KNR4 is a member of the PKC1 signalling pathway and genetically interacts with BCK2, a gene involved in cell cycle progression in Saccharomyces cerevisiae

Curr Genet. 2002 Aug;41(5):323-32. doi: 10.1007/s00294-002-0299-6. Epub 2002 Jul 23.

Abstract

In budding yeast, PKC1 plays an essential role in cell wall integrity and cell proliferation through a bifurcated PKC1/mitogen-activated protein (MAP) kinase pathway. The evidence that KNR4 is a member of the PKC1 pathway and genetically interacts with BCK2, a gene involved together with Cln3-Cdc28 in the G1 to S transition phase of the cell cycle, was as follows. Both KNR4 and BCK2 were isolated as a dosage suppressor of a calcofluor white hypersensitive ( cwh43) mutant. Overexpression of either of the two genes in a wild-type strain led to increased resistance to wall-affecting drugs, while this effect was not obtained in a bck2 Delta mutant that overexpressed KNR4. Deletion of KNR4 or BCK2 was synthetically lethal with components of the linear PKC1/MAP kinase pathway. Loss of Knr4 was lethal in combination with loss of Cln3, as was shown for Bck2. A protein interaction between Knr4 and Bck2 was measured using the two-hybrid system, although a direct physical interaction could not be detected by co-immunuprecipation methods. Finally, a genome-wide analysis of cells that overexpress BCK2 or KNR4 indicated that both genes also have effects independent of each other. In particular, the microarray data showed up-regulation of SWI4, which may account for the suppression of the cell lysis of a pkc1 null mutant, due to overexpression of BCK2.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cyclin G
  • Cyclins / metabolism
  • Fungal Proteins / metabolism*
  • Intracellular Signaling Peptides and Proteins
  • MAP Kinase Signaling System / genetics*
  • MAP Kinase Signaling System / physiology
  • Oligonucleotide Array Sequence Analysis
  • Phosphoproteins / genetics*
  • Phosphoproteins / metabolism
  • Protein Kinase C / metabolism*
  • Saccharomyces cerevisiae / genetics
  • Saccharomyces cerevisiae / growth & development
  • Saccharomyces cerevisiae / metabolism
  • Saccharomyces cerevisiae Proteins / genetics*
  • Saccharomyces cerevisiae Proteins / metabolism
  • Transcription Factors

Substances

  • BCK2 protein, S cerevisiae
  • Cyclin G
  • Cyclins
  • Fungal Proteins
  • Intracellular Signaling Peptides and Proteins
  • Phosphoproteins
  • SMI1 protein, S cerevisiae
  • Saccharomyces cerevisiae Proteins
  • Transcription Factors
  • Pkc1 protein, Trichoderma reesei
  • Protein Kinase C