The Research To The Mechanism Of TGF-β Activate ERK Pathway

The transforming growth factor beta (TGF-β) is a multifunctional peptide growth factor that is involved in diverse biological pro- cesses,including growth, proliferation,differentiation, and apoptosis.TGF-βactivated many cellular signaling pathways.TGF-β/Smad pathway was initiated by their association with a type-Ⅱreceptor serine-threonine kinase,which then recruits and transphosphorylates a type-receptor,also a transmembrane serine-threonine kinase.Trans- phosphorylation of the typeⅠreceptor by the typeⅡreceptor takes place on several residues in a glycine-serine-rich juxtamembrane domain and leads to activation of the receptor. This activated typeⅠreceptor phosphorylates two C-terminal serine residues of Smad 2 or Smad3, inducing complex formation with Smad4 and then translocation into the nucleus.There the complexes interact with other transcription factors to induce or repress transcription of a number of target genes.Together with the recent findings that in addition to Smad pathway,TGF-βalso can activate mitogen-activated protein kinase (MAPK) pathway,But the mechanism of TGF-βactivated MAPK is not clarified.In...