Ovary Specific Acidic Protein (OSAP)

Ovary-specific acidic protein (OSAP) is a novel molecule discovered from a genomic project designed to identify ovary-selective genes in mice. OSAP silencing by specific small interfering RNAs significantly inhibits 8-bromoadenosine-cAMP-induced progesterone production in Y-1 cells.Reduction in OSAP levels results in mitochondrial fragmentation and a decrease in the cellular content of mitochondrial DNA, indicative of decreased mitochondrial abundance. Lastly, 8-bromoadenosine-cAMP does not regulate OSAP protein expression in Y-1 cells as is the case for other steroidogenic components known to be induced by cAMP. Collectively these results suggest that OSAP is involved in steroidogenesis, potentially through its ability to maintain mitochondrial abundance and morphology.