap junctions are well ordered for systematic mapping of where the gap junction plaques are. As no cells are lost from the lens interior during the life of the animal a complete map of the gap junctions is possible.[124] The associated figure shows how the size, shape and frequency of gap junction plaques change with cell growth. With growth the fiber cell's are progressively isolated from more direct metabolite exchange with the aqueous humor through the capsule and lens epithelium. The isolation correlates with the classical circular shape of larger plaques shown in the yellow zone being disrupted. The requirements for changing the fiber cells morphology requires movements of vesicles through the gap junction plaques at higher frequencies in this area.[125]

Neurons

A gap junction located in neurons is often referred to as an electrical synapse. The electrical synapse was discovered using electrical measurements before the gap junction structure was described. Electrical synapses are present throughout the central nervous system and have been studied specifically in the neocortex, hippocampus, vestibular nucleus, thalamic reticular nucleus, locus coeruleus, inferior olivary nucleus, mesencephalic nucleus of the trigeminal nerve, ventral tegmental area, olfactory bulb, retina and spinal cord of vertebrates.[126]

There has been some observation of weak neuron to glial cell coupling in the locus coeruleus, and in the cerebellum between Purkinje neurons and Bergmann glial cells. It appears that astrocytes are coupled by gap junctions, both to other astrocytes and to oligodendrocytes.[127] Moreover, mutations in the gap junction genes Cx43 and Cx56.6 cause white matter degeneration similar to that observed in Pelizaeus–Merzbacher disease and multiple sclerosis.

Connexin proteins expressed in neuronal gap junctions include:

  1. mCX36
  2. mCX57
  3. mCX45

with mRNAs for at least five other connexins (mCx26, mCx30.2, mCx32, mCx43, mCx47) detected but without immunocytochemical evidence for the corresponding protein within ultrastructurally-defined gap junctions. Those mRNAs appear to be down-regulated or destroyed by micro interfering RNAs (miRNAs) that are cell-type and cell-lineage specific.

Retina

Neurons within the retina show extensive coupling, both within populations of one cell type, and between different cell types.[128]

Uterus

The uterine muscle (myometrium) remains in a quiescent relaxed state during pregnancy to maintain fetal development. Immediately preceding labor, the myometrium transforms into an activated contractile unit by increasing expression of connexin-43 (CX43, aka Gap Junction Alpha-1 protein, GJA1) facilitating gap junction (GJ) formation between individual myometrial cells. Importantly, the formation of GJs promotes communication between neighbouring myocytes, which facilitate the transfer of small molecules such as secondary messengers, metabolites, and small ions for electrical coupling. Consistent with all species, uterine myometrial contractions propagate from spontaneous action potentials as a results of sudden change in plasma membrane permeability which lead to increase of intracellular Ca2+ concentrations, facilitating action potential propagation through electrically coupled cells.[129] It has more recently been discovered that uterine macrophage directly physically couple with uterine myocytes through CX43, transferring Ca²⁺, to promote uterine muscle contraction and excitation during labor onset.[130]

Hemichannel function

Eye lens epithelial cells with gap junctions and hemichannels at the interface with fiber cells.
Eye lens fiber cell ends with gap junctions and hemichannels at the interface with fiber cells.

Hemichannels contribute to "The gap junction cellular internet" and allow the release from cells of ATP, glutamate, NAD+ and prostaglandin E2, which can all act as messengers to cells otherwise disconnected from such messaging.[131] In this sense a gap junction plaque forms a one to one relationship with the a neighboring cell, perhaps daisy chaining many cells together. Hemichannels form a one to many relationship with the surrounding tissue.

On a larger scale, the one to many communication of cells is typically carried out by the vascular and nervous systems. This makes detecting the contribution of hemichannels to extracellular communication more difficult in whole organisms. With the eye lens the vascular and nervous systems are absent making reliance on hemichannels greater and their detection easier. At the interface of the lens with the aqueous humor from where the lens exchanges metabolites both gap junction plaques and more diffuse connexon distribution can be seen in the accompanying micrographs.

Discovery

Form an indicator of function

Well before the demonstration of the "gap" in gap junctions they were seen at the junction of neighboring nerve cells. The close proximity of the neighboring cell membranes at the gap junction led researchers to speculate that they had a role in intercellular communication, in particular the transmission of electrical signals.[49][132][133] Gap junctions were also proven to be electrically rectifying and referred to as an electrical synapse.[134][135] Later it was found that chemicals could also be transported between cells through gap junctions.[136]

Implicit or explicit in most of the early studies is that the area of the gap junction was different in structure to the surrounding membranes in a way that made it look different. The gap junction had been shown to create a micro-environment between the two cells in the extra-cellular space or "gap". This portion of extra-cellular space was somewhat isolated from the surrounding space and also bridged by what we now call connexon pairs which form even more tightly sealed bridges that cross the gap junction gap between two cells. When viewed in the plane of the membrane by freeze-fracture techniques, higher-resolution distribution of connexons within the gap junction plaque is possible.[137]

Connexin free islands are observed in some junctions. The observation was largely without explanation until vesicles were shown by Peracchia using TEM thin sections to be systematically associated with gap junction plaques.[138] Peracchia's study was probably also the first study to describe paired connexon structures, which he called somewhat simply a "globule". Studies showing vesicles associated with gap junctions and proposing the vesicle contents may move across the junction plaques between two cells were rare, as most studies focused on the connexons rather than vesicles. A later study using a combination of microscopy techniques confirmed the early evidence of a probable function for gap junctions in intercellular vesicle transfer. Areas of vesicle transfer were associated with connexin free islands within gap junction plaques.[125] Connexin 43 has been shown to be necessary for the transfer of whole mitochondria to neighboring cells though whether the mitochondria is transferred directly through the membrane or within a vesicle is not determined [139]

Electrical and chemical nerve synapses

Because of the widespread occurrence of gap junctions in cell types other than nerve cells the term gap junction became more generally used than terms such as electrical synapse or nexus. Another dimension in the relationship between nerve cells and gap junctions was revealed by studying chemical synapse formation and gap junction presence. By tracing nerve development in leeches with gap junction expression suppressed it was shown that the bidirectional gap junction (electrical nerve synapse) needs to form between two cells before they can grow to form a unidirectional "chemical nerve synapse".[140] The chemical nerve synapse is the synapse most often truncated to the more ambiguous term "nerve synapse".

Composition

Connexins

The purification[141][142] of the intercellular gap junction plaques enriched in the channel forming protein (connexin) showed a protein forming hexagonal arrays in x-ray diffraction. Now the systematic study and identification of the predominant gap junction protein[143] became possible. Refined ultrastructural studies by TEM[144][145] showed protein occurred in a complementary fashion in both cells participating in a gap junction plaque. The gap junction plaque is a relatively large area of membrane observed in TEM thin section and freeze fracture (FF) seen filled with trans-membrane proteins in both tissues and more gently treated gap junction preparations. With the apparent ability for one protein alone to enable intercellular communication seen in gap junctions[146] the term gap junction tended to become synonymous with a group of assembled connexins though this was not shown in vivo. Biochemical analysis of gap junction rich isolates from various tissues demonstrated a family of connexins.[147][148][149]

Ultrastructure and biochemistry of isolated gap junctions already referenced had indicated the connexins preferentially group in gap junction plaques or domains and connexins were the best characterized constituent. It has been noted that the organisation of proteins into arrays with a gap junction plaque may be significant.[56][150] It is likely this early work was already reflecting the presence of more than just connexins in gap junctions. Combining the emerging fields of freeze-fracture to see inside membranes and immunocytochemistry to label cell components (Freeze-fracture replica immunolabelling or FRIL and thin section immunolabelling) showed gap junction plaques in vivo contained the connexin protein.[151][124] Later studies using immunofluorescence microscopy of larger areas of tissue clarified diversity in earlier results. Gap junction plaques were confirmed to have variable composition being home to connexon and non-connexin proteins as well making the modern usage of the terms "gap junction" and "gap junction plaque" non-interchangeable.[18] To summarize, in early literature the term "gap junction" referred to the regular gap between membranes in vertebrates and non-vertebrates apparently bridged by "globules". The junction correlated with the cell's ability to directly couple with its neighbors through pores in their membranes. Then for a while gap junctions were only referring to a structure that contains connexins and nothing more was thought to be involved. Later the gap junction "plaque" was also found to contain other molecules that helped define it and make it function. So the definition seems now to have come full circle.

