1u3o
From Proteopedia
Solution structure of rat Kalirin N-terminal SH3 domain
Overview
RhoGEFs are central controllers of small G-proteins in cells and are regulated by several mechanisms. There are at least 22 human RhoGEFs that contain SH3 domains, raising the possibility that, like several other enzymes, SH3 domains control the enzymatic activity of guanine nucleotide exchange factor (GEF) domains through intra- and/or intermolecular interactions. The structure of the N-terminal SH3 domain of Kalirin was solved using NMR spectroscopy, and it folds much like other SH3 domains. However, NMR chemical shift mapping experiments showed that this Kalirin SH3 domain is unique, containing novel cooperative binding site(s) for intramolecular PXXP ligands. Intramolecular Kalirin SH3 domain/ligand interactions, as well as binding of the Kalirin SH3 domain to the adaptor protein Crk, inhibit the GEF activity of Kalirin. This study establishes a novel molecular mechanism whereby intramolecular and intermolecular Kalirin SH3 domain/ligand interactions modulate GEF activity, a regulatory mechanism that is likely used by other RhoGEF family members.
About this Structure
1U3O is a Single protein structure of sequence from Rattus norvegicus. Full crystallographic information is available from OCA.
Reference
Regulation of RhoGEF activity by intramolecular and intermolecular SH3 domain interactions., Schiller MR, Chakrabarti K, King GF, Schiller NI, Eipper BA, Maciejewski MW, J Biol Chem. 2006 Jul 7;281(27):18774-86. Epub 2006 Apr 27. PMID:16644733 Page seeded by OCA on Sat May 3 10:43:20 2008
