1ryh
From Proteopedia
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| , resolution 1.75Å | |||||||
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| Ligands: | , | ||||||
| Activity: | Small monomeric GTPase, with EC number 3.6.5.2 | ||||||
| Related: | 1RYF
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| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
Alternative Splicing of Rac1 Generates Rac1b, a Self-activating GTPase
Overview
Rac1b was recently identified in malignant colorectal tumors as an alternative splice variant of Rac1 containing a 19-amino acid insertion next to the switch II region. The structures of Rac1b in the GDP- and the GppNHp-bound forms, determined at a resolution of 1.75 A, reveal that the insertion induces an open switch I conformation and a highly mobile switch II. As a consequence, Rac1b has an accelerated GEF-independent GDP/GTP exchange and an impaired GTP hydrolysis, which is restored partially by GTPase-activating proteins. Interestingly, Rac1b is able to bind the GTPase-binding domain of PAK but not full-length PAK in a GTP-dependent manner, suggesting that the insertion does not completely abolish effector interaction. The presented study provides insights into the structural and biochemical mechanism of a self-activating GTPase.
About this Structure
1RYH is a Single protein structure of sequence from Homo sapiens. Full crystallographic information is available from OCA.
Reference
Alternative splicing of Rac1 generates Rac1b, a self-activating GTPase., Fiegen D, Haeusler LC, Blumenstein L, Herbrand U, Dvorsky R, Vetter IR, Ahmadian MR, J Biol Chem. 2004 Feb 6;279(6):4743-9. Epub 2003 Nov 18. PMID:14625275
Page seeded by OCA on Sun Mar 30 23:34:45 2008