The "plaque" or "formation plaque"

File:Connexin43-Modulates-Cell-Polarity-and-Directional-Cell-Migration-by-Regulating-Microtubule-Dynamics-pone.0026379.s004.ogv Early descriptions of "gap junctions", "connexons" or "innexons", did not refer to them as such and many other terms were used. It is likely that "synaptic disks"[152] were an accurate reference to gap junction plaques. While the detailed structure and function of the connexon was described in a limited way at the time the gross "disk" structure was relatively large and easily seen by various TEM techniques. Disks allowed researchers using TEM to easily locate the connexons contained within the disk like patches in vivo and in vitro. The disk or "plaque" appeared to have structural properties different from those imparted by the connexons/innexons alone.[52] It was thought that if the area of membrane in the plaque transmitted signals the area of membrane would have to be sealed in some way to prevent leakage.[153] Later studies showed gap junction plaques are home to non-connexin proteins making the modern usage of the terms "gap junction" and "gap junction plaque" non-interchangeable as the area of the gap junction plaque may contain proteins other than connexins.[18][125] Just as connexins do not always occupy the entire area of the plaque the other components described in the literature may be only long term or short-term residents.[154][35][155]

Studies allowing views inside the plane of the membrane of gap junctions during formation indicated that a "formation plaque" formed between two cells prior to the connexins moving in. They were particle free areas when observed by TEM FF indicating very small or no transmembrane proteins were likely present. Little is known about what structures make up the formation plaque or how the formation plaque's structure changes when connexins and other components move in or out. One of the earlier studies of the formation of small gap junctions describes rows of particles and particle free halos.[156] With larger gap junctions they were described as formation plaques with connexins moving into them. The particulate gap junctions were thought to form 4–6 hours after the formation plaques appeared.[157] How the connexins may be transported to the plaques using tubulin is becoming clearer.[88][158]

The formation plaque and non-connexin part of the classical gap junction plaque have been difficult for early researchers to analyse. It appears in TEM FF and thin section to be a lipid membrane domain that can somehow form a comparatively rigid barrier to other lipids and proteins. There has been indirect evidence for certain lipids being preferentially involved with the formation plaque but this cannot be considered definitive.[159][160] It is difficult to envisage breaking up the membrane to analyse membrane plaques without affecting their composition. By study of connexins still in membranes lipids associated with the connexins have been studied.[161] It was found that specific connexins tended to associate preferentially with specific phospholipids. As formation plaques precede connexins these results still give no certainty as to what is unique about the composition of plaques themselves. Other findings show connexins associate with protein scaffolds used in another junction, the zonula occludens ZO1.[162] While this helps us understand how connexins may be moved into a gap junction formation plaque the composition of the plaque itself is still somewhat sketchy. Some headway on the in vivo composition of the gap junction plaque is being made using TEM FRIL.[154][162]

