کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
2030365 | 1071090 | 2006 | 11 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: Two Structurally Atypical HEAT Domains in the C-Terminal Portion of Human eIF4G Support Binding to eIF4A and Mnk1 Two Structurally Atypical HEAT Domains in the C-Terminal Portion of Human eIF4G Support Binding to eIF4A and Mnk1](/preview/png/2030365.png)
SummaryThe X-ray structure of the C-terminal region of human eukaryotic translation initiation factor 4G (eIF4G) has been determined at 2.2 Å resolution, revealing two atypical HEAT-repeat domains. eIF4G recruits various translation factors and the 40S ribosomal subunit to the mRNA 5′ end. In higher eukaryotes, the C terminus of eIF4G (4G/C) supports translational regulation by recruiting eIF4A, an RNA helicase, and Mnk1, the kinase responsible for phosphorylating eIF4E. Structure-guided surface mutagenesis and protein-protein interaction assays were used to identify binding sites for eIF4A and Mnk1 within the HEAT-repeats of 4G/C. p97/DAP5, a translational modulator homologous to eIF4G, lacks an eIF4A binding site in the corresponding region. The second atypical HEAT domain of the 4G/C binds Mnk1 using two conserved aromatic/acidic-box (AA-box) motifs. Within the first AA-box, the aromatic residues contribute to the hydrophobic core of the domain, while the acidic residues form a negatively charged surface feature suitable for electrostatic interactions with basic residues in Mnk1.
Journal: - Volume 14, Issue 5, May 2006, Pages 913–923