How to ribosome subunit recognize the m RNA binding site in translation ?

Question

How to ribosome subunit  recognize the m RNA binding site in translation ?

blues · Answer

The ribosome recognises and binds to the Shine Delgarno Sequence in the untranslated part of the mRNA. Site directed mutations in the Shine Delgarno Sequence reduce translation rate by interfering with the binding. For further info, you should read:

Shine J, Dalgarno L (1975). "Determinant of cistron specificity in bacterial ribosomes". Nature 254 (5495): 34–8. doi:10.1038/254034a0. PMID 803646.

anonymous · Answer

Eukaryotic ribosomes recognize the 5' cap on the mRNA via a cap-binding protein

anonymous · Answer

To briefly summarize - as @blues mentioned, the ribosome in prokaryotes binds directly to the Shine-Dalgarno sequence, which is located right before the start codon. This binding prepares and aligns the ribosome for translation. And as @jc7 added, in eukaryotes, the ribosome actually binds first to the 5' cap. Afterwards, it scans downstream until it recognizes and attaches to the Kozak sequence, which comprises the start codon and a few surrounding bases. It's basically the eukaryotic variant of the Shine-Dalgarno sequence.

anonymous · Answer

thanks to all of you :)

anonymous · Answer

The 16S rRNA is component of the 30S small subunit in prokaryotic ribosome.
The 3' end of the 16SrRNA contains the anti-shine dalgarno sequence which binds upatream to the AUG start codon.  The 3'-end of 16S RNA binds to the proteins S1 and S21 known to be involved in initiation of protein synthesis.