See also

References

  1. ↑ Kelsell, David P.; Dunlop, John; Hodgins, Malcolm B. (2001). "Human diseases: clues to cracking the connexin code?". Trends in Cell Biology 11 (1): 2–6. doi:10.1016/S0962-8924(00)01866-3. PMID 11146276. 
  2. ↑ Willecke, Klaus; Eiberger, Jürgen; Degen, Joachim; Eckardt, Dominik; Romualdi, Alessandro; Güldenagel, Martin; Deutsch, Urban; Söhl, Goran (2002). "Structural and functional diversity of connexin genes in the mouse and human genome". Biological Chemistry 383 (5): 725–37. doi:10.1515/BC.2002.076. PMID 12108537. 
  3. ↑ Robertson, J. D. (1952). Ultrastructure of an invertebrate synapse (Thesis). Cambridge, MA: Massachusetts Institute of Technology.
  4. ↑ Robertson, J. D. (1 February 1953). "Ultrastructure of Two Invertebrate Synapses.". Experimental Biology and Medicine 82 (2): 219–223. doi:10.3181/00379727-82-20071. PMID 13037850. 
  5. ↑ "Junctions between intimately apposed cell membranes in the vertebrate brain". J. Cell Biol. 40 (3): 648–677. March 1969. doi:10.1083/jcb.40.3.648. PMID 5765759. 
  6. ↑ Revel, J. P.; Karnovsky, M. J. (1 June 1967). "Hexagonal Array of Subunits in Intercellular Junctions of the Mouse Heart and Liver". Journal of Cell Biology 33 (3): C7–12. doi:10.1083/jcb.33.3.C7. PMID 6036535. 
  7. ↑ 7.0 7.1 Peracchia, Camillo (1 April 1973). "Low Resistance Junctions in Crayfish". Journal of Cell Biology 57 (1): 66–76. doi:10.1083/jcb.57.1.66. PMID 4120611. 
  8. ↑ Goodenough, Daniel A. (1 May 1974). "Bulk Isolation of Mouse Hepatocyte Gap Junctions". Journal of Cell Biology 61 (2): 557–563. doi:10.1083/jcb.61.2.557. PMID 4363961. 
  9. ↑ Beyer, E C; Paul, D L; Goodenough, D A (1 December 1987). "Connexin43: a protein from rat heart homologous to a gap junction protein from liver.". Journal of Cell Biology 105 (6): 2621–2629. doi:10.1083/jcb.105.6.2621. PMID 2826492. 
  10. ↑ Furshpan, E. J.; Potter, D. D. (August 1957). "Mechanism of Nerve-Impulse Transmission at a Crayfish Synapse". Nature 180 (4581): 342–343. doi:10.1038/180342a0. PMID 13464833. Bibcode: 1957Natur.180..342F. 
  11. ↑ Lampe, Paul D.; Lau, Alan F. (2004). "The effects of connexin phosphorylation on gap junctional communication". The International Journal of Biochemistry & Cell Biology 36 (7): 1171–86. doi:10.1016/S1357-2725(03)00264-4. PMID 15109565. 
  12. ↑ Lampe, Paul D.; Lau, Alan F. (2000). "Regulation of gap junctions by phosphorylation of connexins". Archives of Biochemistry and Biophysics 384 (2): 205–15. doi:10.1006/abbi.2000.2131. PMID 11368307. 
  13. ↑ Scemes, Eliana; Spray, David C.; Meda, Paolo (April 2009). "Connexins, pannexins, innexins: novel roles of "hemi-channels"". Pflügers Archiv: European Journal of Physiology 457 (6): 1207–1226. doi:10.1007/s00424-008-0591-5. PMID 18853183. 
  14. ↑ Hervé, Jean-Claude; Bourmeyster, Nicolas; Sarrouilhe, Denis; Duffy, Heather S. (May 2007). "Gap junctional complexes: From partners to functions". Progress in Biophysics and Molecular Biology 94 (1–2): 29–65. doi:10.1016/j.pbiomolbio.2007.03.010. PMID 17507078. 
  15. ↑ 15.0 15.1 Gilleron, Jérome; Carette, Diane; Fiorini, Céline; Benkdane, Merieme; Segretain, Dominique; Pointis, Georges (March 2009). "Connexin 43 gap junction plaque endocytosis implies molecular remodelling of ZO-1 and c-Src partners". Communicative & Integrative Biology 2 (2): 104–106. doi:10.4161/cib.7626. PMID 19704902. 
  16. ↑ 16.0 16.1 16.2 Ivanovic, Ena; Kucera, Jan P. (November 2021). "Localization of Na + channel clusters in narrowed perinexi of gap junctions enhances cardiac impulse transmission via ephaptic coupling: a model study". The Journal of Physiology 599 (21): 4779–4811. doi:10.1113/JP282105. PMID 34533834. 
  17. ↑ Yu, Xun Sean; Yin, Xinye; Lafer, Eileen M.; Jiang, Jean X. (June 2005). "Developmental Regulation of the Direct Interaction between the Intracellular Loop of Connexin 45.6 and the C Terminus of Major Intrinsic Protein (Aquaporin-0)". Journal of Biological Chemistry 280 (23): 22081–22090. doi:10.1074/jbc.M414377200. PMID 15802270. 
  18. ↑ 18.0 18.1 18.2 Gruijters, WTM (1989). "A non-connexon protein (MIP) is involved in eye lens gap-junction formation". Journal of Cell Science 93 (3): 509–513. doi:10.1242/jcs.93.3.509. PMID 2691517. http://jcs.biologists.org/cgi/content/abstract/93/3/509. 
  19. ↑ Phelan, Pauline; Stebbings, Lucy A.; Baines, Richard A.; Bacon, Jonathan P.; Davies, Jane A.; Ford, Chris (January 1998). "Drosophila Shaking-B protein forms gap junctions in paired Xenopus oocytes". Nature 391 (6663): 181–184. doi:10.1038/34426. PMID 9428764. Bibcode: 1998Natur.391..181P. 
  20. ↑ Phelan, Pauline; Bacon, Jonathan P.; A. Davies, Jane; Stebbings, Lucy A.; Todman, Martin G. (September 1998). "Innexins: a family of invertebrate gap-junction proteins". Trends in Genetics 14 (9): 348–349. doi:10.1016/s0168-9525(98)01547-9. PMID 9769729. 
  21. ↑ Ortiz, Jennifer; Bobkov, Yuriy V; DeBiasse, Melissa B; Mitchell, Dorothy G; Edgar, Allison; Martindale, Mark Q; Moss, Anthony G; Babonis, Leslie S et al. (3 February 2023). "Independent Innexin Radiation Shaped Signaling in Ctenophores". Molecular Biology and Evolution 40 (2): msad025. doi:10.1093/molbev/msad025. PMID 36740225. 
  22. ↑ Martinez-Banaclocha, Marcos (13 February 2020). "Astroglial Isopotentiality and Calcium-Associated Biomagnetic Field Effects on Cortical Neuronal Coupling". Cells 9 (2): 439. doi:10.3390/cells9020439. PMID 32069981. 
  23. ↑ Parker, David (22 December 2022). "Neurobiological reduction: From cellular explanations of behavior to interventions". Frontiers in Psychology 13: 987101. doi:10.3389/fpsyg.2022.987101. PMID 36619115. 
  24. ↑ The C. elegans Sequencing Consortium (Dec 11, 1998). "Genome sequence of the nematode C. elegans: a platform for investigating biology". Science 282 (5396): 2012–2018. doi:10.1126/science.282.5396.2012. PMID 9851916. Bibcode: 1998Sci...282.2012.. 
  25. ↑ Ganfornina, MD; Sánchez, D; Herrera, M; Bastiani, MJ (1999). "Developmental expression and molecular characterization of two gap junction channel proteins expressed during embryogenesis in the grasshopper Schistocerca americana". Developmental Genetics 24 (1–2): 137–150. doi:10.1002/(SICI)1520-6408(1999)24:1/2<137::AID-DVG13>3.0.CO;2-7. PMID 10079517. 
  26. ↑ Starich, T. A. (1996). "eat-5 and unc-7 represent a multigene family in Caenorhabditis elegans involved in cell-cell coupling". J. Cell Biol. 134 (2): 537–548. doi:10.1083/jcb.134.2.537. PMID 8707836. 
  27. ↑ Simonsen, Karina T.; Moerman, Donald G.; Naus, Christian C. (2014). "Gap junctions in C. elegans". Frontiers in Physiology 5: 40. doi:10.3389/fphys.2014.00040. PMID 24575048. 
