Fig. 1. Phylogenetic relationship between DdNek2 and other NIMA-related kinases. (A) Pairwise alignment of the DdNek2 and human Nek2 amino-acid sequences using the ClustalW program. Conserved residues specific for NIMA-related kinases are highlighted by the black boxes and residues common to all serine/threonine kinases appear in light gray boxes. The lysine residue that was replaced by arginine in the catalytically inactive kinases is printed in bold and boxed in gray. The six heptads of the leucine zipper are underlined and the end of the catalytic domain is marked by a slash. (B) Phylogenetic trees derived from multiple alignments of all relevant NIMA-related kinases using the complete DdNek2 coding sequence. The alignments were made with the ClustalW program and the trees calculated with the PHYLIP package, version 3.5c. Numbers in brackets refer to the percentage of amino-acid identity to DdNek2. Abbreviations and accession numbers are: Dictyostelium discoideum DdNek2 (SLD805), Xenopus laevis Xl-Nek2A (Q9W622), Mus musculus Mm-Nek2 (O35942), Homo sapiens Hs-Nek2 (P51955), Drosophila melanogaster Dm-Nek2 (Q9W3N8), Schizosaccharomyces pombe Sp-Nrk (O13839), Saccharomyces cerevisiae Sc-KIN3 (P22209), Neurospora crassa Nc-NIM1 (P48479), Aspergillus nidulans An-NIMA (P11837), Tetrahymena pyriformis TpNrk (O76134) and Trypanosoma brucei Tb-Nrk (Q08942).