[GTPases of translational apparatus].
Protein biosynthesis is a complex biochemical process. It integrates multiple steps where different translation factors specifically interact with the ribosome in a precisely defined order. Among the translation factors one can find multiple GTP-binding or G-proteins. Their functioning is accompanied by GTP hydrolysis to the GDP and inorganic phosphate ion Pi. Ribosome stimulates the GTPase activity of the translation factors, thus playing a role analogues to GTPase-activating proteins (GAP). Translation factors--GTPases interact with the ribosome at all stages of protein biosynthesis. Initiation factor 2 (IF2) catalyse initiator tRNA binding to the ribosomal P-site and subsequent subunit joining. Elongation factor Tu (EF-Tu) is responsible for the aminoacyl-tRNA binding to the ribosomal A-site, while elongation factor G (EF-G) catalyses translocation of mRNA in the ribosome by one codon, accompanied by tRNA movement between the binding sites. In its turn, release factor 3 (RF3) catalyse dissociation of the ribosomal complex with release factors 1 or 2 (RF1 or RF2) following the peptide release. This review is devoted to the functional peculiarities of translational GTPases as related to other G-proteins. Particularly, to the putative GTPase activation mechanism, structure and functional cycles.
Kubarenko
A V
AV
Sergiev
P V
PV
Rodnina
M V
MV
D004789:Enzyme Activation; D020963:GTP Phosphohydrolase-Linked Elongation Factors / Q000737:chemistry* / Q000378:metabolism*; D020558:GTP Phosphohydrolases / Q000737:chemistry* / Q000378:metabolism*; D006160:Guanosine Triphosphate / Q000378:metabolism; D014176:Protein Biosynthesis; D012270:Ribosomes / Q000378:metabolism
D006160:Guanosine Triphosphate; D020963:GTP Phosphohydrolase-Linked Elongation Factors; D020558:GTP Phosphohydrolases