Question

which of the following experimental procedures is most likely to speed up mrna degradation in a eukaryotic cell?

• lengthening of the poly-a tail
• removal of the 5 cap
• removal of c nucleotides
• removal of one or more exons

Explanation:

To determine which procedure speeds up mRNA degradation in eukaryotic cells, we analyze each option:

• Lengthening the poly - A tail: The poly - A tail usually stabilizes mRNA, so lengthening it would not speed up degradation.
• Removal of the 5' cap: The 5' cap protects mRNA from degradation. Removing it makes the mRNA more vulnerable to exonucleases, thus speeding up degradation.
• Removal of C nucleotides: mRNA degradation is not primarily driven by the removal of C nucleotides, as mRNA structure and stability are more related to the 5' cap and poly - A tail.
• Removal of one or more exons: Exons are related to the coding sequence of the mRNA, and their removal does not directly affect mRNA degradation rate.

Answer:

B. removal of the 5' cap