  28. ↑ Barbe, M. T. (1 April 2006). "Cell-Cell Communication Beyond Connexins: The Pannexin Channels". Physiology 21 (2): 103–114. doi:10.1152/physiol.00048.2005. PMID 16565476. 
  29. ↑ Panchina, Yuri; Kelmanson, Ilya; Matz, Mikhail; Lukyanov, Konstantin; Usman, Natalia; Lukyanov, Sergey (June 2000). "A ubiquitous family of putative gap junction molecules". Current Biology 10 (13): R473–R474. doi:10.1016/S0960-9822(00)00576-5. PMID 10898987. 
  30. ↑ Lohman, Alexander W.; Isakson, Brant E. (2014). "Differentiating connexin hemichannels and pannexin channels in cellular ATP release". FEBS Letters 588 (8): 1379–1388. doi:10.1016/j.febslet.2014.02.004. PMID 24548565. 
  31. ↑ "Pannexin channels are not gap junction hemichannels". Channels 5 (3): 193–197. 2011-05-01. doi:10.4161/chan.5.3.15765. PMID 21532340. 
  32. ↑ Slivko-Koltchik, Georgy A. (2019-02-26). "Are there gap junctions without connexins or pannexins?". BMC Ecol. Evol. 19 (Suppl 1): 46. doi:10.1186/s12862-019-1369-4. PMID 30813901. Bibcode: 2019BMCEE..19S..46S. 
  33. ↑ 33.0 33.1 Maeda, Shoji; Nakagawa, So; Suga, Michihiro; Yamashita, Eiki; Oshima, Atsunori; Fujiyoshi, Yoshinori; Tsukihara, Tomitake (2009). "Structure of the connexin 26 gap junction channel at 3.5 A resolution". Nature 458 (7238): 597–602. doi:10.1038/nature07869. PMID 19340074. Bibcode: 2009Natur.458..597M. 
  34. ↑ Perkins, Guy A.; Goodenough, Daniel A.; Sosinsky, Gina E. (1998). "Formation of the gap junction intercellular channel requires a 30 degree rotation for interdigitating two apposing connexons". Journal of Molecular Biology 277 (2): 171–7. doi:10.1006/jmbi.1997.1580. PMID 9514740. 
  35. ↑ 35.0 35.1 Hervé, JC; Bourmeyster, N; Sarrouilhe, D; Duffy, HS (May 2007). "Gap junctional complexes: from partners to functions.". Prog Biophys Mol Biol 94 (1–2): 29–65. doi:10.1016/j.pbiomolbio.2007.03.010. PMID 17507078. 
  36. ↑ Hsieh, CL; Kumar, NM; Gilula, NB; Francke, U (Mar 1991). "Distribution of genes for gap junction membrane channel proteins on human and mouse chromosomes.". Somatic Cell and Molecular Genetics 17 (2): 191–200. doi:10.1007/bf01232976. PMID 1849321. 
  37. ↑ Kumar, NM; Gilula, NB (Feb 1992). "Molecular biology and genetics of gap junction channels.". Seminars in Cell Biology 3 (1): 3–16. doi:10.1016/s1043-4682(10)80003-0. PMID 1320430. 
  38. ↑ Kren, BT; Kumar, NM; Wang, SQ; Gilula, NB; Steer, CJ (Nov 1993). "Differential regulation of multiple gap junction transcripts and proteins during rat liver regeneration.". The Journal of Cell Biology 123 (3): 707–18. doi:10.1083/jcb.123.3.707. PMID 8227133. 
  39. ↑ Oshima, A; Tani, K; Fujiyoshi, Y (1 Dec 2016). "Atomic structure of the innexin-6 gap junction channel determined by cryo-EM.". Nat. Commun. 7: 13681. doi:10.1038/ncomms13681. PMID 27905396. Bibcode: 2016NatCo...713681O. 
  40. ↑ 40.0 40.1 Lauf, Undine; Giepmans, Ben N. G.; Lopez, Patricia; Braconnot, Sébastien; Chen, Shu-Chih; Falk, Matthias M. (6 August 2002). "Dynamic trafficking and delivery of connexons to the plasma membrane and accretion to gap junctions in living cells". Proceedings of the National Academy of Sciences 99 (16): 10446–10451. doi:10.1073/pnas.162055899. PMID 12149451. Bibcode: 2002PNAS...9910446L. 
  41. ↑ Chang, Qing; Tang, Wenxue; Ahmad, Shoeb; Zhou, Binfei; Lin, Xi (2008). Schiffmann, Raphael. ed. "Gap junction mediated intercellular metabolite transfer in the cochlea is compromised in connexin30 null mice". PLOS ONE 3 (12): e4088. doi:10.1371/journal.pone.0004088. PMID 19116647. Bibcode: 2008PLoSO...3.4088C. 
  42. ↑ Alberts, Bruce (2002). Molecular biology of the cell (4th ed.). New York: Garland Science. ISBN 978-0-8153-3218-3. [page needed]
  43. ↑ "Exchange of conductance and gating properties between gap junction hemichannels". FEBS Lett 451 (2): 113–117. 1999. doi:10.1016/S0014-5793(99)00558-X. PMID 10371149. 
  44. ↑ "Permeability of membrane junctions". Ann. N. Y. Acad. Sci. 137 (2): 441–472. July 1966. doi:10.1111/j.1749-6632.1966.tb50175.x. PMID 5229810. Bibcode: 1966NYASA.137..441L. 
  45. ↑ Khan, Ali K.; Jagielnicki, Maciej; Bennett, Brad.C.; Purdy, Michael D.; Yeager, Mark (September 2021). "Cryo-EM structure of an open conformation of a gap junction hemichannel in lipid bilayer nanodiscs". Structure 29 (9): 1040–1047.e3. doi:10.1016/j.str.2021.05.010. PMID 34129834. 
  46. ↑ Goodenough, Daniel A.; Paul, David L. (April 2003). "Beyond the gap: functions of unpaired connexon channels". Nature Reviews Molecular Cell Biology 4 (4): 285–295. doi:10.1038/nrm1072. 
  47. ↑ Laird, Dale W.; Lampe, Paul D. (December 2018). "Therapeutic strategies targeting connexins". Nature Reviews Drug Discovery 17 (12): 905–921. doi:10.1038/nrd.2018.138. PMID 30310236. 
  48. ↑ 48.0 48.1 48.2 Van Campenhout, Raf; Gomes, Ana Rita; De Groof, Timo W.M.; Muyldermans, Serge; Devoogdt, Nick; Vinken, Mathieu (28 March 2021). "Mechanisms Underlying Connexin Hemichannel Activation in Disease". International Journal of Molecular Sciences 22 (7): 3503. doi:10.3390/ijms22073503. PMID 33800706. 
  49. ↑ 49.0 49.1 Robertson, JD (February 1953). "Ultrastructure of two invertebrate synapses". Proceedings of the Society for Experimental Biology and Medicine 82 (2): 219–23. doi:10.3181/00379727-82-20071. PMID 13037850. 
  50. ↑ "Variations in tight and gap junctions in mammalian tissues". J. Cell Biol. 53 (3): 758–76. June 1972. doi:10.1083/jcb.53.3.758. PMID 4337577. 
  51. ↑ Hudspeth, AJ; Revel, JP (Jul 1971). "Coexistence of gap and septate junctions in an invertebrate epithelium". J. Cell Biol. 50 (1): 92–101. doi:10.1083/jcb.50.1.92. PMID 5563454. 
  52. ↑ 52.0 52.1 Hand, AR; Gobel, S (February 1972). "The structural organization of the septate and gap junctions of Hydra". J. Cell Biol. 52 (2): 397–408. doi:10.1083/jcb.52.2.397. PMID 4109925. 
  53. ↑ Raviola, E; Gilula, NB (Jun 1973). "Gap junctions between photoreceptor cells in the vertebrate retina". Proc Natl Acad Sci U S A 70 (6): 1677–81. doi:10.1073/pnas.70.6.1677. PMID 4198274. Bibcode: 1973PNAS...70.1677R. 
  54. ↑ Kreutziger GO (September 1976). "Lateral membrane morphology and gap junction structure in rabbit corneal endothelium". Exp. Eye Res. 23 (3): 285–93. doi:10.1016/0014-4835(76)90129-9. PMID 976372. 
  55. ↑ "Differentiation of the junctional complex of surface cells in the developing Fundulus blastoderm". J. Cell Biol. 48 (3): 455–72. March 1971. doi:10.1083/jcb.48.3.455. PMID 5545331. 
  56. ↑ 56.0 56.1 J. Cell Biol. 1974 Jul;62(1) 32-47.Assembly of gap junctions during amphibian neurulation. Decker RS, Friend DS.
