1b64
SOLUTION STRUCTURE OF THE GUANINE NUCLEOTIDE EXCHANGE FACTOR DOMAIN FROM HUMAN ELONGATION FACTOR-ONE BETA, NMR, 20 STRUCTURES
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OverviewOverview
BACKGROUND: In eukaryotic protein synthesis, the multi-subunit elongation, factor 1 (EF-1) plays an important role in ensuring the fidelity and, regulating the rate of translation. EF-1alpha, which transports the, aminoacyl tRNA to the ribosome, is a member of the G-protein superfamily., EF-1beta regulates the activity of EF-1alpha by catalyzing the exchange of, GDP for GTP and thereby regenerating the active form of EF-1alpha. The, structure of the bacterial analog of EF-1alpha, EF-Tu has been solved in, complex with its GDP exchange factor, EF-Ts. These structures indicate a, mechanism for GDP-GTP exchange in prokaryotes. Although there is good, sequence conservation between EF-1alpha and EF-Tu, there is essentially no, sequence similarity between EF-1beta and EF-Ts. We wished to explore, whether the prokaryotic exchange mechanism could shed any light on the, mechanism of eukaryotic translation elongation. RESULTS: Here, we report, the structure of the guanine-nucleotide exchange factor (GEF) domain of, human EF-1beta (hEF-1beta, residues 135-224); hEF-1beta[135-224], determined by nuclear magnetic resonance spectroscopy. Sequence, conservation analysis of the GEF domains of EF-1 subunits beta and delta, from widely divergent organisms indicates that the most highly conserved, residues are in two loop regions. Intriguingly, hEF-1beta[135-224] shares, structural homology with the GEF domain of EF-Ts despite their different, primary sequences. CONCLUSIONS: On the basis of both the structural, homology between EF-Ts and hEF-1beta[135-224] and the sequence, conservation analysis, we propose that the mechanism of guanine-nucleotide, exchange in protein synthesis has been conserved in prokaryotes and, eukaryotes. In particular, Tyr181 of hEF-1beta[135-224] appears to be, analogous to Phe81 of Escherichia coli EF-Ts.
About this StructureAbout this Structure
1B64 is a Single protein structure of sequence from Homo sapiens. Structure known Active Site: GEF. Full crystallographic information is available from OCA.
ReferenceReference
The solution structure of the guanine nucleotide exchange domain of human elongation factor 1beta reveals a striking resemblance to that of EF-Ts from Escherichia coli., Perez JM, Siegal G, Kriek J, Hard K, Dijk J, Canters GW, Moller W, Structure. 1999 Feb 15;7(2):217-26. PMID:10368288
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