IRS-4 Antibody

The family of insulin receptor substrates (IRS) has been reported to play an important role for signal transduction of various hormones. Four members of the IRS family have been described. Each IRS is believed to have different functions although the distinct physiological roles of each IRS are unclear. IRS-4 encodes the insulin receptor substrate 4, a cytoplasmic protein that contains many potential tyrosine and serine/threonine phosphorylation sites. Tyrosine-phosphorylated IRS-4 interacts with cytoplasmic signaling molecules that contain SH2 domains such as IGF1R and FGFR1. IRS-4 is phosphorylated by the insulin receptor tyrosine kinase upon receptor stimulation. IRS-4 is involved in the proliferation and differentiation of hepatoblastoma cell through EPHB2 activation upon IGF1 stimulation.