SKN1, a Novel Plant Defensin-Sensitivity Gene in Saccharomyces Cerevisiae, Is Implicated in Sphingolipid Biosynthesis

FEBS Lett. 2005 Mar 28;579(9):1973-7. doi: 10.1016/j.febslet.2005.02.043.


The antifungal plant defensin DmAMP1 interacts with the fungal sphingolipid mannosyl diinositolphosphoryl ceramide (M(IP)(2)C) and induces fungal growth inhibition. We have identified SKN1, besides the M(IP)(2)C-biosynthesis gene IPT1, as a novel DmAMP1-sensitivity gene in Saccharomyces cerevisiae. SKN1 was previously shown to be a KRE6 homologue, which is involved in beta-1,6-glucan biosynthesis. We demonstrate that a Deltaskn1 mutant lacks M(IP)(2)C. Interestingly, overexpression of either IPT1 or SKN1 complemented the skn1 mutation, conferred sensitivity to DmAMP1, and resulted in M(IP)(2)C levels comparable to the wild type. These results show that SKN1, together with IPT1, is involved in sphingolipid biosynthesis in S. cerevisiae.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antifungal Agents / pharmacology*
  • Defensins / pharmacology*
  • Drug Resistance, Fungal / genetics
  • Gene Expression Regulation, Fungal
  • Genes, Plant
  • Genetic Complementation Test
  • Glycosphingolipids / biosynthesis*
  • Glycosphingolipids / genetics
  • Membrane Proteins / genetics
  • Membrane Proteins / physiology*
  • Phosphotransferases (Alcohol Group Acceptor) / genetics
  • Phosphotransferases (Alcohol Group Acceptor) / physiology
  • Plant Proteins / pharmacology*
  • Saccharomyces cerevisiae / drug effects*
  • Saccharomyces cerevisiae / genetics
  • Saccharomyces cerevisiae / metabolism*
  • Saccharomyces cerevisiae Proteins / genetics
  • Saccharomyces cerevisiae Proteins / physiology*
  • Sequence Deletion / genetics


  • Antifungal Agents
  • Defensins
  • Dm-AMP1 protein, Dahlia merckii
  • Glycosphingolipids
  • Membrane Proteins
  • Plant Proteins
  • SKN1 protein, S cerevisiae
  • Saccharomyces cerevisiae Proteins
  • mannose-bis(inositolphospho)ceramide
  • IPT1 protein, S cerevisiae
  • Phosphotransferases (Alcohol Group Acceptor)