Canavanine resistance mutation  can1-1  in  Schizosaccharomyces pombe  is a missense mutation in the ubiquitin ligase adaptor gene  any1 .
In  Schizosaccharomyces pombe , the  can1-1  mutation confers resistance to the toxic arginine analog canavanine. This mutation has been assumed to disrupt a gene encoding an arginine transporter. In PomBase, the gene  SPBC18H10.16  is currently designated  can1 . Here, we sequenced the genomes of three  can1-1  strains. No mutations were found in  SPBC18H10.16 . Instead, these strains harbor an R175C mutation in the gene  any1  ( SPBC18H10.20c ).  any1  encodes an α-arrestin that acts as a ubiquitin ligase adaptor to downregulate plasma membrane amino acid transporters. Our findings indicate that  can1-1  is not a loss-of-function mutation in an amino acid transporter gene, but a possible gain-of-function mutation in a gene encoding a negative regulator of amino acid transporters.
Yang YS, Ning SK, Lyu XH, Suo F, Jia GS, Li W, Du LL