what do uncharged tRNAs mean?
low amino acid abundance (tRNAs are normally charged in the cell)
in bacteria, uncharged tRNAs compete with charged tRNAs for binding at?
the A site (translation cannot proceed with an uncharged tRNA in the A site)
binding of tRNA in the A site will?
recruit RelA
what does the stringent response do?
it is a stress response to replenish amino acids (invovles RelA, (p)ppGpp synthesis/magic spot which induces the stress response)
what does uncharged tRNA bind to in eukaryotes?
Gcn2
what does eIF2 normally do?
guides the initial Met-tRNAi^(Met) to the P site
how does Gcn2 affect translation?
an uncharged tRNA binds to Gcn2, then a kinase in Gcn2 phosphorylates eIF2, so that phosphorylated eIF2 cannot initiate translation
what is eIF2B?
A GEF (guanine nucleotide exchange factor) that exchanges on eIF2
how do you inhibit translation initiation by phosphorylating eIF2?
phosphorylation of Ser51 of the eIF2 alpha subunit makes for constitutive binding of eIF2 to eIF2B
phosphorylating Serine51 on eIF2 is
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