1nrj
From Proteopedia
OCA (Talk | contribs)
(New page: 200px<br /><applet load="1nrj" size="450" color="white" frame="true" align="right" spinBox="true" caption="1nrj, resolution 1.70Å" /> '''Signal Recognition P...)
Next diff →
Revision as of 20:23, 20 November 2007
|
Signal Recognition Particle Receptor Beta-Subunit in Complex with the SRX Domain from the Alpha-Subunit
Overview
Protein translocation across and insertion into membranes is a process, essential to all life forms. In higher eukaryotes, this process is, initiated by targeting the translating ribosome to the endoplasmic, reticulum via the signal recognition particle (SRP) and its, membrane-associated heterodimeric receptor (SR). This targeting step is, regulated by three G proteins, SRP54, SR alpha, and SR beta, which act in, concert. Little is known about the regulatory role of SR beta. Here, we, present the 1.7 A crystal structure of the SR beta-GTP subunit in complex, with the interaction domain of SR alpha. Strikingly, the binding interface, overlaps largely with the switch 1 region of SR beta. This finding, together with additional biochemical data, shows that the eukaryotic SR is, a conditional and not an obligate heterodimer. The results suggest that, the GTP/GDP switch cycle of SR beta functions as a regulatory switch for, the receptor dimerization. We discuss the implications for the, translocation pathway.
About this Structure
1NRJ is a Protein complex structure of sequences from Saccharomyces cerevisiae with MG, GTP and EDO as ligands. Full crystallographic information is available from OCA.
Reference
Structural basis for the function of the beta subunit of the eukaryotic signal recognition particle receptor., Schwartz T, Blobel G, Cell. 2003 Mar 21;112(6):793-803. PMID:12654246
Page seeded by OCA on Tue Nov 20 22:30:28 2007
