Calcium influx and DREAM protein are required for GnRH gene expression pulse activity.

ABSTRACT: Recent evidence using GT1-7 cells indicates that GnRH pulsatility depends on exocytotic-release and gene transcription events. To determine whether calcium or DREAM may play a role in linking these processes, we used an L-type Ca(2+)-blocker (nimodipine) and found that not only GnRH gene expression (GnRH-GE) pulse activity was abolished but also that binding of proteins to OCT1BS-a (essential site for GnRH-GE pulses) was reduced. We further found that only EF-hand forms of DREAM were expressed in GT1-7 and that DREAM was part of the complex binding to OCT1BS-a. Finally, microinjection of DREAM antibody into cells abolished GnRH-GE pulses demonstrating its importance in pulsatility. These results reveal that calcium and DREAM may bridge cytoplasmic and nuclear events enabling temporal coord

SUBMITTER: Leclerc GM 

PROVIDER: S-EPMC1852481 | biostudies-literature | 2007 Mar

REPOSITORIES: biostudies-literature