Protein-synthesizing GTPases

Translational GTPases (EC 3.6.5.3) facilitate and control the process of protein synthesis from RNA, through translation. This protein family contains initiation factors and elongation factors, which are found in both prokaryotes and eukaryotes.

Initiation factors (IFs) are involved in the first phase of translation; in prokaryotes these are named PIF1-3, while in eukaryotes there are at least 12 IFs and each is composed of multiple polypeptides. Eukaryotic IFs (eIFs) each have a slightly different role within translation, including start codon recognition, assembly of required complexes and association of the small and large ribosomal subunits. eIFs all bind to the small 40S ribosomal subunit, except for eIF6, which binds to the large 60S ribosomal subunit. Modulation and control of eIF function occurs through their interaction with signaling proteins, particularly those of the PI 3-kinase and MAPK pathways.

Elongation factors (EFs) in prokaryotes and eukaryotes are very similar. In prokaryotes three EFs exist (EF-Tu, EF-Ts and EF-G), while in eukaryotes there are two EFs that control elongation, eEF-1 and eEF-2. eEF-1 is composed of two subunits; the α-subunit mediates entry of transfer RNA to the free site of a ribosome, while the β-subunit acts as a guanine nucleotide exchange factor and catalyzes the release of GDP from the ?-subunit. At the end of each round of protein elongation, eEF-2 catalyzes the translocation of tRNA and mRNA down the ribosome.

External sources of pharmacological information for Protein-synthesizing GTPases :

• BJP Guide

Protein Synthesizing GTPases Gene Data