Protein phosphorylation plays an important role in the control of translation by eukaryotic initiation factor-2 (eIF-2). eIF-2 binds GTP and Met-tRNAi and transfers the Met-tRNA to the 40S subunit, to form the 43S preinitiation complex. Later in the cycle, prior to elongation, the bound GTP is hydrolyzed , releasing eIF-2-GDP. For eIF-2 to promote another round of initiation, GDP must be exchanged for GTP, a reaction catalyzed by eIF-2B. Kinases activated by viral infection (PKR), endoplasmic reticulum stress (PERK/PEK), amino acid deprivation (GCN2), and hemin deficiency (HRI) can phosphorylate the a subunit of eIF-2. This phosphorylation stabilizes the eIF-2-GDP-eIF-2B complex, inhibiting the turnover of eIF-2B. eIF-2B is also inhibited by GSK-3b phosphorylation. These events result in a shut-down of cellular protein synthesis and can lead to apoptosis.
7.0: Changed members. Upgraded to final version of Biocarta.
License Terms for BioCarta data in MSigDB
MSigDB gene sets derived from BioCarta pathways are protected by copyright, (c) 2000-2017 BioCarta, all rights reserved. They are provided
under license to the Broad Institute, Inc. with qualified permission to include in this release, subject to Biocarta's
"Disclaimer
of Liability and of Warranties" (formerly found at www.biocarta.com). Inclusion of these gene
sets is conditioned upon acknowledgment and retention of the aforementioned copyright, and agreement to such disclaimer. The BioCarta
derived gene sets are in the MSigDB C2 and M2 collections, and can be recognized by the "BIOCARTA_" prefix in their name.
