English: Overview of RNA decay pathways in the different life domains. Within the two main bacterial lineages, represented by the gram-negative Escherichia coli and the gram-positive Bacillus subtilis (top left and top right panels, respectively), the enzymes differ although the pathways share similarity. In both gram-negative and gram-positive lineages, the endoribonucleases can cleave the substrates repetitively, and the products are attacked by exoribonucleases. The degradation pathways in eukaryotes are shown for comparison.