The Indispensable N-Terminal Half of elF3j/HCR1 Cooperates with its Structurally Conserved Binding Partner eIF3b/PRT1-RRM and with eIF1A in Stringent AUG Selection

0354155 - MBÚ 2011 RIV GB eng J - Journal Article
ElAntak, L. - Wagner, Susan - Herrmannová, Anna - Karásková, Martina - Rutkai, Edit - Lukavsky, P. J. - Valášek, Leoš
The Indispensable N-Terminal Half of elF3j/HCR1 Cooperates with its Structurally Conserved Binding Partner eIF3b/PRT1-RRM and with eIF1A in Stringent AUG Selection.
Journal of Molecular Biology. Roč. 396, č. 4 (2010), s. 1097-1116. ISSN 0022-2836. E-ISSN 1089-8638
Institutional research plan: CEZ:AV0Z50200510
Keywords : translation initiation * AUG recognition * eIF3
Subject RIV: CE - Biochemistry
Impact factor: 4.008, year: 2010

Despite the recent progress in our understanding of the numerous functions of individual subunits of eukaryotic translation initiation factor 3 (eIF3), there is still only little known on the molecular level. Using NMR spectroscopy, we determined the first solution structure of an interaction between eIF3 subunits. We revealed that a conserved tryptophan residue in the human eIF3j N-terminal acidic domain (NTA) is held in the helix α1 – loop L5 hydrophobic pocket of the human eIF3b-RRM. Mutating the corresponding “pocket” residues in its yeast orthologue reduces cellular growth rate, eliminates eIF3j/HCR1 association with eIF3b/PRT1 in vitro and in vivo, affects 40S-occupancy of eIF3, and produces a leaky scanning defect indicative of a deregulation of the AUG selection process. Unexpectedly, we found that the N-terminal half (NTD) of eIF3j/HCR1 containing the NTA motif is indispensable and sufficient for wild-type growth of yeast cells
Permanent Link: http://hdl.handle.net/11104/0193217