Figure 5.

(A) Evolutionary origins and trajectories of release factors and ribosome rescue pathways, with factors listed at points of emergence/transfer. Transfer events are depicted with arrows and labeled; when timing is unclear the lines are broken. The mitochondrial endosymbiotic event is represented by a large green circle. Complexes formed by release/rescue factors are depicted to the right. Circles are color-coordinated with tree to represent the superkingdom of origin of a component. (B) Relative presence/absence for individual components of the ribosome quality control and rescue pathways. Presence/absence is colored by percentage of genomes within taxa which contain a given component. Names of taxa are colored by superkingdom. Components containing a RF-PH domain are marked to the right of their name by a red circle. Abbreviations: tack, Thaumarchaeota, Crenarchaeota, and Korarchaeota superphylum; dpann, Diapherotrites, Parvarchaeota, Aenigmarchaeota, Nanoarchaeota, and Nanohaloarchaea superphylum; PVC group, Chlamydiae, Lentisphaerae, Planctomycetes, and Verrucomicrobia bacterial superphylum; FCB, Fibrobacteres, Bacteroidetes, and Chlorobi superphylum; CPR, Candidate Phyla Radiation.