Send to

Choose Destination
Acta Crystallogr D Biol Crystallogr. 2014 Mar;70(Pt 3):658-67. doi: 10.1107/S1399004713032240. Epub 2014 Feb 15.

Conformational transitions in the γ subunit of the archaeal translation initiation factor 2.

Author information

Institute of Protein Research, Russian Academy of Sciences, Pushchino 142290, Moscow Region, Russian Federation.


In eukaryotes and archaea, the heterotrimeric translation initiation factor 2 (e/aIF2) is pivotal for the delivery of methionylated initiator tRNA (Met-tRNA(i)) to the ribosome. It acts as a molecular switch that cycles between inactive (GDP-bound) and active (GTP-bound) states. Recent studies show that eIF2 can also exist in a long-lived eIF2γ-GDP-P(i) (inorganic phosphate) active state. Here, four high-resolution crystal structures of aIF2γ from Sulfolobus solfataricus are reported: aIF2γ-GDPCP (a nonhydrolyzable GTP analogue), aIF2γ-GDP-formate (in which a formate ion possibly mimics P(i)), aIF2γ-GDP and nucleotide-free aIF2γ. The structures describe the different states of aIF2γ and demonstrate the conformational transitions that take place in the aIF2γ `life cycle'.


GTP-binding proteins; Sulfolobus solfataricus; translation initiation factor 2

[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for International Union of Crystallography
Loading ...
Support Center