  57. ↑ Albertini, DF; Anderson, E. (Oct 1974). "The appearance and structure of intercellular connections during the ontogeny of the rabbit ovarian follicle with particular reference to gap junctions". J Cell Biol 63 (1): 234–50. doi:10.1083/jcb.63.1.234. PMID 4417791. 
  58. ↑ "Gap junction formation between reaggregated Novikoff hepatoma cells". Proc. Natl. Acad. Sci. U.S.A. 71 (11): 4536–40. November 1974. doi:10.1073/pnas.71.11.4536. PMID 4373716. Bibcode: 1974PNAS...71.4536J. 
  59. ↑ Knudsen, KA; Horwitz, AF (1978). "Toward a mechanism of myoblast fusion". Prog Clin Biol Res 23: 563–8. PMID 96453. 
  60. ↑ Baerwald RJ (1975). "Inverted gap and other cell junctions in cockroach hemocyte capsules: a thin section and freeze-fracture study". Tissue Cell 7 (3): 575–85. doi:10.1016/0040-8166(75)90027-0. PMID 1179417. 
  61. ↑ Prutkin L (February 1975). "Mucous metaplasia and gap junctions in the vitamin A acid-treated skin tumor, keratoacanthoma". Cancer Res. 35 (2): 364–9. PMID 1109802. http://cancerres.aacrjournals.org/cgi/pmidlookup?view=long&pmid=1109802. 
  62. ↑ Bellairs, R; Breathnach, AS; Gross, M (Sep 1975). "Freeze-fracture replication of junctional complexes in unincubated and incubated chick embryos". Cell Tissue Res. 162 (2): 235–52. doi:10.1007/BF00209209. PMID 1237352. 
  63. ↑ "Cell contacts in human islets of Langerhans". J. Clin. Endocrinol. Metab. 41 (5): 841–4. November 1975. doi:10.1210/jcem-41-5-841. PMID 1102552. http://jcem.endojournals.org/cgi/pmidlookup?view=long&pmid=1102552. [yes|permanent dead link|dead link}}]
  64. ↑ "Gap junctions between the supporting cells in some acoustico-vestibular receptors". J. Neurocytol. 6 (1): 1–12. February 1977. doi:10.1007/BF01175410. PMID 839246. 
  65. ↑ Shibata, Y; Yamamoto, T (March 1977). "Gap junctions in the cardiac muscle cells of the lamprey". Cell Tissue Res. 178 (4): 477–82. doi:10.1007/BF00219569. PMID 870202. 
  66. ↑ Lorber, V; Rayns, DG (April 1977). "Fine structure of the gap junction in the tunicate heart". Cell Tissue Res. 179 (2): 169–75. doi:10.1007/BF00219794. PMID 858161. 
  67. ↑ "Intercellular junctional complexes of the rat seminiferous tubules: a freeze-fracture study". Anat. Rec. 189 (2): 211–31. October 1977. doi:10.1002/ar.1091890208. PMID 911045. 
  68. ↑ Garfield, RE; Sims, SM; Kannan, MS; Daniel, EE (November 1978). "Possible role of gap junctions in activation of myometrium during parturition". Am. J. Physiol. 235 (5): C168–79. doi:10.1152/ajpcell.1978.235.5.C168. PMID 727239. 
  69. ↑ Goodenough, DA (November 1979). "Lens gap junctions: a structural hypothesis for nonregulated low-resistance intercellular pathways". Invest. Ophthalmol. Vis. Sci. 18 (11): 1104–22. PMID 511455. 
  70. ↑ Boucaud-Camou, Eve (1980). "Junctional structures in digestive epithelia of a cephalopod". Tissue Cell 12 (2): 395–404. doi:10.1016/0040-8166(80)90013-0. PMID 7414602. 
  71. ↑ "The incidence and size of gap junctions between the bone cells in rat calvaria". Anat. Embryol. 187 (4): 343–52. April 1993. doi:10.1007/BF00185892. PMID 8390141. 
  72. ↑ Sperelakis, Nicholas; Ramasamy, Lakshminarayanan (2005). "Gap-junction channels inhibit transverse propagation in cardiac muscle". Biomed Eng Online 4 (1): 7. doi:10.1186/1475-925X-4-7. PMID 15679888. 
  73. ↑ "Intercellular communication and tissue growth: IX. Junctional membrane structure of hybrids between communication-competent and communication-incompetent cells". J. Membr. Biol. 34 (1): 39–54. June 1977. doi:10.1007/BF01870292. PMID 561191. 
  74. ↑ "Comparison of contact-mediated communication in normal and transformed human cells in culture". Proc. Natl. Acad. Sci. U.S.A. 74 (10): 4476–80. October 1977. doi:10.1073/pnas.74.10.4476. PMID 270694. Bibcode: 1977PNAS...74.4476C. 
  75. ↑ Habermann, H; Chang, WY; Birch, L; Mehta, P; Prins, GS (January 2001). "Developmental exposure to estrogens alters epithelial cell adhesion and gap junction proteins in the adult rat prostate". Endocrinology 142 (1): 359–69. doi:10.1210/endo.142.1.7893. PMID 11145599. 
  76. ↑ Kelley, Robert O.; Vogel, Kathryn G.; Crissman, Harry A.; Lujan, Christopher J.; Skipper, Betty E. (March 1979). "Development of the aging cell surface. Reduction of gap junction-mediated metabolic cooperation with progressive subcultivation of human embryo fibroblasts (IMR-90)". Exp. Cell Res. 119 (1): 127–43. doi:10.1016/0014-4827(79)90342-2. PMID 761600. 
  77. ↑ Phelan, Pauline (June 2005). "Innexins: members of an evolutionarily conserved family of gap-junction proteins". Biochimica et Biophysica Acta (BBA) - Biomembranes 1711 (2): 225–245. doi:10.1016/j.bbamem.2004.10.004. PMID 15921654. 
  78. ↑ Hervé, Jean-Claude; Phelan, Pauline; Bruzzone, Roberto; White, Thomas W. (December 2005). "Connexins, innexins and pannexins: Bridging the communication gap". Biochimica et Biophysica Acta (BBA) - Biomembranes 1719 (1–2): 3–5. doi:10.1016/j.bbamem.2005.11.013. PMID 16359939. 
  79. ↑ Güiza, Juan; García, Aníbal; Arriagada, Javiera; Gutiérrez, Camila; González, Jorge; Márquez-Miranda, Valeria; Alegría-Arcos, Melissa; Duarte, Yorley et al. (February 2022). "Unnexins: Homologs of innexin proteins in Trypanosomatidae parasites". Journal of Cellular Physiology 237 (2): 1547–1560. doi:10.1002/jcp.30626. PMID 34779505. 
  80. ↑ Turnbull, Matthew W.; Volkoff, Anne-Nathalie; Webb, Bruce A.; Phelan, Pauline (July 2005). "Functional gap junction genes are encoded by insect viruses". Current Biology 15 (13): R491–R492. doi:10.1016/j.cub.2005.06.052. PMID 16005277. 
  81. ↑ Moroz, Leonid L.; Romanova, Daria Y. (23 December 2022). "Alternative neural systems: What is a neuron? (Ctenophores, sponges and placozoans)". Frontiers in Cell and Developmental Biology 10: 1071961. doi:10.3389/fcell.2022.1071961. PMID 36619868. 
  82. ↑ Bergquist, P.R.; Green, C.R. (1977). "An ultrastructural study of settlement and metamorphosis in sponge larvae". Cah. Biol. Mar. 18: 289–302. 
  83. ↑ Green, C.R.; Bergquist, P.R. (1979). "Cell membrane specializations in the Porifera". Coll Int Cent Natn Res Scient 291: 153–158. 
  84. ↑ Warner, Anne E.; Guthrie, Sarah C.; Gilula, Norton B. (1984). "Antibodies to gap-junctional protein selectively disrupt junctional communication in the early amphibian embryo". Nature 311 (5982): 127–31. doi:10.1038/311127a0. PMID 6088995. Bibcode: 1984Natur.311..127W. 
  85. ↑ Warner, AE (2007). "The Use of Antibodies to Gap Junction Protein to Explore the Role of Gap Junctional Communication During Development". Ciba Foundation Symposium 125 - Junctional Complexes of Epithelial Cells. Novartis Foundation Symposia. 125. 154–67. doi:10.1002/9780470513408.ch10. ISBN 9780470513408. 
