THE STL1 GENE OF SACCHAROMYCES-CEREVISIAE IS PREDICTED TO ENCODE A SUGAR TRANSPORTER-LIKE PROTEIN

A gene has been cloned from the yeast Saccharomyces cerevisiae which, on the basis of the deduced translation product, encodes a sugar trans porter-like protein. This gene, STL1, was identified as an open readin g frame (ORF) closely linked to the cinnamic-acid-resistance gene POF1 on chromosome IV. The putative translation product of STL1 (STL1) con tains 536 amino acids, with a M(r) of 60 507. Hydropathy analysis of S TL1 suggests that it contains the twelve transmembrane (TM) domains ch aracteristic of a family of sugar transporters from S. cerevisiae and other organisms. STL1 displays greatest homology (28% identity) to the products of the yeast HXT2 (hexose transporter) and GAL2 (galactose t ransporter) genes. Disruption of STL1 had no detectable effect on yeas t growth on glucose, galactose, mannose, maltose or glycerol as sole c arbon source. The transport function of the gene product remains unkno wn at present.