Figure 8. Sequence Identity versus Functional Equivalence, and CCC Evolutionary Hypotheses.
(A) A neighbor-joining tree of the 5 characterized metazoan α-catenin orthologs. Percent identity to Mm 〈E-catenin is indicated in bold. Orthologs sharing > 90% identity are grouped in blue, > 60% in green, and < 60% left uncolored.
(B) A cladogram of the same proteins, as grouped by function. The red oval groups actin-binding monomers, the yellow groups proteins capable of homodimerization, and the purple indicates auto-inhibition of actin binding.
(C) A phylogeny of unikonts, indicating two evolutionary hypotheses of CCC evolution (numbered circles), and two hypotheses for the evolution of dimerization in metazoan 〈-catenins. See text for detailed explanations of hypotheses.