tailieunhanh - Báo cáo khoa học: Eukaryotic class 1 translation termination factor eRF1 ) the NMR structure and dynamics of the middle domain involved in triggering ribosome-dependent peptidyl-tRNA hydrolysis

The eukaryotic class 1 polypeptide chain release factor is a three-domain protein involved in the termination of translation, the final stage of poly-peptide biosynthesis. In attempts to understand the roles of the mid-dle domain of the eukaryotic class 1 polypeptide chain release factor in the transduction of the termination signal from the small to the large ribo-somal subunit and in peptidyl-tRNA hydrolysis, its high-resolution NMR structure has been obtained. | ỊFEBS Journal Eukaryotic class 1 translation termination factor eRF1 - the NMR structure and dynamics of the middle domain involved in triggering ribosome-dependent peptidyl-tRNA hydrolysis Elena V. Ivanova1 Peter M. Kolosov1 Berry Birdsall2 Geoff Kelly2 Annalisa Pastore2 Lev L. Kisselev1 and Vladimir I. Polshakov3 1 Engelhardt Institute of Molecular Biology Russian Academy of Sciences Moscow Russia 2 Division of Molecular Structure NationalInstitute for MedicalResearch London UK 3 Center for Magnetic Tomography and Spectroscopy M. V. Lomonosov Moscow State University Russia Keywords human class 1 polypeptide chain release factor NMR structure and dynamics termination of protein synthesis Correspondence V. I. Polshakov Center for Magnetic Tomography and Spectroscopy M. V. Lomonosov Moscow State University Moscow 119991 Russia Fax 7 495 2467805 Tel 7 916 1653926 E-mail vpolsha@ Received 15 May 2007 accepted 20 June 2007 doi The eukaryotic class 1 polypeptide chain release factor is a three-domain protein involved in the termination of translation the final stage of polypeptide biosynthesis. In attempts to understand the roles of the middle domain of the eukaryotic class 1 polypeptide chain release factor in the transduction of the termination signal from the small to the large ribosomal subunit and in peptidyl-tRNA hydrolysis its high-resolution NMR structure has been obtained. The overall fold and the structure of the b-strand core of the protein in solution are similar to those found in the crystal. However the orientation of the functionally critical GGQ loop and neighboring a-helices has genuine and noticeable differences in solution and in the crystal. Backbone amide protons of most of the residues in the GGQ loop undergo fast exchange with water. However in the AGQ mutant where functional activity is abolished a significant reduction in the exchange rate of the amide protons has been observed without a noticeable change