Figure 12
From: Structural and evolutionary bioinformatics of the SPOUT superfamily of methyltransferases
A speculative scenario of the evolutionary history of the SPOUT superfamily. This scenario is based on the assumption that Bacteria, Archaea, and Eukaryota are all monophyletic, that Archaea and Eukaryota are sister lineages, and that the root (corresponding to the LUCA) is located in the branch between Bacteria and the Last Common Ancestor of Eukaryota and Archaea (LCAEA). Three major branches corresponding to the three Domains of Life. Lines in different colors indicate COGs (blue: 2'-O-ribose methylation, red: m1G methylation, green: m3U methylation, grey – unknown). Crosses indicate extinction. Dotted arrows indicate putative horizontal gene transfers. Dashed ellipses indicate uncertainty in the assignment of genes that underwent duplication to yield a particular COG, e.g. they encompass sets of potential mother lineages.