High impact information on SUI3

• A yeast protein, Sui3, isolated as an extragenic suppressor of his4 initiation codon mutations, exhibits extensive sequence identity with human eIF-2 beta, especially in the polylysine and zinc finger domains, thereby reinforcing the view that these elements are important for function [1].
• Mutations at a Zn(II) finger motif in the yeast eIF-2 beta gene alter ribosomal start-site selection during the scanning process [2].
• Biochemical characterization of SUI3 suppressor alleles that encode mutant forms of the beta subunit of eIF-2 revealed that these mutant eIF-2 complexes have a higher intrinsic rate of GTP hydrolysis, which is eIF-5 independent [3].
• The latter result indicates that the gamma subunit of eIF-2 participates in recognition of the start site for protein synthesis, a role previously demonstrated in yeast for eIF-2 alpha and eIF-2 beta [4].
• We have characterized a new ankyrin (ANK) repeat-containing Saccharomyces cerevisiae gene, YAR1, located between the HSP82 and SUI3 genes on chromosome XVI [5].

Other interactions of SUI3

• The SUI2 and SUI3 genes of Saccharomyces cerevisiae encode the alpha and beta subunits, respectively, of translation initiation factor eIF-2 (eukaryotic initiation factor 2) [6].
• The effect of the hem12 mutation is also partially reversed by the known SUI3 suppressor encoding the beta subunit of eIF2 [7].

References