Question

Briefly explain how 4e-bp proteins control global translation initiation in eukaryote

Answer 1

Initiation

• Initiation of translation occurs at 5’ end of mRNA.

• During initiation mRNA first binds to the small subunit of ribosome in the presence of initiation factors.

• The start codon is AUG it codes for methionine in eukaryotic initiation site and formyl methionine in prokaryotic initiation.

• A tRNA charged with methionine and pair with initiation codon, now the large ribosomal sub unit bind to the small sub unit to complete the initiation complex.

• The large sub unit has two binding sites for tRNA namely the amino acyl tRNA binding site ( A – Site ) and peptidyl site ( P – Site ).

• The initiating tRNA is found at the P - site and all other tRNAs first bind to the A – site and then shift to the P – site.