The pH-dependent conformational change of eukaryotic translation initiation factor 5: Insights into partner-binding manner.
Biochem Biophys Res Commun
; 519(1): 186-191, 2019 10 29.
Article
em En
| MEDLINE
| ID: mdl-31492496
ABSTRACT
In the process of eukaryotic translation, the formation of preinitiation complex 43S, which consists of a 40S subunit, the eIF2-GTP-Met-tRNAiMet ternary complex, eIF3, eIF1, eIF1A, and eIF5, is essential for translational quality control. Of those factors, eIF5 promotes the hydrolysis of eIF2-bound GTP to release eIF2-GDP in the complex for the recycling of eIF2. eIF5 appears to bind to the ß subunit of eIF2 (eIF2ß) via an interaction between aromatic/acidic residue-rich regions (AA-boxes) in the C-terminal domain of eIF5 (eIF5CTD) and three lysine clusters (K-boxes) in the N-terminal domain of eIF2ß (eIF2ßNTD). However, the details of this interaction are unclear, due to the lack of a structure for the eIF5-eIF2ß complex, and the unavailability of an intact structure of eIF5, in which the AA-boxes are always disordered, with high flexibility. In this study, we solved two crystal structures of eIF5CTD from Candida albicans, which for the first time showed the AA-box2 of eIF5 presenting as an ordered helical structure. The structures exhibited different arrangements of AA-box2 under different pH values, which may reflect the dynamic nature of the interactions of eIF5CTD, and eIF2ßNTD in the preinitiation complex.
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Base de dados:
MEDLINE
Assunto principal:
Candida albicans
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Fator de Iniciação 5 em Eucariotos
Tipo de estudo:
Prognostic_studies
Idioma:
En
Ano de publicação:
2019
Tipo de documento:
Article