Fig. 1: The Cyanidioschyzon merolae Aurora kinase CmAUR has conserved properties of Aurora kinase orthologs.

a Localization of CmAUR by immunofluorescence analysis. CmAUR was stained with CmAUR antibody. Mitochondria were stained by Ef-Tu antiserum. DNA was stained with DAPI. White arrowheads indicate signals localized to the spindle or spindle pole. Black arrowheads indicate plastid autofluorescence. Arrows indicate plastid DNA. The Pearson correlation coefficient (PCC) in each cell was calculated using areas without plastids. We observed 24 cells and present representative images in this figure. b Autophosphorylation assay of wild-type and mutant CmAUR. ATP-γS was used as a substrate for autophosphorylation, and the phosphorylation was detected by western blotting using thiophosphate ester antibody. c Mitotic inhibition in a dominant-negative mutant of CmAUR. CmAUR^K208R is a kinase-dead mutant; GFP was used as a negative control. Relevant genes were transiently overexpressed in C. merolae and mitotic cells among transfectants were counted. The error bars indicate standard error of the mean. d Immunofluorescence image of histone H3 Ser10 phosphorylation in mitosis. More than 18 cells were observed. e In vitro phosphorylation assay of histone H3 Ser10 with recombinant CmAUR. Glutathione-S-transferase (GST) was used as a negative control. Distilled water was used as a blank sample. f In vitro phosphorylation assay of histone H3 Ser10 treated with hesperadin. The concentration of hesperadin was 10 µm. The concentration of dimethyl sulfoxide in the final solution was 0.1% (v/v). Bars: 1 µm a, 2  μm c.