Fig 1.

A frameshift mutation in the RIM15 gene specific to modern sake yeast strains. (A) Comparison between laboratory strain S288C Rim15p (ScRim15p) and the putative RIM15 gene product of sake yeast strain K7 (K7Rim15p). Rectangles with light, medium, and dark shading and filled rectangles represent the PAS, CCHC-type zinc finger, receiver (REC), and protein kinase (PK) catalytic domains, respectively. Nucleotide and amino acid sequences surrounding the frameshift mutation in K7 (A1686fs; corresponding to nucleotides A5053 to C5088 in the ScRIM15 gene) are also shown. Filled circles and filled and open triangles indicate the positions of single amino acid substitutions, insertion of four asparagine residues, and the single-base frameshift mutation, respectively. (B) Distribution of the frameshift mutation in the RIM15 gene (rim15^5055insA) and the modern sake yeast-specific loss-of-function mutation in the MSN4 gene (msn4^C1540T) (39) among Saccharomyces cerevisiae and Saccharomyces sensu stricto strains. Nucleotides that differ from the DNA sequence of S. cerevisiae strain S288C (uppermost) are indicated by boldface. The rim15^5055insA and msn4^C1540T mutations are highlighted in gray.