Figure 8From: Evolutionary connection between the catalytic subunits of DNA-dependent RNA polymerases and eukaryotic RNA-dependent RNA polymerases and the origin of RNA polymerasesAn evolutionary scenario for the SBHM domains from the DDRP subunits and other proteins. The scenario for the derivation of various versions of the SHBM fold from the simple, ancestral 3-stranded unit was inferred from phyletic patterns, structural features and the internal duplication. The conserved basic residue present in the biotin/lipoate-binding domain-type SBHMs and the β subunit of the DDRPs is shows as a ball-and-stick model. The emergence of different lineage-specific specializations is indicated to the side of each clade.Back to article page