Transforming growth factor beta-1-induced transcript 1 protein is a protein that in humans is encoded by the TGFB1I1 gene. TGFB1I1 is also sometimes called HIC-5 (Hydrogen Peroxide-Inducible Clone-5) or ARA55 (Androgen Receptor Coactivator 55kDA).

As it's multiple names suggests, TGFB1I1 a protein whose expression is induced by TGFB1 and is both inducible by hydrogen peroxide, and a coactivator of the androgen receptors.

TGFB1I1 plays a role in processes of cell growth, proliferation, migration, differentiation, and senescence in multiple contexts including in cancer. TGFB1I1 is most localized at focal adhesion complexes of cells, although it may be found active in the cytosol, nucleus and cell membrane as well.

Transforming growth factor beta-1-induced transcript 1 plays a role in a number of cell functions. Originally, TGFB1I1 was isolated as a senescence-inducing gene from mouse osteoblastic cells through treatment with transforming growth factor beta-1 and hydrogen peroxide. During this, TGFB1I1 was also being independently discovered by numerous other groups and was characterized as a focal adhesion protein, an androgen and glucocorticoid receptor co-activator, a negative regulator of muscle differentiation, and major player in the recovery of arterial media.

TGFB1I1 has been shown to interact with:

This article incorporates text from the United States National Library of Medicine, which is in the public domain.