Induction of rat p120 gene expression in the ovary. Northern blot analysis of rat p120 mRNA in cultured granulosa cells treated with FSH (a), in immature rat ovary primed with PMSG (b), and in immature rat ovary primed with PMSG followed by hCG (c). Total RNA was isolated at the indicated times after the treatments. All samples contained 10 micrograms of total RNA. The blots were hybridized with each specific probe of rat p120, ER-alpha, ER-beta, or PR, respectively. The blots were striped and rehybridized with a probe specific for GAPDH or 36B4 to normalize for equivalent loading of RNA.