Fig. 2.

Human KMT5A functionally substitutes for Set8 during Drosophila development. a) Diagram of Set8, KMT5A, and Set8/KMT5A chimeric proteins expressed from transgenes located on chromosome 3, which also contains the Set8²⁰ null allele. Red shading and nonbold, nonitalic numbers indicate Set8 sequence. Gray shading and bold, italic numbers indicate KMT5A sequence. In parentheses is the total number of amino acids in each protein product. b) Pupation of Set8^WT, KMT5A, and chimera genotypes. Each circle represents the percentage of 40–50 larvae in a vial that reached pupation. The mean and standard deviation of these percentages for 8–10 vials are shown for the indicated genotypes. All transgenic genotypes are in the Set8^20/20 homozygous null background. “2×” indicates that each transgene is also homozygous. Significance was determined by a one-way ANOVA followed by Tukey’s multiple comparison test. P-values for pairwise comparisons can be found in Table 1 and Supplementary Table 3. c) Eclosion into adults of Set8^WT, KMT5A, and chimera genotypes. Here, each circle represents a vial of 40–50 larvae, and 8 vials for each of the indicated genotypes were scored. Genotypes are as in panel B. Significance was determined by a one-way ANOVA followed by Tukey’s multiple comparison test. P-values for pairwise comparisons can be found in Table 1 and Supplementary Table 3. d) Annotated alignment of Set8-related proteins. A total of 301 homologous proteins with over 50% identity to Set8 as identified via BLAST were aligned using Clustal Omega and ordered by phylogeny. Set8 and KMT5A schematics are shown at the top of the diagram with the SET domains indicated by dark blue boxes. Residues of each protein in the alignment that match both Set8 and KMT5A exactly are colored dark red. Those that match only Set8 are colored light blue, and those that match only KMT5A are colored pink. Residues that match neither are colored black. Gaps in the alignment are indicated by white space. e) SEM images of adult eyes of flies of the indicated genotypes. The penetrance of flies displaying a phenotype like that shown is indicated below each image. Both males and females were included in the penetrance calculation. “1×” and “2×” indicate flies containing either 1 or 2 copies, respectively, of the transgene expressing Set8, KMT5A, or Set8/KMT5A chimeras in the Set8^20/20 homozygous null background.