Mutational analyses of human eIF5A-1--identification of amino acid residues critical for eIF5A activity and hypusine modification.

ABSTRACT: The eukaryotic translation initiation factor 5A (eIF5A) is the only protein that contains hypusine [Nepsilon-(4-amino-2-hydroxybutyl)lysine], which is required for its activity. Hypusine is formed by post-translational modification of one specific lysine (Lys50 for human eIF5A) by deoxyhypusine synthase and deoxyhypusine hydroxylase. To investigate the features of eIF5A required for its activity, we generated 49 mutations in human eIF5A-1, with a single amino acid substitution at the highly conserved residues or with N-terminal or C-terminal truncations, and tested mutant proteins in complementing the growth of a Saccharomyces cerevisiae eIF5A null strain. Growth-supporting activity was abolished in only a few mutant eIF5As (K47D, G49A, K50A, K50D, K50I, K50R, G52A and K55A), with substitu

SUBMITTER: Cano VS 

PROVIDER: S-EPMC2536608 | biostudies-literature | 2008 Jan

REPOSITORIES: biostudies-literature