Phylogenetic tree and domain composition of HAC and HAF proteins. Bayesian phylogenetic tree of HAC (A) and HAF (B) predicted proteins from Arabidopsis thaliana (At), Oryza sativa (Os), Solanum lycopersicon (Sl) and Zea mays (Zm). Bootstrap values higher than 50% are shown. The tree is drawn to scale, with branch lengths measured in the number of substitutions per site. (A) KAT11 (PF08214), PHD-finger (PF00628) and zf-TAZ (PF02135) are conserved domains of HAC proteins. (B) N-terminal kinase (PF09247) (TBPb), ubiquitin (PF00240), zinc-finger C2HC (PF01530), and C-terminal bromo BrD (PF00439) are conserved domains of HAFs. A domain of unknown function DUF3591 is also shown.