Evolutionary relations between the zebrafishKrüppel-like factor (KLF) genes and those from other species.

(A) Amino acid alignment of the C-terminal zinc finger domains of zebrafish KLF proteins with selected vertebrate KLF proteins andDrosophila KRUPPEL. Amino acid identity is marked with black and similarity with gray highlighting. Asterisks mark the invariant zinc-chelating residues, and the arrows indicate those residues that contact the DNA. (B) Phylogenetic tree of the evolutionary relation of zebrafish KLF genes to their close vertebrate relatives andDrosophila Krüppel, based on the sequences of the zinc finger domains of the respective proteins. Numbers give the bootstrap support for given nodes in the phylogram. (C) Amino acid alignment, excluding the zinc finger domain, of the N-termini of zebrafish Klf2a, Klf2b, and Klf4 proteins with their closest vertebrate relatives Klf2 (Lklf) and Klf4 (Gklf). Regions of high similarity are numbered and indicated with brackets; see text for details. (D) Amino acid alignment, excluding the zinc finger domain, of the N-termini of zebrafish Klf12 protein with its close vertebrate relatives Klf3 (Bklf) and Klf12 (AP-2rep). Regions of high similarity are numbered and indicated with brackets; see text for details.