mRNA degradation predominantly proceeds through two alternative routes: the 5′→ 3′
pathway, which requires deadenylation followed by decapping and 5′→ 3′ hydrolysis;
and the 3′→ 5′ pathway, which involves deadenylation followed by 3′→ 5′ hydrolysis
and finally decapping. The mechanisms and relative contributions of each pathway are not
fully understood. We investigated the effects of different cap structure (Gp 3 G, m 7 Gp 3 G, or
m 2 7, 3′-O Gp 3 G) and 3′ termini (A 31, A 60, or G 16) on both translation and mRNA …