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

EMBO J. 1995 Feb 15;14(4):779-90.


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.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acid-Base Equilibrium*
  • Amino Acid Sequence
  • Aspergillus nidulans / genetics*
  • Base Sequence
  • Binding Sites
  • Cloning, Molecular
  • DNA-Binding Proteins / metabolism*
  • Epistasis, Genetic
  • Fungal Proteins / genetics*
  • Gene Expression Regulation, Fungal
  • Molecular Sequence Data
  • Mutagenesis, Site-Directed
  • Promoter Regions, Genetic
  • RNA, Messenger / genetics
  • Sequence Alignment
  • Sequence Homology, Amino Acid
  • Structure-Activity Relationship
  • Transcription Factors / physiology*
  • Zinc Fingers


  • DNA-Binding Proteins
  • Fungal Proteins
  • PacC protein, Aspergillus
  • RNA, Messenger
  • Transcription Factors

Associated data

  • GENBANK/Z47081