Biology:Equilibrative nucleoside transporter 1
Generic protein structure example |
Equilibrative nucleoside transporter 1 (ENT1) is a protein that in humans is encoded by the SLC29A1 gene.[1][2] Multiple alternatively spliced variants, encoding the same protein, have been found for this gene.[3] Expressed on red blood cell surfaces, these variants make up the Augustine blood group system.[4]
Function
This gene is a member of the equilibrative nucleoside transporter family. The gene encodes a transmembrane glycoprotein that localizes to the plasma and mitochondrial membranes and mediates the cellular uptake of nucleosides from the surrounding medium. The protein is categorized as an equilibrative (as opposed to concentrative) transporter that is sensitive to inhibition by nitrobenzylmercaptopurine ribonucleoside (NBMPR). Nucleoside transporters are required for nucleotide synthesis in cells that lack de novo nucleoside synthesis pathways, and are also necessary for the uptake of cytotoxic nucleosides used for cancer and viral chemotherapies.[3]
Genomics
The gene encoding this protein is located on the short arm of chromosome 6 at 6p21.2-p21.1 on the Watson (plus) strand. It is 14,647 bases in length. The encoded protein has 456 amino acid residues with 11 predicted transmembrane domains. The predicted molecular weight is 50.219 kilodaltons. The protein is post translationally glycosylated and expressed in all tissue with the apparent exception of skeletal muscle. The highest levels are found in the liver, heart, testis, spleen, lung, kidney and brain.
Interactive pathway map
Clinical significance
Mutations in this gene have been associated with H syndrome, pigmented hypertrichosis with insulin dependent diabetes and Faisalabad histiocytosis.[5]
Alleles of this gene make up the Augustine blood group system.[4] Some of the four known variants are highly immunogenic and antibodies against them can cause acute hemolytic transfusion reaction and hemolytic disease of the fetus and newborn.[6]
See also
- Solute carrier family
- Equilibrative nucleoside transporters
- Nucleoside transporters
- Augustine blood group system
References
- ↑ "Cloning of a human nucleoside transporter implicated in the cellular uptake of adenosine and chemotherapeutic drugs". Nature Medicine 3 (1): 89–93. January 1997. doi:10.1038/nm0197-89. PMID 8986748.
- ↑ "Assignment of the human equilibrative nucleoside transporter (hENT1) to 6p21.1-p21.2". Genomics 45 (2): 459–60. October 1997. doi:10.1006/geno.1997.4928. PMID 9344680.
- ↑ 3.0 3.1 "Entrez Gene: SLC29A1 solute carrier family 29 (nucleoside transporters), member 1". https://www.ncbi.nlm.nih.gov/sites/entrez?Db=gene&Cmd=ShowDetailView&TermToSearch=2030.
- ↑ 4.0 4.1 "The Augustine blood group system, 48 years in the making". Immunohematology 32 (3): 100–103. 2019. doi:10.21307/immunohematology-2019-053. PMID 27834482.
- ↑ "A mild form of SLC29A3 disorder: a frameshift deletion leads to the paradoxical translation of an otherwise noncoding mRNA splice variant". PLOS ONE 7 (1): e29708. 2012. doi:10.1371/journal.pone.0029708. PMID 22238637. Bibcode: 2012PLoSO...729708B.
- ↑ "An update on the Augustine blood group system". Immunohematology 35 (1): 1–2. 2020. doi:10.21307/immunohematology-2020-001. PMID 30908068.
Further reading
- "Normalization and subtraction: two approaches to facilitate gene discovery". Genome Research 6 (9): 791–806. September 1996. doi:10.1101/gr.6.9.791. PMID 8889548.
- "Molecular cloning and characterization of a nitrobenzylthioinosine-insensitive (ei) equilibrative nucleoside transporter from human placenta". The Biochemical Journal 328 ( Pt 3) (3): 739–43. December 1997. doi:10.1042/bj3280739. PMID 9396714.