  86. ↑ Bastide, B; Jarry-Guichard, T; Briand, JP; Délèze, J; Gros, D (April 1996). "Effect of antipeptide antibodies directed against three domains of connexin43 on the gap junctional permeability of cultured heart cells". J. Membr. Biol. 150 (3): 243–53. doi:10.1007/s002329900048. PMID 8661989. 
  87. ↑ Hofer, A; Dermietzel, R (September 1998). "Visualization and functional blocking of gap junction hemichannels (connexons) with antibodies against external loop domains in astrocytes". Glia 24 (1): 141–54. doi:10.1002/(SICI)1098-1136(199809)24:1<141::AID-GLIA13>3.0.CO;2-R. PMID 9700496. 
  88. ↑ 88.0 88.1 88.2 Brandner, Johanna M, ed (2011). "Connexin43 modulates cell polarity and directional cell migration by regulating microtubule dynamics". PLOS ONE 6 (10): e26379. doi:10.1371/journal.pone.0026379. PMID 22022608. Bibcode: 2011PLoSO...626379F. 
  89. ↑ Levin, Michael; Mercola, Mark (November 1998). "Gap junctions are involved in the early generation of left-right asymmetry". Dev. Biol. 203 (1): 90–105. doi:10.1006/dbio.1998.9024. PMID 9806775. 
  90. ↑ Levin, M; Mercola, M (November 1999). "Gap junction-mediated transfer of left-right patterning signals in the early chick blastoderm is upstream of Shh asymmetry in the node". Development 126 (21): 4703–14. doi:10.1242/dev.126.21.4703. PMID 10518488. 
  91. ↑ Bani-Yaghoub, Mahmud; Underhill, T. Michael; Naus, Christian C.G. (1999). "Gap junction blockage interferes with neuronal and astroglial differentiation of mouse P19 embryonal carcinoma cells". Dev. Genet. 24 (1–2): 69–81. doi:10.1002/(SICI)1520-6408(1999)24:1/2<69::AID-DVG8>3.0.CO;2-M. PMID 10079512. 
  92. ↑ Bani-Yaghoub, Mahmud; Bechberger, John F.; Underhill, T. Michael; Naus, Christian C. G. (March 1999). "The effects of gap junction blockage on neuronal differentiation of human NTera2/clone D1 cells". Exp. Neurol. 156 (1): 16–32. doi:10.1006/exnr.1998.6950. PMID 10192774. 
  93. ↑ Donahue, HJ; Li, Z; Zhou, Z; Yellowley, CE (February 2000). "Differentiation of human fetal osteoblastic cells and gap junctional intercellular communication". Am. J. Physiol., Cell Physiol. 278 (2): C315–22. doi:10.1152/ajpcell.2000.278.2.C315. PMID 10666026. 
  94. ↑ Cronier, L; Frendo, JL; Defamie, N; Pidoux, G; Bertin, G; Guibourdenche, J; Pointis, G; Malassine, A (November 2003). "Requirement of gap junctional intercellular communication for human villous trophoblast differentiation". Biol. Reprod. 69 (5): 1472–80. doi:10.1095/biolreprod.103.016360. PMID 12826585. 
  95. ↑ El-Sabban, ME; Sfeir, AJ; Daher, MH; Kalaany, NY; Bassam, RA; Talhouk, RS (September 2003). "ECM-induced gap junctional communication enhances mammary epithelial cell differentiation". J. Cell Sci. 116 (Pt 17): 3531–41. doi:10.1242/jcs.00656. PMID 12893812. 
  96. ↑ Chaytor, AT; Martin, PE; Evans, WH; Randall, MD; Griffith, TM (October 1999). "The endothelial component of cannabinoid-induced relaxation in rabbit mesenteric artery depends on gap junctional communication". J. Physiol. 520 (2): 539–50. doi:10.1111/j.1469-7793.1999.00539.x. PMID 10523421. 
  97. ↑ Srinivas, M; Hopperstad, MG; Spray, DC (September 2001). "Quinine blocks specific gap junction channel subtypes". Proc. Natl. Acad. Sci. U.S.A. 98 (19): 10942–7. doi:10.1073/pnas.191206198. PMID 11535816. Bibcode: 2001PNAS...9810942S. 
  98. ↑ Li Bi, Wan; Parysek, Linda M.; Warnick, Ronald; Stambrook, Peter J. (December 1993). "In vitro evidence that metabolic cooperation is responsible for the bystander effect observed with HSV tk retroviral gene therapy". Hum. Gene Ther. 4 (6): 725–31. doi:10.1089/hum.1993.4.6-725. PMID 8186287. 
  99. ↑ Pitts, JD (November 1994). "Cancer gene therapy: a bystander effect using the gap junctional pathway". Mol. Carcinog. 11 (3): 127–30. doi:10.1002/mc.2940110302. PMID 7945800. 
  100. ↑ Colombo, Bruno M.; Benedetti, Sara; Ottolenghi, Sergio; Mora, Marina; Pollo, Bianca; Poli, Giorgio; Finocchiaro, Gaetano (June 1995). "The "bystander effect": association of U-87 cell death with ganciclovir-mediated apoptosis of nearby cells and lack of effect in athymic mice". Hum. Gene Ther. 6 (6): 763–72. doi:10.1089/hum.1995.6.6-763. PMID 7548276. 
  101. ↑ Fick, James; Barker, Fred G.; Dazin, Paul; Westphale, Eileen M.; Beyer, Eric C.; Israel, Mark A. (November 1995). "The extent of heterocellular communication mediated by gap junctions is predictive of bystander tumor cytotoxicity in vitro". Proc. Natl. Acad. Sci. U.S.A. 92 (24): 11071–5. doi:10.1073/pnas.92.24.11071. PMID 7479939. Bibcode: 1995PNAS...9211071F. 
  102. ↑ Elshami, AA; Saavedra, A; Zhang, H; Kucharczuk, JC; Spray, DC; Fishman, GI; Amin, KM; Kaiser, LR et al. (January 1996). "Gap junctions play a role in the 'bystander effect' of the herpes simplex virus thymidine kinase/ganciclovir system in vitro". Gene Ther. 3 (1): 85–92. PMID 8929915. 
  103. ↑ Mesnil, Marc; Piccoli, Colette; Tiraby, Gerard; Willecke, Klaus; Yamasaki, Hiroshi (March 1996). "Bystander killing of cancer cells by herpes simplex virus thymidine kinase gene is mediated by connexins". Proceedings of the National Academy of Sciences of the United States of America 93 (5): 1831–5. doi:10.1073/pnas.93.5.1831. PMID 8700844. Bibcode: 1996PNAS...93.1831M. 
  104. ↑ Shinoura, Nobusada; Chen, Lin; Wani, Maqsood A.; Kim, Young Gyu; Larson, Jeffrey J.; Warnick, Ronald E.; Simon, Matthias; Menon, Anil G. et al. (May 1996). "Protein and messenger RNA expression of connexin43 in astrocytomas: implications in brain tumor gene therapy". J. Neurosurg. 84 (5): 839–45; discussion 846. doi:10.3171/jns.1996.84.5.0839. PMID 8622159. 
  105. ↑ Hamel, W; Magnelli, L; Chiarugi, VP; Israel, MA (June 1996). "Herpes simplex virus thymidine kinase/ganciclovir-mediated apoptotic death of bystander cells". Cancer Res. 56 (12): 2697–702. PMID 8665496. 
  106. ↑ Sacco, MG; Benedetti, S; Duflot-Dancer, A; Mesnil, M; Bagnasco, L; Strina, D; Fasolo, V; Villa, A et al. (December 1996). "Partial regression, yet incomplete eradication of mammary tumors in transgenic mice by retrovirally mediated HSVtk transfer 'in vivo'". Gene Ther. 3 (12): 1151–6. PMID 8986442. 
  107. ↑ Ripps, Harris (March 2002). "Cell death in retinitis pigmentosa: gap junctions and the 'bystander' effect". Exp. Eye Res. 74 (3): 327–36. doi:10.1006/exer.2002.1155. PMID 12014914. 
  108. ↑ Little, JB; Azzam, EI; De Toledo, SM; Nagasawa, H (2002). "Bystander effects: intercellular transmission of radiation damage signals". Radiat Prot Dosimetry 99 (1–4): 159–62. doi:10.1093/oxfordjournals.rpd.a006751. PMID 12194273. 
