Class A basic helix-loop-helix protein 15

Class A basic helix-loop-helix protein 15 (bHLHa15) also known as class B basic helix-loop-helix protein 8 (bHLHb8) or muscle, intestine and stomach expression 1 (MIST-1) is a protein that in humans is encoded by the BHLHA15 gene.[5][6][7]

BHLHA15
Identifiers
Aliases	BHLHA15, BHLHB8, MIST1, basic helix-loop-helix family member a15
External IDs	OMIM: 608606 MGI: 891976 HomoloGene: 7838 GeneCards: BHLHA15
Gene location (Human) Chr. Chromosome 7 (human)[1] Band 7q21.3 Start 98,211,427 bp[1] End 98,212,979 bp[1]
Gene location (Mouse) Chr. Chromosome 5 (mouse)[2] Band 5|5 G2 Start 144,190,286 bp[2] End 144,194,441 bp[2]
Gene ontology Molecular function • GO:0001077, GO:0001212, GO:0001213, GO:0001211, GO:0001205 DNA-binding transcription activator activity, RNA polymerase II-specific • DNA binding • RNA polymerase II regulatory region sequence-specific DNA binding • protein homodimerization activity • protein dimerization activity • GO:0001200, GO:0001133, GO:0001201 DNA-binding transcription factor activity, RNA polymerase II-specific Cellular component • cell nucleus Biological process • endoplasmic reticulum unfolded protein response • cell-cell signaling • G-protein coupled receptor signaling pathway • cellular response to glucose starvation • intracellular distribution of mitochondria • regulation of transcription, DNA-templated • cell maturation • transcription from RNA polymerase II promoter • mitochondrial calcium ion transmembrane transport • Golgi organization • glucose homeostasis • transcription, DNA-templated • negative regulation of myotube differentiation • calcium-mediated signaling • positive regulation of transcription from RNA polymerase II promoter Sources:Amigo / QuickGO
Orthologs
Species	Human	Mouse
Entrez	168620	17341
Ensembl	ENSG00000180535	ENSMUSG00000052271
UniProt	Q7RTS1	Q9QYC3
RefSeq (mRNA)	NM_177455	NM_010800
RefSeq (protein)	NP_803238	NP_034930
Location (UCSC)	Chr 7: 98.21 – 98.21 Mb	Chr 5: 144.19 – 144.19 Mb
PubMed search	[3]	[4]
Wikidata
View/Edit Human View/Edit Mouse

Function

bHLHa15 is required developmentally for the proper organization of all protein secreting, serous exocrine glands. In the absence of Mist1, exocrine tissue shows improper organization of organelles, especially the localization of the zymogen granules. The zymogen granules are the vesicles that store enzymes near the plasma membrane for easy release when stimulated. This disorganization caused by the loss of Mist1 leads to increased susceptibility toward pancreatic damage and potentially pancreatic cancer.

References

1. GRCh38: Ensembl release 89: ENSG00000180535 - Ensembl, May 2017
2. GRCm38: Ensembl release 89: ENSMUSG00000052271 - Ensembl, May 2017
3. "Human PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
4. "Mouse PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
5. McLellan AS, Langlands K, Kealey T (Sep 2003). "Exhaustive identification of human class II basic helix-loop-helix proteins by virtual library screening". Mech Dev. 119 Suppl 1: S285–91. doi:10.1016/S0925-4773(03)00130-8. PMID 14516699.
6. Stevens JD, Roalson EH, Skinner MK (Dec 2008). "Phylogenetic and expression analysis of the basic helix-loop-helix transcription factor gene family: genomic approach to cellular differentiation". Differentiation. 76 (9): 1006–22. doi:10.1111/j.1432-0436.2008.00285.x. PMC 5728086. PMID 18557763.
7. "Entrez Gene: BHLHB8 basic helix-loop-helix domain containing, class B, 8".

Further reading

• Lemercier C, To RQ, Swanson BJ, et al. (1997). "Mist1: a novel basic helix-loop-helix transcription factor exhibits a developmentally regulated expression pattern". Dev. Biol. 182 (1): 101–13. doi:10.1006/dbio.1996.8454. PMID 9073453.
• Lemercier C, To RQ, Carrasco RA, Konieczny SF (1998). "The basic helix-loop-helix transcription factor Mist1 functions as a transcriptional repressor of myoD". EMBO J. 17 (5): 1412–22. doi:10.1093/emboj/17.5.1412. PMC 1170489. PMID 9482738.
• Pin CL, Lemercier C, Konieczny SF (2000). "Cloning of the murine Mist1 gene and assignment to mouse chromosome band 5G2-5G3". Cytogenet. Cell Genet. 86 (3–4): 219–22. doi:10.1159/000015342. PMID 10575209.
• Pin CL, Rukstalis JM, Johnson C, Konieczny SF (2001). "The bHLH transcription factor Mist1 is required to maintain exocrine pancreas cell organization and acinar cell identity". J. Cell Biol. 155 (4): 519–30. doi:10.1083/jcb.200105060. PMC 2198859. PMID 11696558.
• McLellan AS, Langlands K, Kealey T (2003). "Exhaustive identification of human class II basic helix-loop-helix proteins by virtual library screening". Gene Expr. Patterns. 2 (3–4): 329–35. doi:10.1016/S0925-4773(02)00390-8. PMID 12617822.
• Zhao Y, Johansson C, Tran T, et al. (2006). "Identification of a basic helix-loop-helix transcription factor expressed in mammary gland alveolar cells and required for maintenance of the differentiated state". Mol. Endocrinol. 20 (9): 2187–98. doi:10.1210/me.2005-0214. PMID 16645041.