Biology:UNC13B

Generic protein structure example

Protein unc-13 homolog B is a protein that in humans is encoded by the UNC13B gene.

Function

This gene is expressed in the kidney cortical epithelial cells and is upregulated by hyperglycemia. The encoded protein shares a high level of similarity to the rat homolog, and contains 3 C2 domains and a diacylglycerol-binding C1 domain. Hyperglycemia increases the levels of diacylglycerol, which has been shown to induce apoptosis in cells transfected with this gene and thus contribute to the renal cell complications of hyperglycemia. Studies in other species also indicate a role for this protein in the priming step of synaptic vesicle exocytosis.

Interactions

UNC13B has been shown to interact with:

• DOC2A,
• RIMS1,
• SPTBN2,
• STX1A, and
• STX1B.

Further reading

• "Direct interaction of the rat unc-13 homologue Munc13-1 with the N terminus of syntaxin". J. Biol. Chem. 272 (4): 2520–6. 1997. doi:10.1074/jbc.272.4.2520. PMID 8999968. 
• "Physical and functional interactions of Doc2 and Munc13 in Ca2+-dependent exocytotic machinery". J. Biol. Chem. 272 (26): 16081–4. 1997. doi:10.1074/jbc.272.26.16081. PMID 9195900. 
• "A novel brain-specific isoform of beta spectrin: isolation and its interaction with Munc13". Biochem. Biophys. Res. Commun. 248 (3): 846–51. 1998. doi:10.1006/bbrc.1998.9067. PMID 9704016. 
• "Role of the Doc2α–Munc13–1 interaction in the neurotransmitter release process". Proc. Natl. Acad. Sci. U.S.A. 95 (19): 11418–22. 1998. doi:10.1073/pnas.95.19.11418. PMID 9736751. Bibcode: 1998PNAS...9511418M. 
• "Human munc13 Is a Diacylglycerol Receptor that Induces Apoptosis and May Contribute to Renal Cell Injury in Hyperglycemia". Mol. Biol. Cell 10 (5): 1609–19. 1999. doi:10.1091/mbc.10.5.1609. PMID 10233166. 
• "Transient, phorbol ester-induced DOC2-Munc13 interactions in vivo". J. Biol. Chem. 274 (39): 27347–50. 1999. doi:10.1074/jbc.274.39.27347. PMID 10488064. 
• "Functional interaction of the active zone proteins Munc13-1 and RIM1 in synaptic vesicle priming". Neuron 30 (1): 183–96. 2001. doi:10.1016/S0896-6273(01)00272-0. PMID 11343654. 
• "RIM1alpha forms a protein scaffold for regulating neurotransmitter release at the active zone". Nature 415 (6869): 321–6. 2002. doi:10.1038/415321a. PMID 11797009. Bibcode: 2002Natur.415..321S. 
• "Cast: a novel protein of the cytomatrix at the active zone of synapses that forms a ternary complex with RIM1 and munc13-1". J. Cell Biol. 158 (3): 577–90. 2002. doi:10.1083/jcb.200202083. PMID 12163476. 
• "Regulation of insulin exocytosis by Munc13-1". J. Biol. Chem. 278 (30): 27556–63. 2003. doi:10.1074/jbc.M303203200. PMID 12871971. 
• "The Rab-binding protein Noc2 is associated with insulin-containing secretory granules and is essential for pancreatic beta-cell exocytosis". Mol. Endocrinol. 18 (1): 117–26. 2004. doi:10.1210/me.2003-0300. PMID 14593078. 
• "Sequence Comparison of Human and Mouse Genes Reveals a Homologous Block Structure in the Promoter Regions". Genome Res. 14 (9): 1711–8. 2004. doi:10.1101/gr.2435604. PMID 15342556. 
• "Identification of novel MUNC13-4 mutations in familial haemophagocytic lymphohistiocytosis and functional analysis of MUNC13-4-deficient cytotoxic T lymphocytes". J. Med. Genet. 41 (10): 763–7. 2005. doi:10.1136/jmg.2004.021121. PMID 15466010. 
• "Diacylglycerol-activated Hmunc13 serves as an effector of the GTPase Rab34". Traffic 6 (10): 858–65. 2005. doi:10.1111/j.1600-0854.2005.00321.x. PMID 16138900.