  109. ↑ Zhou, H; Randers-Pehrson, G; Suzuki, M; Waldren, CA; Hei, TK (2002). "Genotoxic damage in non-irradiated cells: contribution from the bystander effect". Radiat Prot Dosimetry 99 (1–4): 227–32. doi:10.1093/oxfordjournals.rpd.a006769. PMID 12194291. 
  110. ↑ Lorimore, SA; Wright, EG (January 2003). "Radiation-induced genomic instability and bystander effects: related inflammatory-type responses to radiation-induced stress and injury? A review". Int. J. Radiat. Biol. 79 (1): 15–25. doi:10.1080/0955300021000045664. PMID 12556327. 
  111. ↑ Ehrlich, HP; Diez, T (2003). "Role for gap junctional intercellular communications in wound repair". Wound Repair Regen 11 (6): 481–9. doi:10.1046/j.1524-475X.2003.11616.x. PMID 14617290. 
  112. ↑ Coutinho, P.; Qiu, C.; Frank, S.; Wang, C.M.; Brown, T.; Green, C.R.; Becker, D.L. (July 2005). "Limiting burn extension by transient inhibition of Connexin43 expression at the site of injury". Br J Plast Surg 58 (5): 658–67. doi:10.1016/j.bjps.2004.12.022. PMID 15927148. 
  113. ↑ Wang, C. M.; Lincoln, J.; Cook, J. E.; Becker, D. L. (November 2007). "Abnormal connexin expression underlies delayed wound healing in diabetic skin". Diabetes 56 (11): 2809–17. doi:10.2337/db07-0613. PMID 17717278. 
  114. ↑ Rivera, EM; Vargas, M; Ricks-Williamson, L (1997). "Considerations for the aesthetic restoration of endodontically treated anterior teeth following intracoronal bleaching". Pract Periodontics Aesthet Dent 9 (1): 117–28. PMID 9550065. 
  115. ↑ Mugisho, Odunayo O.; Aryal, Jyoti; Shorne, Avik; Lyon, Heather; Acosta, Monica L.; Green, Colin R.; Rupenthal, Ilva D. (15 February 2023). "Orally Delivered Connexin43 Hemichannel Blocker, Tonabersat, Inhibits Vascular Breakdown and Inflammasome Activation in a Mouse Model of Diabetic Retinopathy". International Journal of Molecular Sciences 24 (4): 3876. doi:10.3390/ijms24043876. PMID 36835288. 
  116. ↑ Cusato, K; Bosco, A; Rozental, R; Guimarães, CA; Reese, BE; Linden, R; Spray, DC (July 2003). "Gap junctions mediate bystander cell death in developing retina". J. Neurosci. 23 (16): 6413–22. doi:10.1523/JNEUROSCI.23-16-06413.2003. PMID 12878681. 
  117. ↑ Moyer, Kurtis E.; Saggers, Gregory C.; Ehrlich, H. Paul (2004). "Mast cells promote fibroblast populated collagen lattice contraction through gap junction intercellular communication". Wound Repair Regen 12 (3): 269–75. doi:10.1111/j.1067-1927.2004.012310.x. PMID 15225205. 
  118. ↑ Djalilian, A. R.; McGaughey, D; Patel, S; Seo, EY; Yang, C; Cheng, J; Tomic, M; Sinha, S et al. (May 2006). "Connexin 26 regulates epidermal barrier and wound remodeling and promotes psoriasiform response". J. Clin. Invest. 116 (5): 1243–53. doi:10.1172/JCI27186. PMID 16628254. 
  119. ↑ Zhang, Y.; Wang, H.; Kovacs, A.; Kanter, E. M.; Yamada, K. A. (February 2010). "Reduced expression of Cx43 attenuates ventricular remodeling after myocardial infarction via impaired TGF-beta signaling". Am. J. Physiol. Heart Circ. Physiol. 298 (2): H477–87. doi:10.1152/ajpheart.00806.2009. PMID 19966054. 
  120. ↑ "TLR2 mediates gap junctional intercellular communication through connexin-43 in intestinal epithelial barrier injury". J. Biol. Chem. 284 (33): 22332–43. August 2009. doi:10.1074/jbc.M901619200. PMID 19528242. 
  121. ↑ Srinivas, Miduturu; Verselis, Vytas K.; White, Thomas W. (1 January 2018). "Human diseases associated with connexin mutations". Biochimica et Biophysica Acta (BBA) - Biomembranes 1860 (1): 192–201. doi:10.1016/j.bbamem.2017.04.024. PMID 28457858. 
  122. ↑ White, Thomas W.; Paul, David L. (1999). "Genetic diseases and gene knockouts reveal diverse connexin functions". Annual Review of Physiology 61 (1): 283–310. doi:10.1146/annurev.physiol.61.1.283. PMID 10099690. 
  123. ↑ Ivanovic, Ena; Kucera, Jan P. (2 November 2022). "Tortuous Cardiac Intercalated Discs Modulate Ephaptic Coupling". Cells 11 (21): 3477. doi:10.3390/cells11213477. PMID 36359872. 
  124. ↑ 124.0 124.1 Gruijters, W.T.; Kistler, J.; Bullivant, S. (1 October 1987). "Formation, distribution and dissociation of intercellular junctions in the lens". Journal of Cell Science 88 (3): 351–359. doi:10.1242/jcs.88.3.351. 
  125. ↑ 125.0 125.1 125.2 Gruijters, W (2003). "Are gap junction membrane plaques implicated in intercellular vesicle transfer?". Cell Biology International 27 (9): 711–717. doi:10.1186/s12862-019-1369-4. PMID 30813901. Bibcode: 2019BMCEE..19S..46S. 
  126. ↑ Connors; Long (2004). "Electrical synapses in the mammalian brain". Annu Rev Neurosci 27: 393–418. doi:10.1146/annurev.neuro.26.041002.131128. PMID 15217338. https://zenodo.org/record/894386. 
  127. ↑ Orthmann-Murphy, Jennifer L.; Abrams, Charles K.; Scherer, Steven S. (May 2008). "Gap Junctions Couple Astrocytes and Oligodendrocytes". Journal of Molecular Neuroscience 35 (1): 101–116. doi:10.1007/s12031-007-9027-5. PMID 18236012. 
  128. ↑ Béla Völgyi; Stewart A. Bloomfield (February 2009). "The diverse functional roles and regulation of neuronal gap junctions in the retina". Nature Reviews Neuroscience 10 (7): 495–506. doi:10.1016/S0165-0173(99)00070-3. PMID 19491906. 
  129. ↑ Garfield, RE; Sims, SM; Kannan, MS; Daniel, EE (November 1978). "Possible role of gap junctions in activation of myometrium during parturition". Am. J. Physiol. 235 (5): C168–79. doi:10.1152/ajpcell.1978.235.5.C168. PMID 727239. S2CID [https://www.semanticscholar.org/paper/Possible-role-of-gap-junctions-in-activation-of-Garfield-Sims/ce78aa441efb2f15ff4749d082197ed4db1b2584 31610495
  130. ↑ Boros-Rausch, A., Shynlova, O., & Lye, S. J. (2021). "A Broad-Spectrum Chemokine Inhibitor Blocks Inflammation-Induced Myometrial Myocyte-Macrophage Crosstalk and Myometrial Contraction". Cells. 11 (1): 128. doi: 10.3390/cells11010128 PMID 35011690
  131. ↑ Evans, W. Howard; De Vuyst, Elke; Leybaert, Luc (1 July 2006). "The gap junction cellular internet: connexin hemichannels enter the signalling limelight". Biochemical Journal 397 (1): 1–14. doi:10.1042/BJ20060175. PMID 16761954. 
  132. ↑ Robertson, J. D. (1963). Locke, Michael. ed. Cellular membranes in development. New York: Academic Press. OCLC 261587041. [page needed]
  133. ↑ Robertson (1981). "Membrane structure". The Journal of Cell Biology 91 (3): 189s–204s. doi:10.1083/jcb.91.3.189s. PMID 7033238. 
  134. ↑ "Mechanism of Nerve-Impulse Transmission at a Crayfish Synapse". Nature 180 (4581): 342–343. 1957. doi:10.1038/180342a0. PMID 13464833. Bibcode: 1957Natur.180..342F. 
