Presumed effect of the coactivators p/CIP and TIF2 on SF-1 transactivation. (After Borud et al., Ref. ). In the absence of PKA, p/CIP and TIF2 potentiate SF-1 transcriptional activity. When SF-1 is associated to p/CIP, overexpression of PKA induces a marked increase in SF-1 transcriptional activity. On the contrary, PKA overexpression prevents TIF2-dependent potentiation of SF-1 activity. The decrease of TIF2 protein accumulation caused by PKA overexpression may explain these observations. SFRE : SF-1 responsive element.