Regulation of Cell-Surface Genes and Biofilm Formation by the C. Albicans Transcription Factor Bcr1p

Curr Biol. 2005 Jun 21;15(12):1150-5. doi: 10.1016/j.cub.2005.05.047.

Abstract

The impact of many microorganisms on their environment depends upon their ability to form surface bound communities called biofilms [1]. Biofilm formation on implanted medical devices has severe consequences for human health by providing both a portal of entry and a sanctuary for invasive bacterial and fungal pathogens [1 and 2]. Biofilm regulators and adherence molecules are extensively defined for many bacterial pathogens [3, 4, and 5], but not for fungal pathogens such as Candida albicans. Elongated filaments called hyphae are a prominent feature of C. albicans biofilms, and known genes that promote biofilm formation are required for hyphal development [2, 6, 7 and 8]. From a new library of transcription-factor mutants, we identify Bcr1p, a zinc finger protein required for formation of biofilms but not hyphae. Expression analysis shows that Bcr1p activates cell-surface protein and adhesin genes, including several induced during hyphal development. BCR1 expression depends upon the hyphal regulator Tec1p. Thus, BCR1 is a downstream component of the hyphal regulatory network that couples expression of cell-surface genes to hyphal differentiation. Our results indicate that hyphal cells are specialized to present adherence molecules that support biofilm integrity.

Publication types

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

MeSH terms

  • Biofilms / growth & development*
  • Candida albicans / genetics
  • Candida albicans / physiology*
  • Cell Membrane / genetics*
  • DNA-Binding Proteins / genetics
  • DNA-Binding Proteins / metabolism
  • Fungal Proteins / genetics
  • Fungal Proteins / metabolism
  • Gene Expression Regulation, Fungal*
  • Green Fluorescent Proteins / genetics
  • Green Fluorescent Proteins / metabolism
  • Membrane Glycoproteins / genetics
  • Membrane Glycoproteins / metabolism
  • Mutation
  • Transcription Factors / genetics
  • Transcription Factors / metabolism*
  • Zinc Fingers / genetics

Substances

  • ALS3 protein, Candida albicans
  • DNA-Binding Proteins
  • Fungal Proteins
  • HWP1 protein, Candida albicans
  • Membrane Glycoproteins
  • TEC1 protein, Candida albicans
  • Transcription Factors
  • Green Fluorescent Proteins