CANDIDA-ALBICANS HEX1 GENE, A REPORTER OF GENE-EXPRESSION IN SACCHAROMYCES-CEREVISIAE

The Candida albicans HEX1 gene was examined as a reporter of gene expr ession in Saccharomyces cerevisiae. The galactose-inducible S. cerevis iae GAL1-GAL10 promoter was inserted upstream of the C. albicans HEX1 gene, which encodes N-acetylglucosaminidase. The gene was introduced i nto S. cerevisiae AH22, which has no background N-acetylglucosaminidas e activity. Expression of HEX1 in transformed cells was induced signif icantly by galactose and was repressed by glucose. The HEX1 gene produ ct was functional in S, cerevisiae cells and was targeted to the perip lasm. Both untransformed S. cerevisiae cells and cells expressing HEX1 had similar growth curves and cell morphology indicating that express ion of N-acetylglucosaminidase was not toxic to the host strain. These results demonstrate that the HEX1 gene can be a useful reporter of ge ne expression in S. cerevisiae.