Question

Mature eukaryotic mRNA is recognised by

• A. Shine Dalgarno sequence at 5' end.
• B. 7-methyl guanosine at 5'end and polyadenine bases at 3' end.
• C. Anti-shine Dalgarno sequence at 5' end.
• D. Presence of coding and non-coding sequence.

Answer 1

The correct option is B 7-methyl guanosine at 5'end and polyadenine bases at 3' end.

The Shine-Dalgarno (SD) sequence is a ribosomal binding site in prokaryotic mRNA, generally located around 8 bases upstream of the start codon AUG. The RNA sequence helps recruit the ribosome to the mRNA to initiate protein synthesis by aligning the ribosome with the start codon. Mature eukaryotic mRNA is not recognised by Shine-Dalgarno sequence. Coding and non-coding sequences are part of mRNA by which we can not recognise mature mRNA. 7-methyl guanosine at 5'end and polyadenine bases at 3' end are the post transctiptional modifications to mRNA which makes mRNA mature. Thus, option B is correct and other options are wrong.