To investigate the events involved in regulation of the secretogranin II (SgII) gene, luciferase reporter constructs were transfected into gonadotrope-derived, αT3-1 cells. DNA between -91 and -60 relative to the transcription start site was found to be required for GnRH induced SgII reporter gene activation. This region contains a consensus cAMP response element (CRE) and disruption of this CRE reduced GnRH responsiveness of the SgII promoter. CREB was shown to bind to the SgII CRE and transfection studies with a dominant-negative CREB mutant provided evidence that CREB is required for GnRH responsiveness of the SgII promoter. An expression vector for an inhibitor of the cAMP-dependent protein kinase was found to reduce the ability of cAMP or GnRH to activate the SgII-luciferase reporter gene. These studies offer evidence that GnRH-induced activation of the SgII promoter in the αT3-1 cell line requires cAMP-dependent protein kinase activity and a functional CRE within the 5′-flanking region of the gene.
- Gonadotropin releasing hormone
- Secretogranin II
- cAMP-dependent protein kinase
- cAMP-response element
ASJC Scopus subject areas
- Molecular Biology