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The Aspergillus PacC zinc finger transcription factor mediates regulation of both acid- and alkaline-expressed genes by ambient pH.

ABSTRACT: The pH regulation of gene expression in Aspergillus nidulans is mediated by pacC, whose 678 residue-derived protein contains three putative Cys2His2 zinc fingers. Ten pacCc mutations mimicking growth at alkaline pH remove between 100 and 214 C-terminal residues, including a highly acidic region containing an acidic glutamine repeat. Nine pacC+/- mutations mimicking acidic growth conditions remove between 299 and 505 C-terminal residues. Deletion of the entire pacC coding region mimics acidity but leads additionally to poor growth and conidiation. A PacC fusion protein binds DNA with the core consensus GCCARG. At alkaline ambient pH, PacC activates transcription of alkaline-expressed genes (including pacC itself) and represses transcription of acid-expressed genes. pacCc mutations obviate the need for pH signal transduction.

SUBMITTER: Tilburn J

PROVIDER: S-EPMC398143 | biostudies-other | 1995 Feb

REPOSITORIES: biostudies-other

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The Aspergillus PacC zinc finger transcription factor mediates regulation of both acid- and alkaline-expressed genes by ambient pH.

Tilburn J J Sarkar S S Widdick D A DA Espeso E A EA Orejas M M Mungroo J J Peñalva M A MA Arst H N HN

The EMBO journal 19950201 4

The pH regulation of gene expression in Aspergillus nidulans is mediated by pacC, whose 678 residue-derived protein contains three putative Cys2His2 zinc fingers. Ten pacCc mutations mimicking growth at alkaline pH remove between 100 and 214 C-terminal residues, including a highly acidic region containing an acidic glutamine repeat. Nine pacC+/- mutations mimicking acidic growth conditions remove between 299 and 505 C-terminal residues. Deletion of the entire pacC coding region mimics acidity bu ...[more]

PMID: 7882981

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