- "Human intestinal es nucleoside transporter: molecular characterization and nucleoside inhibitory profiles". Cancer Chemotherapy and Pharmacology 45 (4): 273–8. 2000. doi:10.1007/s002800050040. PMID 10755314.
- "Topology of a human equilibrative, nitrobenzylthioinosine (NBMPR)-sensitive nucleoside transporter (hENT1) implicated in the cellular uptake of adenosine and anti-cancer drugs". The Journal of Biological Chemistry 276 (48): 45270–5. November 2001. doi:10.1074/jbc.M107169200. PMID 11584005.
- "A single glycine mutation in the equilibrative nucleoside transporter gene, hENT1, alters nucleoside transport activity and sensitivity to nitrobenzylthioinosine". Biochemistry 41 (5): 1512–9. February 2002. doi:10.1021/bi015833w. PMID 11814344.
- "Functional and molecular characterization of nucleobase transport by recombinant human and rat equilibrative nucleoside transporters 1 and 2. Chimeric constructs reveal a role for the ENT2 helix 5-6 region in nucleobase translocation". The Journal of Biological Chemistry 277 (28): 24938–48. July 2002. doi:10.1074/jbc.M200966200. PMID 12006583.
- "Potential mechanisms of resistance to cytarabine in AML patients". Leukemia Research 26 (7): 621–9. July 2002. doi:10.1016/S0145-2126(01)00184-9. PMID 12008078.
- "Simultaneous expression of hCNT1-CFP and hENT1-YFP in Madin-Darby canine kidney cells. Localization and vectorial transport studies". The Journal of Biological Chemistry 277 (40): 37711–7. October 2002. doi:10.1074/jbc.M204986200. PMID 12097333.
- "Comparative genomic analysis of equilibrative nucleoside transporters suggests conserved protein structure despite limited sequence identity". Nucleic Acids Research 30 (20): 4339–50. October 2002. doi:10.1093/nar/gkf564. PMID 12384580.
- "Differential expression of human equilibrative nucleoside transporter 1 (hENT1) protein in the Reed-Sternberg cells of Hodgkin's disease". Leukemia & Lymphoma 43 (7): 1435–40. July 2002. doi:10.1080/1042819022386725. PMID 12389626.
- "Localization of human equilibrative nucleoside transporters, hENT1 and hENT2, in renal epithelial cells". American Journal of Physiology. Renal Physiology 284 (5): F902-10. May 2003. doi:10.1152/ajprenal.00215.2002. PMID 12527552.
- "Coupling of CFTR-mediated anion secretion to nucleoside transporters and adenosine homeostasis in Calu-3 cells". The Journal of Membrane Biology 192 (3): 169–79. April 2003. doi:10.1007/s00232-002-1073-x. PMID 12820662.
- "Mitochondrial expression of the human equilibrative nucleoside transporter 1 (hENT1) results in enhanced mitochondrial toxicity of antiviral drugs". The Journal of Biological Chemistry 279 (6): 4490–7. February 2004. doi:10.1074/jbc.M307938200. PMID 14607828.
- "Analysis of a high-throughput yeast two-hybrid system and its use to predict the function of intracellular proteins encoded within the human MHC class III region". Genomics 83 (1): 153–67. January 2004. doi:10.1016/S0888-7543(03)00235-0. PMID 14667819.
- "Mutation of leucine-92 selectively reduces the apparent affinity of inosine, guanosine, NBMPR [S6-(4-nitrobenzyl)-mercaptopurine riboside and dilazep for the human equilibrative nucleoside transporter, hENT1"]. The Biochemical Journal 380 (Pt 1): 131–7. May 2004. doi:10.1042/BJ20031880. PMID 14759222.
This article incorporates text from the United States National Library of Medicine, which is in the public domain.
Original source: https://en.wikipedia.org/wiki/Equilibrative nucleoside transporter 1.
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