Identification of the Candida albicans Cap1p regulon

Eukaryot Cell. 2009 Jun;8(6):806-20. doi: 10.1128/EC.00002-09. Epub 2009 Apr 24.

Abstract

Cap1p, a transcription factor of the basic region leucine zipper family, regulates the oxidative stress response (OSR) in Candida albicans. Alteration of its C-terminal cysteine-rich domain (CRD) results in Cap1p nuclear retention and transcriptional activation. To better understand the function of Cap1p in C. albicans, we used genome-wide location profiling (chromatin immunoprecipitation-on-chip) to identify its transcriptional targets in vivo. A triple-hemagglutinin (HA(3)) epitope was introduced at the C terminus of wild-type Cap1p (Cap1p-HA(3)) or hyperactive Cap1p with an altered CRD (Cap1p-CSE-HA(3)). Location profiling using whole-genome oligonucleotide tiling microarrays identified 89 targets bound by Cap1p-HA(3) or Cap1p-CSE-HA(3) (the binding ratio was at least twofold; P < or = 0.01). Strikingly, Cap1p binding was detected not only at the promoter region of its target genes but also at their 3' ends and within their open reading frames, suggesting that Cap1p may associate with the transcriptional or chromatin remodeling machinery to exert its activity. Overrepresented functional groups of the Cap1p targets (P < or = 0.02) included 11 genes involved in the OSR (CAP1, GLR1, TRX1, SOD1, CAT1, and others), 13 genes involved in response to drugs (PDR16, MDR1, FLU1, YCF1, FCR1, and others), 4 genes involved in phospholipid transport (PDR16, GIT1, RTA2, and orf19.932), and 3 genes involved in the regulation of nitrogen utilization (GST3, orf19.2693, and orf19.3121), suggesting that Cap1p has other cellular functions in addition to the OSR. Bioinformatic analyses of the bound sequences suggest that Cap1p recognizes the DNA motif 5'-MTKASTMA. Finally, transcriptome analyses showed that increased expression generally accompanies Cap1p binding at its targets, indicating that Cap1p functions as a transcriptional activator.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Basic-Leucine Zipper Transcription Factors
  • Binding Sites
  • Candida albicans / chemistry
  • Candida albicans / genetics*
  • Candida albicans / metabolism*
  • Cell Cycle Proteins / chemistry
  • Cell Cycle Proteins / genetics
  • Cell Cycle Proteins / metabolism*
  • Conserved Sequence
  • Fungal Proteins / chemistry
  • Fungal Proteins / genetics
  • Fungal Proteins / metabolism*
  • Gene Expression Profiling
  • Gene Expression Regulation, Fungal
  • Protein Binding
  • Regulon*
  • Trans-Activators / chemistry
  • Trans-Activators / genetics
  • Trans-Activators / metabolism

Substances

  • Basic-Leucine Zipper Transcription Factors
  • CAP1 protein, Candida albicans
  • Cell Cycle Proteins
  • Fungal Proteins
  • Trans-Activators

Associated data

  • GEO/GSE14258