Question

One function of the poly-A tail on eukaryotic MRNA sequences is to help the MRNA be transported from the nucleus to the cytoplasm. Prokaryotic mRNA also has a poly-A tail. Choose the best explanation of the prokaryotic poly-A tail.

Answer 1

In eukaryotes, it is well known that polyadenylation is required to produce the mature messenger RNA (mRNA) molecule and it provides stability to the mRNA during translation initiation. In prokaryotic organisms, polyadenylation is required for the degradation of the mRNA in a mechanism that involves three steps: endonucleolytic cleavage, polyadenylation and exonucleolytic degradation. Moreover, it is also important to note that no evidence of polyadenylation has bee reported in some prokaryotes including the halophilic bacteria Haloferax volcanic (Slomovic et al. 2005).

Citation:

Slomovic, S., Laufer, D., Geiger, D., & Schuster, G. (2005). Polyadenylation and degradation of human mitochondrial RNA: the prokaryotic past leaves its mark. Molecular and cellular biology, 25(15), 6427-6435.