Gene structure and promoter function of murine Munc18-2, a nonneuronal exocytic Sec1 homolog.
Sec1 family proteins are regulators of diverse exocytic processes, from yeast to man. Three mammalian homologues, Munc18-1, -2, and -3 have been described. We have studied the structure and expression of the mouse Munc18-2 gene. The Munc18-2 gene comprises 19 exons whose sizes range from 50 to 158 bp, with a total gene size of approximately 11 kb. A single transcript of 2.1 kb is expressed in multiple non-neuronal murine tissues. Munc18-2 has a striking resemblance to Munc18-1 in structure despite only 60% sequence identity, suggesting a recent gene duplication event. Analysis of the region upstream of the transcription start site shows that Munc18-2 has a TATA-less promoter, with a consensus initiator (Inr) sequence at the start of transcription, several Sp1 binding sites, and strong promoter activity in RBL-2H3 mast cells. The region from +5 to -430 is more active than +5 to -800, suggesting upstream repressor elements.
Agrawal
A
A
Department of Internal Medicine, Baylor College of Medicine, Houston, Texas, 77030, USA. aagrawal@bcm.tmc.edu
Adachi
R
R
Tuvim
M
M
Yan
X T
XT
Teich
A H
AH
Dickey
B F
BF
D000818:Animals; D001483:Base Sequence; D002460:Cell Line; D003001:Cloning, Molecular; D005091:Exons / Q000235:genetics; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation; D020131:Genes, Duplicate / Q000235:genetics; D017930:Genes, Reporter / Q000235:genetics; D007438:Introns / Q000235:genetics; D008407:Mast Cells / Q000378:metabolism; D051379:Mice; D008969:Molecular Sequence Data; D051938:Munc18 Proteins; D009419:Nerve Tissue Proteins / Q000235:genetics*; D011401:Promoter Regions, Genetic / Q000235:genetics*; D011506:Proteins / Q000235:genetics*; D022821:RNA Splice Sites / Q000235:genetics; D012333:RNA, Messenger / Q000032:analysis / Q000235:genetics; D020218:Response Elements / Q000235:genetics; D012689:Sequence Homology, Nucleic Acid; D016329:Sp1 Transcription Factor / Q000502:physiology; D014162:Transfection; D033921:Vesicular Transport Proteins
D051938:Munc18 Proteins; D009419:Nerve Tissue Proteins; D011506:Proteins; D022821:RNA Splice Sites; D012333:RNA, Messenger; D016329:Sp1 Transcription Factor; C497938:Stxbp1 protein, mouse; C497941:Stxbp2 protein, mouse; D033921:Vesicular Transport Proteins