Type 2 inositol trisphosphate receptor gene expression in hepatocytes is regulated by cyclic AMP.

ABSTRACT: The type 2 inositol 1,4,5-trisphosphate receptor (IP3R2) is the principal intracellular Ca²⁺ release channel in hepatocytes, and so is important for bile secretion and other functions. IP3R2 activity is regulated in part by post-translational modifications but little is known about transcriptional regulation of its expression. We found that both IP3R2 mRNA and protein levels in liver were increased during fasting. Treatment of hepatocytes with forskolin or 8-CPT-cAMP also increased IP3R2, and this was reduced by actinomycin D. Analysis of the IP3R2 promoter revealed five CREs, and CREB potently increased promoter activity. Mutation of CRE4 or CRE5 decreased induction by CREB, and ChIP assay showed recruitment of CREB to these sites. Adenylyl cyclase (AC) 6 and 9 were the princip

SUBMITTER: Kruglov E 

PROVIDER: S-EPMC5421629 | biostudies-literature | 2017 May

REPOSITORIES: biostudies-literature