Functional RNA which acts as a transcriptional coactivator that selectively enhances steroid receptor-mediated transactivation ligand-independently through a mechanism involving the modulating N-terminal domain (AF-1) of steroid receptors. Also mediates transcriptional coactivation of steroid receptors ligand-dependently through the steroid-binding domain (AF-2). Enhances cellular proliferation and differentiation and promotes apoptosis in vivo. May play a role in tumorigenesis.
Subcellular locations: Nucleus, Cytoplasm
Highly expressed in liver and skeletal muscle and to a lesser extent in brain. Also expressed in both normal and tumorigenic breast epithelial cell lines. Significantly up-regulated in human tumors of the breast, ovary, and uterus.