1khu
From Proteopedia
Smad1 crystal structure reveals the details of BMP signaling pathway
Overview
Phosphorylation of Smad1 at the conserved carboxyl terminal SVS sequence activates BMP signaling. Here we report the crystal structure of the Smad1 MH2 domain in a conformation that reveals the structural effects of phosphorylation and a molecular mechanism for activation. Within a trimeric subunit assembly, the SVS sequence docks near two putative phosphoserine binding pockets of the neighboring molecule, in a position ready to interact upon phosphorylation. The MH2 domain undergoes concerted conformational changes upon activation, which signal Smad1 dissociation from the receptor kinase for subsequent heteromeric assembly with Smad4. Biochemical and modeling studies reveal unique favorable interactions within the Smad1/Smad4 heteromeric interface, providing a structural basis for their association in signaling.
About this Structure
1KHU is a Single protein structure of sequence from Homo sapiens. Full crystallographic information is available from OCA.
Reference
Structural basis of Smad1 activation by receptor kinase phosphorylation., Qin BY, Chacko BM, Lam SS, de Caestecker MP, Correia JJ, Lin K, Mol Cell. 2001 Dec;8(6):1303-12. PMID:11779505 Page seeded by OCA on Fri May 2 22:45:58 2008
