Acidic phospholipid-independent interaction of Yas3p, an Opi1-family transcriptional repressor of Yarrowia lipolytica, with the endoplasmic reticulum

Yeast. 2015 Dec;32(12):691-701. doi: 10.1002/yea.3096. Epub 2015 Sep 30.

Abstract

In the n-alkane-assimilating yeast Yarrowia lipolytica, the transcription of ALK1, encoding cytochrome P450, that catalyses n-alkane hydroxylation is activated by a complex composed of Yas1p and Yas2p via a promoter element, ARE1, in response to n-alkanes. An Opi1-family transcription factor, Yas3p, represses the transcription by binding to Yas2p in the nucleus when cultured in glucose-containing medium, but it is localized to the ER, presumably through interaction with acidic phospholipids, phosphatidic acid and/or phospho inositides, when cultured in n-alkane-containing medium. Here, to elucidate the mechanisms regulating the localization of Yas3p, point and deletion mutants of Yas3p were constructed and analysed. The substitution of Trp(360) and Cys(361) by Arg abrogated the localization of Yas3p to the ER and decreased ARE1-mediated transcriptional activation by n-alkane. A Yas3p truncation mutant consisting of residues 259-422 did not bind to acidic phospholipids, but it was localized to the ER in the presence of n-alkane, implying the acidic-phospholipid-independent recruitment of this mutant to the ER in response to n-alkane. The W360R and C361R substitutions in this truncation mutant abolished its localization to the ER. The results suggest that these residues are implicated in the acidic phospholipid-independent interaction of Yas3p to the ER.

Keywords: Yarrowia lipolytica; endoplasmic reticulum; n-alkane; transcription repressor.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alkanes / metabolism
  • Alkanes / pharmacology
  • Cytochrome P-450 Enzyme System / biosynthesis
  • Cytochrome P-450 Enzyme System / genetics
  • Endoplasmic Reticulum / metabolism*
  • Fungal Proteins / genetics
  • Fungal Proteins / metabolism*
  • Gene Deletion
  • Liposomes / metabolism
  • Mutation
  • Phosphatidic Acids / metabolism
  • Phospholipids / metabolism
  • Phospholipids / pharmacology
  • