Candida albicans Mds3p, a conserved regulator of pH responses and virulence identified through insertional mutagenesis.
Candida albicans is a commensal fungus that causes diverse infections after antibiotic use or immune debilitation. Gene discovery has been limited because the organism is an asexual diploid. We have developed a strategy that yields random homozygous insertion mutants. The strategy has permitted identification of several prospective essential genes. Many of these genes are homologous to nonessential Saccharomyces cerevisiae genes, and some have no S. cerevisiae homolog. These findings may expand the range of antifungal drug targets. We have also identified new genes required for pH-dependent filamentation, a trait previously associated with virulence. One newly identified gene, MDS3, is required for expression in alkaline media of two filamentation-associated genes, HWP1 and ECE1, but is not required for expression of other pH-response genes. In S. cerevisiae, the two MDS3 homologs are required for growth in alkaline media, thus arguing that Mds3p function in adaptation to external pH changes is conserved. Epistasis tests show that Mds3p contributes to virulence and alkaline pH responses independently of the well-characterized Rim101p pH-response pathway.
Davis
Dana A
DA
Department of Microbiology and Integrated Program in Cellular, Molecular, and Biophysical Studies, Columbia University, New York, New York 10032, USA.
Bruno
Vincent M
VM
Loza
Lucio
L
Filler
Scott G
SG
Mitchell
Aaron P
AP
D000818:Animals; D002176:Candida albicans / Q000235:genetics* / Q000378:metabolism* / Q000472:pathogenicity; D005656:Fungal Proteins / Q000235:genetics* / Q000378:metabolism*; D005800:Genes, Fungal; D006863:Hydrogen-Ion Concentration; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D016254:Mutagenesis, Insertional; D012097:Repressor Proteins / Q000235:genetics* / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism / Q000472:pathogenicity; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics* / Q000378:metabolism*; D013045:Species Specificity; D014774:Virulence / Q000235:genetics
D005656:Fungal Proteins; C110020:MDS3 protein, S cerevisiae; D012097:Repressor Proteins; D029701:Saccharomyces cerevisiae Proteins