Cytoplasmic localization of the white phase-specific WH11 gene product of Candida albicans.

Cells of Candida albicans WO-1 switch frequently, spontaneously and reversibly between a white and opaque phase. The white-opaque transition involves the regulation of phase-specific genes. In the white budding phase, cells express the white phase-specific gene WH11, which encodes a protein with homology to the heat shock protein Hsp12 of Saccharomyces cerevisiae. A recombinant Wh11 protein has been synthesized, purified to apparent homogeneity and used to generate a rabbit polyclonal antiserum. The antiserum was used to localize the Wh11 protein in white phase cells. Wh11 is distributed throughout the cytoplasm but appears to be excluded from vesicles, plasma membrane and nucleus. An analysis by Western blotting of Wh11 expression in a number of C. albicans strains and related species suggests a correlation between round budding cell shape and expression.