PDR3, a new yeast regulatory gene, is homologous to PDR1 and controls the multidrug resistance phenomenon.

摘要: TheSaccharomyces cerevisiae PDR3 gene, located near the centromere of chromosome II, has been completely sequenced and characterised. Mutationspdr3-1 andpdr3-2, which confer resistance to several antibiotics can be complemented by a wild-type allele gene. The sequence wild-typePDR3 gene revealed presence long open reading frame capable encoding 976-amino acid protein. protein contains single Zn(II)2Cys6 binuclear-type zinc finger homologous DNA-binding motifs other transcriptional activators from lower eukaryotes. Evidence that is activator was provided demonstrating DNA-bound LexA-PDR3 fusion proteins stimulate expression nearby promoter containing LexA binding sites. use fusions two activation domains, one localised N-terminal, cysteine-rich domain at C-terminus. salient feature its similarity coded byPDR1, responsible forpleiotropicdrugresistance. show 36% amino identity over their entire length domains are highly conserved. fact absence both PDR1 (simultaneous disruption genes) enhances multidrug sensitivity strongly suggests factors have closely related functions.