Biology:CRYBA4
 Generic protein structure example |
Beta-crystallin A4 is a protein that in humans is encoded by the CRYBA4 gene.[1][2][3]
Crystallins are separated into two classes: taxon-specific, or enzyme, and ubiquitous. The latter class constitutes the major proteins of vertebrate eye lens and maintains the transparency and refractive index of the lens. Since lens central fiber cells lose their nuclei during development, these crystallins are made and then retained throughout life, making them extremely stable proteins.
Mammalian lens crystallins are divided into alpha, beta, and gamma families; beta and gamma crystallins are also considered as a superfamily. Alpha and beta families are further divided into acidic and basic groups. Seven protein regions exist in crystallins: four homologous motifs, a connecting peptide, and N- and C-terminal extensions.
Beta-crystallins, the most heterogeneous, differ by the presence of the C-terminal extension (present in the basic group, none in the acidic group). Beta-crystallins form aggregates of different sizes and are able to self-associate to form dimers or to form heterodimers with other beta-crystallins. This gene, a beta acidic group member, is part of a gene cluster with beta-B1, beta-B2, and beta-B3.[3]
References
- ↑ "Sequence analysis of betaA3, betaB3, and betaA4 crystallins completes the identification of the major proteins in young human lens". J Biol Chem 272 (4): 2268–75. Feb 1997. doi:10.1074/jbc.272.4.2268. PMID 8999933.
- ↑ "[Feral domestic pigeons as a hygienic problem in big cities--the situation in Magdeburg]". Z Gesamte Hyg 22 (1): 30–4. Oct 1976. PMID 960806.
- ↑ 3.0 3.1 "Entrez Gene: CRYBA4 crystallin, beta A4". https://www.ncbi.nlm.nih.gov/sites/entrez?Db=gene&Cmd=ShowDetailView&TermToSearch=1413.
External links
- Human CRYBA4 genome location and CRYBA4 gene details page in the UCSC Genome Browser.
Further reading
- "CRYBA4, a novel human cataract gene, is also involved in microphthalmia.". Am. J. Hum. Genet. 79 (4): 702–9. 2006. doi:10.1086/507712. PMID 16960806.
- "The status, quality, and expansion of the NIH full-length cDNA project: the Mammalian Gene Collection (MGC).". Genome Res. 14 (10B): 2121–7. 2004. doi:10.1101/gr.2596504. PMID 15489334.
- "A genome annotation-driven approach to cloning the human ORFeome.". Genome Biol. 5 (10): R84. 2005. doi:10.1186/gb-2004-5-10-r84. PMID 15461802.
- "Generation and initial analysis of more than 15,000 full-length human and mouse cDNA sequences.". Proc. Natl. Acad. Sci. U.S.A. 99 (26): 16899–903. 2003. doi:10.1073/pnas.242603899. PMID 12477932. Bibcode: 2002PNAS...9916899M.
- "A nonsense mutation in CRYBB1 associated with autosomal dominant cataract linked to human chromosome 22q.". Am. J. Hum. Genet. 71 (5): 1216–21. 2003. doi:10.1086/344212. PMID 12360425.
- "Shotgun identification of protein modifications from protein complexes and lens tissue.". Proc. Natl. Acad. Sci. U.S.A. 99 (12): 7900–5. 2002. doi:10.1073/pnas.122231399. PMID 12060738. Bibcode: 2002PNAS...99.7900M.
- "The DNA sequence of human chromosome 22.". Nature 402 (6761): 489–95. 1999. doi:10.1038/990031. PMID 10591208. Bibcode: 1999Natur.402..489D.
- "Normalization and subtraction: two approaches to facilitate gene discovery.". Genome Res. 6 (9): 791–806. 1997. doi:10.1101/gr.6.9.791. PMID 8889548.
- "Sequence analysis of lens beta-crystallins suggests involvement of calpain in cataract formation.". J. Biol. Chem. 268 (3): 1937–40. 1993. doi:10.1016/S0021-9258(18)53944-2. PMID 8420967.
- "Regional fine mapping of the beta crystallin genes on chromosome 22 excludes these genes as physically linked markers for neurofibromatosis type 2.". Genes Chromosomes Cancer 8 (2): 112–8. 1994. doi:10.1002/gcc.2870080208. PMID 7504514.
- "Localization of the beta A4-crystallin gene (CRYBA4) on human chromosome 22 in the region q11.2→q13.1.". Cytogenet. Cell Genet. 61 (3): 180–3. 1992. doi:10.1159/000133403. PMID 1424806.
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