对比 TGFBR1 Protein, Mouse, Recombinant (hFc)ALK-5,ALK-5ALK5,TGFβRI,tβR-I,LDS1A,TGFbetaRI,TGFB1R1,activin A receptor type II-like kinase, 53kD,TGF-β receptor type I,LDS2A,TGF-bRI,ACVRLK4,TGFR-1,SKR4,TGFBR1,TGF-beta receptor type I,AAT5,tbetaR-ITMPJ-01178
TGF-beta RI, also called ALK-5, is an approximately 55 kDa type I transmembrane serine threonine receptor kinase. In the presence of TGF-beta, TGF-beta RI forms a complex with, and is phosphorylated by, TGF-beta RII. Phosphorylated TGF-beta RI can then transiently bind and phosphorylate Smad2 and Smad3. TGF-beta functions as a tumor suppressor by inhibiting the cell cycle in the G1 phase. Administration of TGF-beta is able to protect against mammary tumor development in transgenic mouse models in vivo. Disruption of the TGF-beta SMAD pathway has been implicated in a variety of human cancers, with the majority of colon and gastric cancers being caused by an inactivating mutation of TGF-beta RII. TGF-beta RI is likely important during development, since mice deficient for TGF-beta RI die at midgestation with severe defects in vascular development of the yolk sac and placenta, and an absence of circulating red blood cells. Furthermore, TGF-beta RI appears to be involved in proper lymphatic network development.