title: Morphogenesis-regulated localization of protein kinase A to genomic sites in Candida albicans.
abstract: BACKGROUND
  The human fungal pathogen Candida albicans is able to undergo morphogenesis from a yeast to a hyphal growth form. Protein kinase A (PKA) isoforms Tpk1 and Tpk2 promote hyphal growth in a signalling pathway via the transcription factor Efg1.
  
  
  RESULTS
  C. albicans strains producing epitope-tagged Tpk1 or Tpk2 were used in genome-wide chromatin immunoprecipitation on chip (ChIP chip) to reveal genomic binding sites. During yeast growth, both PKA isoforms were situated primarily within ORFs but moved to promoter regions shortly after hyphal induction. Binding sequences for Tpk2 greatly exceeded Tpk1 sites and did not coincide with binding of the PKA regulatory subunit Bcy1. Consensus binding sequences for Tpk2 within ORFs included ACCAC and CAGCA motifs that appeared to bias codon usage within the binding regions. Promoter residency of Tpk2 correlated with the transcript level of the corresponding gene during hyphal morphogenesis and occurred near Efg1 binding sites, mainly on genes encoding regulators of morphogenesis.
  
  
  CONCLUSIONS
  PKA isoforms change their genomic binding sites from ORF to promoter regions during yeast-hyphal morphogenesis. Tpk2 binds preferentially to promoters of genes encoding regulators of cellular morphogenesis.
authors.forename: Alida
authors.initials: A
authors.lastname: Schaekel
authors.forename: Prashant R
authors.initials: PR
authors.lastname: Desai
authors.affiliation: Department Biologie, Molekulare Mykologie, Heinrich-Heine-Universität, Düsseldorf, Germany. joachim.ernst@uni-duesseldorf.de.
authors.forename: Joachim F
authors.initials: JF
authors.lastname: Ernst
mesh_terms: D001483:Base Sequence; D001665:Binding Sites; D002176:Candida albicans / Q000235:genetics* / Q000378:metabolism*; D017868:Cyclic AMP-Dependent Protein Kinases / Q000737:chemistry / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism; D015870:Gene Expression; D015966:Gene Expression Regulation, Fungal; D056426:Genetic Loci; D023281:Genomics; D025301:Hyphae / Q000235:genetics / Q000378:metabolism; D058977:Molecular Sequence Annotation; D009024:Morphogenesis / Q000235:genetics; D059372:Nucleotide Motifs; D016366:Open Reading Frames; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D021122:Protein Subunits; D021381:Protein Transport; D011993:Recombinant Fusion Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism
chemical_list: D004268:DNA-Binding Proteins; C121438:EFG1 protein, Candida albicans; D005656:Fungal Proteins; D021122:Protein Subunits; D011993:Recombinant Fusion Proteins; D014157:Transcription Factors; D017868:Cyclic AMP-Dependent Protein Kinases