  135. ↑ "Transmission at the giant motor synapses of the crayfish". The Journal of Physiology 145 (2): 289–325. 1959. doi:10.1113/jphysiol.1959.sp006143. PMID 13642302. 
  136. ↑ Payton, B. W.; Bennett, M. V. L.; Pappas, G. D. (December 1969). "Permeability and structure of junctional membranes at an electrotonic synapse". Science 166 (3913): 1641–1643. doi:10.1126/science.166.3913.1641. PMID 5360587. Bibcode: 1969Sci...166.1641P. 
  137. ↑ Chalcroft, J. P.; Bullivant, S (October 1970). "An interpretation of liver cell membrane and junction structure based on observation of freeze-fracture replicas of both sides of the fracture". J. Cell Biol. 47 (1): 49–60. doi:10.1083/jcb.47.1.49. PMID 4935338. 
  138. ↑ Peracchia, C (April 1973). "Low resistance junctions in crayfish. II. Structural details and further evidence for intercellular channels by freeze-fracture and negative staining". J. Cell Biol. 57 (1): 54–65. doi:10.1083/jcb.57.1.54. PMID 4120610. 
  139. ↑ Islam, M.Expression error: Unrecognized word "et". (2012). "Mitochondrial transfer from bone-marrow–derived stromal cells to pulmonary alveoli protects against acute lung injury.". Nat Med 18 (5): 759–765. doi:10.1038/nm.2736. PMID 22504485. 
  140. ↑ "Gap junction expression is required for normal chemical synapse formation". J. Neurosci. 30 (45): 15277–85. November 2010. doi:10.1523/JNEUROSCI.2331-10.2010. PMID 21068332. 
  141. ↑ Goodenough, D. A.; Stoeckenius, W. (1972). "The isolation of mouse hepatocyte gap junctions : Preliminary Chemical Characterization and X-Ray Diffraction". The Journal of Cell Biology 54 (3): 646–56. doi:10.1083/jcb.54.3.646. PMID 4339819. 
  142. ↑ Goodenough, D. A. (1974). "Bulk isolation of mouse hepatocyte gap junctions : Characterization of the Principal Protein, Connexin". The Journal of Cell Biology 61 (2): 557–63. doi:10.1083/jcb.61.2.557. PMID 4363961. 
  143. ↑ Kumar, N. M.; Gilula, NB (1986). "Cloning and characterization of human and rat liver cDNAs coding for a gap junction protein". The Journal of Cell Biology 103 (3): 767–76. doi:10.1083/jcb.103.3.767. PMID 2875078. 
  144. ↑ "The ultrastructure of the nexus. A correlated thin-section and freeze-cleave study". J. Cell Biol. 47 (3): 666–88. December 1970. doi:10.1083/jcb.47.3.666. PMID 5531667. 
  145. ↑ Chalcroft, J. P.; Bullivant, S (1970). "An interpretation of liver cell membrane and junction structure based on observation of freeze-fracture replicas of both sides of the fracture". The Journal of Cell Biology 47 (1): 49–60. doi:10.1083/jcb.47.1.49. PMID 4935338. 
  146. ↑ Young; Cohn, ZA; Gilula, NB (1987). "Functional assembly of gap junction conductance in lipid bilayers: demonstration that the major 27 kd protein forms the junctional channel". Cell 48 (5): 733–43. doi:10.1016/0092-8674(87)90071-7. PMID 3815522. 
  147. ↑ "The Mr 28,000 gap junction proteins from rat heart and liver are different but related". The Journal of Biological Chemistry 260 (11): 6514–6517. 1985. doi:10.1016/S0021-9258(18)88810-X. PMID 2987225. http://www.jbc.org/content/260/11/6514.abstract. 
  148. ↑ "Connexin43: a protein from rat heart homologous to a gap junction protein from liver". The Journal of Cell Biology 105 (6 Pt 1): 2621–2629. 1987. doi:10.1083/jcb.105.6.2621. PMID 2826492. 
  149. ↑ "Identification of a 70,000-D protein in lens membrane junctional domains". The Journal of Cell Biology 101 (1): 28–35. 1985. doi:10.1083/jcb.101.1.28. PMID 3891760. 
  150. ↑ "Three types of gap junctions interconnecting intestinal epithelial cells visualized by freeze-etching". Proc. Natl. Acad. Sci. U.S.A. 69 (5): 1318–21. May 1972. doi:10.1073/pnas.69.5.1318. PMID 4504340. Bibcode: 1972PNAS...69.1318S. 
  151. ↑ Gruijters, WTM; Kistler, J; Bullivant, S; Goodenough, DA (1987). "Immunolocalization of MP70 in lens fiber 16-17-nm intercellular junctions". The Journal of Cell Biology 104 (3): 565–72. doi:10.1083/jcb.104.3.565. PMID 3818793. 
  152. ↑ Robertson, JD (October 1963). "The occurrence of a subunit pattern in the unit membranes of club endings in mauthner cell synapses in goldfish brains". J. Cell Biol. 19 (1): 201–21. doi:10.1083/jcb.19.1.201. PMID 14069795. 
  153. ↑ "Studies on an epithelial (gland) cell junction. I. Modifications of surface membrane permeability". J. Cell Biol. 22 (3): 565–86. September 1964. doi:10.1083/jcb.22.3.565. PMID 14206423. 
  154. ↑ 154.0 154.1 Wong, Nai Sum, ed (2011). "The distribution of phosphatidylinositol 4,5-bisphosphate in acinar cells of rat pancreas revealed with the freeze-fracture replica labeling method". PLOS ONE 6 (8): e23567. doi:10.1371/journal.pone.0023567. PMID 21858170. Bibcode: 2011PLoSO...623567O. 
  155. ↑ Strauss, RE; Gourdie, RG (December 2020). "Cx43 and the Actin Cytoskeleton: Novel Roles and Implications for Cell-Cell Junction-Based Barrier Function Regulation". Biomolecules 10 (12): 1656. doi:10.3390/biom10121656. PMID 33321985. 
  156. ↑ Decker, RS; Friend, DS (July 1974). "Assembly of gap junctions during amphibian neurulation". J. Cell Biol. 62 (1): 32–47. doi:10.1083/jcb.62.1.32. PMID 4135001. 
  157. ↑ Decker, RS (June 1976). "Hormonal regulation of gap junction differentiation". J. Cell Biol. 69 (3): 669–85. doi:10.1083/jcb.69.3.669. PMID 1083855. 
  158. ↑ "Dynamic trafficking and delivery of connexons to the plasma membrane and accretion to gap junctions in living cells". Proc. Natl. Acad. Sci. U.S.A. 99 (16): 10446–51. August 2002. doi:10.1073/pnas.162055899. PMID 12149451. Bibcode: 2002PNAS...9910446L. 
  159. ↑ Meyer, R; Malewicz, B; Baumann, WJ; Johnson, RG (June 1990). "Increased gap junction assembly between cultured cells upon cholesterol supplementation". J. Cell Sci. 96 (2): 231–8. doi:10.1242/jcs.96.2.231. PMID 1698798. 
  160. ↑ Johnson, R. G.; Reynhout, J. K.; Tenbroek, E. M.; Quade, B. J.; Yasumura, T.; Davidson, K. G. V.; Sheridan, J. D.; Rash, J. E. (January 2012). "Gap junction assembly: roles for the formation plaque and regulation by the C-terminus of connexin43". Mol. Biol. Cell 23 (1): 71–86. doi:10.1091/mbc.E11-02-0141. PMID 22049024. 
  161. ↑ Locke, Darren; Harris, Andrew L (2009). "Connexin channels and phospholipids: association and modulation". BMC Biol. 7 (1): 52. doi:10.1186/1741-7007-7-52. PMID 19686581. 
  162. ↑ 162.0 162.1 "Connexin45-containing neuronal gap junctions in rodent retina also contain connexin36 in both apposing hemiplaques, forming bihomotypic gap junctions, with scaffolding contributed by zonula occludens-1". J. Neurosci. 28 (39): 9769–89. September 2008. doi:10.1523/JNEUROSCI.2137-08.2008. PMID 18815262. 

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