In this link, it states:
It is worth noting that all intracellular RNAs are protected from RNase activity by a number of strategies including 5' end capping, 3' end polyadenylation, and folding within an RNA protein complex (ribonucleoprotein particle or RNP).
I do not understand how polyadenylation protects the intracellular RNA from ribonuclease. I always thought that polyadenylation was a way to mark RNA for degradation, not protect it from degradation. Perhaps it is speaking of protection from exoribonuclease only and not endoribonuclease?
Can someone explain this?