Fig. 4From: Defining novel plant polyamine oxidase subfamilies through molecular modeling and sequence analysisEvolution of plant PAO subfamilies. Grey thick branches correspond to the green plants species tree as recovered by Gitzendanner an collaborators [61]. The black and grey thin branches denotes the gene trees for each plant PAO subfamily. Gene extinction is denoted by an X, whereas? indicates uncertainty in the actual absence of the subfamilies in Gymnosperms. (a) Subfamily PAObc1. (b) Subfamily PAOtc and PAObc3. (c) Subfamily PAObc2Back to article page