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PHR2 of Candida albicans encodes a functional homolog of the pH-regulated gene PHR1 with an inverted pattern of pH-dependent expression.

ABSTRACT: Deletion of PHR1, a pH-regulated gene of Candida albicans, results in pH-conditional defects in growth, morphogenesis, and virulence evident at neutral to alkaline pH but absent at acidic pH. Consequently, we searched for a functional homolog of PHR1 active at low pH. This resulted in the isolation of a second pH-regulated gene, designated PHR2. The expression of PHR2 was inversely related to that of PHR1, being repressed at pH values above 6 and progressively induced at more acidic pH values. The predicted amino acid sequence of the PHR2 protein, Phr2p, was 54% identical to that of Phr1p. A PHR2 null mutant exhibited pH-conditional defects in growth and morphogenesis analogous to those of PHR1 mutants but manifest at acid rather than alkaline pH values. Engineered expression of PHR1 at acid pH in a PHR2 mutant strain and PHR2 at alkaline pH in a PHR1 mutant strain complemented the defects in the opposing mutant. Deletion of both PHR1 and PHR2 resulted in a strain with pH-independent, constitutive growth and morphological defects. These results indicate that PHR1 and PHR2 represent a novel pH-balanced system of functional homologs required for C. albicans to adapt to environments of diverse pH.

SUBMITTER: Muhlschlegel FA

PROVIDER: S-EPMC232444 | biostudies-other | 1997 Oct

REPOSITORIES: biostudies-other

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PHR2 of Candida albicans encodes a functional homolog of the pH-regulated gene PHR1 with an inverted pattern of pH-dependent expression.

Mühlschlegel F A FA Fonzi W A WA

Molecular and cellular biology 19971001 10

Deletion of PHR1, a pH-regulated gene of Candida albicans, results in pH-conditional defects in growth, morphogenesis, and virulence evident at neutral to alkaline pH but absent at acidic pH. Consequently, we searched for a functional homolog of PHR1 active at low pH. This resulted in the isolation of a second pH-regulated gene, designated PHR2. The expression of PHR2 was inversely related to that of PHR1, being repressed at pH values above 6 and progressively induced at more acidic pH values. T ...[more]

PMID: 9315654

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Dataset Information

PHR2 of Candida albicans encodes a functional homolog of the pH-regulated gene PHR1 with an inverted pattern of pH-dependent expression.

Publications

PHR2 of Candida albicans encodes a functional homolog of the pH-regulated gene PHR1 with an inverted pattern of pH-dependent expression.

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