Forkhead box protein H1 is a protein that in humans is encoded by the FOXH1 gene.

Function

FOXH1 encodes a human homolog of Xenopus forkhead activin signal transducer-1. FOXH1 protein binds SMAD2 and activates an activin response element via binding the DNA motif TGT(G/T)(T/G)ATT. FoxH1 is a transcription factor that contains a conserved function in chordates. FoxH1, acts in combination with other transcription factors, as a critical element of node formation in early embryo development. Specifically, FoxH1 plays a role in anterior/posterior determination during gastrulation. By the third week of gestation, cells of the splanchnic mesoderm have migrated to the superior end of the embryo to form the cardiac crescent. The cardiac crescent forms two heart fields; primary heart field and the secondary heart field. At this point in development, the two heart fields fuse to form a primitive, single-chambered heart referred to as the primary myocardium. The secondary (anterior) heart field of these cardiac crescent cells will give rise to the outflow tract and the right ventricle of the mature heart. A model lacking FoxH1 will form a primary myocardium, undergo some amount of looping, but have undefined right ventricles and outflow tracts.

Interactions

FOXH1 has been shown to interact with DRAP1 and Mothers against decapentaplegic homolog 2.