2pjy
From Proteopedia
Structural basis for cooperative assembly of the TGF-beta signaling complex
Structural highlights
DiseaseTGFB3_HUMAN Defects in TGFB3 are a cause of familial arrhythmogenic right ventricular dysplasia type 1 (ARVD1) [MIM:107970; also known as arrhythmogenic right ventricular cardiomyopathy 1 (ARVC1). ARVD is an autosomal dominant disease characterized by partial degeneration of the myocardium of the right ventricle, electrical instability, and sudden death. It is clinically defined by electrocardiographic and angiographic criteria; pathologic findings, replacement of ventricular myocardium with fatty and fibrous elements, preferentially involve the right ventricular free wall.[1] FunctionTGFB3_HUMAN Involved in embryogenesis and cell differentiation. Evolutionary ConservationCheck, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedDimeric ligands of the transforming growth factor-beta (TGF-beta) superfamily signal across cell membranes in a distinctive manner by assembling heterotetrameric complexes of structurally related serine/threonine-kinase receptor pairs. Unlike complexes of the bone morphogenetic protein (BMP) branch that apparently form due to avidity from membrane localization, TGF-beta complexes assemble cooperatively through recruitment of the low-affinity (type I) receptor by the ligand-bound high-affinity (type II) pair. Here we report the crystal structure of TGF-beta3 in complex with the extracellular domains of both pairs of receptors, revealing that the type I docks and becomes tethered via unique extensions at a composite ligand-type II interface. Disrupting the receptor-receptor interactions conferred by these extensions abolishes assembly of the signaling complex and signal transduction (Smad activation). Although structurally similar, BMP and TGF-beta receptors bind in dramatically different modes, mediating graded and switch-like assembly mechanisms that may have coevolved with branch-specific groups of cytoplasmic effectors. Cooperative assembly of TGF-beta superfamily signaling complexes is mediated by two disparate mechanisms and distinct modes of receptor binding.,Groppe J, Hinck CS, Samavarchi-Tehrani P, Zubieta C, Schuermann JP, Taylor AB, Schwarz PM, Wrana JL, Hinck AP Mol Cell. 2008 Feb 1;29(2):157-68. PMID:18243111[2] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
|