Figure 4.

RNA cleavage fragments by RNase H1 or siRNA are degraded by 5’-3’ exonucleases and 3’-5’ exonucleases. In the nucleus, the 5’ cleaved fragments are further degraded from 3’ end by exosomes and Dis3 and from 5’ end by XRN2 after decapping. The 3’ fragment is further degraded by 5’-3’ exonuclease XRN2. In the cytoplasm, the 5’ fragment is degraded by XRN1 from 5’ end after decapping and by cytoplasmic exosome and Dis3L1 from 3’ end. The 3’ fragment is degraded from 5’ end by XRN1. Adapted from ref (152).