Forkhead (FH) domain found in Forkhead box protein P3 (FOXP3) and similar proteins
FOXP3, also called Scurfin, is a transcriptional regulator which is crucial for the development and inhibitory function of regulatory T-cells (Treg), which are required for maintaining self-tolerance. It may also have intrinsic regulatory function in conventional T (Tconv) cells. A deletion of the Forkhead domain arising from a frame-shift mutation in mouse FOXP3 is linked to the autoimmune disorder scurfy, and a similar congenital disease in humans is known as IPEX (immune dysregulation, polyendocrinopathy, enteropathy, X-linked syndrome). The FH domain is a winged helix DNA-binding domain. FOX transcription factors recognize the core sequence 5'-(A/C)AA(C/T)A-3'.