1qqg
From Proteopedia
| |||||||
| , resolution 2.3Å | |||||||
|---|---|---|---|---|---|---|---|
| Coordinates: | save as pdb, mmCIF, xml | ||||||
CRYSTAL STRUCTURE OF THE PH-PTB TARGETING REGION OF IRS-1
Contents |
Overview
We have determined the crystal structure at 2.3-A resolution of an amino-terminal segment of human insulin receptor substrate 1 that encompasses its pleckstrin homology (PH) and phosphotyrosine binding (PTB) domains. Both domains adopt the canonical seven-stranded beta-sandwich PH domain fold. The domains are closely associated, with a 720-A(2) contact surface buried between them that appears to be stabilized by ionic, hydrophobic, and hydrogen bonding interactions. The nonconserved 46-residue linker between the domains is disordered. The PTB domain peptide binding site is fully exposed on the molecular surface, as is a large cationic patch at the base of the PH domain that is a likely binding site for the head groups of phosphatidylinositol phosphates. Binding assays confirm that phosphatidylinositol phosphates bind the PH domain, but not the PTB domain. Ligand binding to the PH domain does not alter PTB domain interactions, and vice versa. The structural and accompanying functional data illustrate how the two binding domains might act cooperatively to effectively increase local insulin receptor substrate 1 concentration at the membrane and transiently fix the receptor and substrate, to allow multiple phosphorylation reactions to occur during each union.
Disease
Known diseases associated with this structure: Coronary artery disease, susceptibility to OMIM:[147545], Diabetes mellitus, noninsulin-dependent OMIM:[147545]
About this Structure
1QQG is a Single protein structure of sequence from Homo sapiens. Full crystallographic information is available from OCA.
Reference
Crystal structure of the pleckstrin homology-phosphotyrosine binding (PH-PTB) targeting region of insulin receptor substrate 1., Dhe-Paganon S, Ottinger EA, Nolte RT, Eck MJ, Shoelson SE, Proc Natl Acad Sci U S A. 1999 Jul 20;96(15):8378-83. PMID:10411883
Page seeded by OCA on Thu Mar 20 13:41:17 2008
