Question

In regards to mRNA stability, what is the effect of decapping enzymes?

A) The m7G cap of mRNAs is removed causing mRNAs to be degraded from the 5' end.
B) The splicing of mRNAs is blocked, which destabilizes mRNAs.
C) The m7G cap of mRNAs is stabilized allowing mRNAs to be protected at the 5' end.
D) The polyadenylation of mRNAs is stabilized allowing mRNAs to be protected at the 3' end.
E) The polyadenylation of mRNAs is removed and mRNAs are degraded from the 3' end.

Answer 1

Decapping enzymes remove the protective m7G cap from mRNAs, leading to mRNA degradation from the 5' end and reduced mRNA stability.

Step-by-step explanation:

In regards to mRNA stability, the effect of decapping enzymes is to remove the m7G cap (7-methylguanosine cap) of mRNAs, leading to their degradation from the 5' end. The presence of this cap is crucial for the protection of mRNA from 5' exonucleases, which can degrade unprotected RNAs. Without the m7G cap, the mRNA becomes vulnerable to degradation and this significantly reduces its stability within the cytoplasm, shortening the timeframe during which it can be translated into proteins. Therefore, the correct answer to the question is A) The m7G cap of mRNAs is removed causing mRNAs to be degraded from the 5' end.