Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: EC:1.6.5.2 (
NQO1
)
6,196
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
The 4G family of eukaryotic mRNA translation initiation factors is composed of three members (eIF4GI, eIF4GII, and
DAP5
). Their specific roles in translation initiation are under intense investigations, but how their respective intracellular amounts are controlled remains poorly understood. Here we show that eIF4GI and eIF4GII exhibit much shorter half-lives than that of
DAP5
. Both eIF4GI and eIF4GII proteins, but not
DAP5
, contain computer-predicted PEST motifs in their N-termini conserved across the animal kingdom. They are both sensitive to degradation by the proteasome. Under normal conditions, eIF4GI and eIF4GII are protected from proteasomal destruction through binding to the detoxifying enzyme
NQO1
[
NAD(P)H:quinone oxidoreductase
]. However, when cells are exposed to oxidative stress both eIF4GI and eIF4GII, but not
DAP5
, are degraded by the proteasome in an N-terminal-dependent manner, and cell viability is more compromised upon silencing of
DAP5
. These findings indicate that the three eIF4G proteins are differentially regulated by the proteasome and that persistent
DAP5
plays a role in cell survival upon oxidative stress.
...
PMID:Differential Regulation of the Three Eukaryotic mRNA Translation Initiation Factor (eIF) 4Gs by the Proteasome. 3098 42
