Phylogenetic analysis of plant CNB domains. Un-rooted neighbor-joining tree of CNB domains in Arabidopsis thaliana and Oryza sativa. Shading represents the three classes of CNB domains in plants; shaker-type potassium channels are shown in green, acyl-coA thioesterases are shown in red and CNGC channels are shown in blue. Numbers on the nodes indicate the number of possible trees out of 1000 in which that node was present. Scale represents the number of differences per residue. B) This is an expanded view of the unlabelled region in Figure 3A showing the closely related CNGC proteins more clearly. Tree was generated using ClustalX  and visualized using TreeView . See additional file 4 for sequence alignments.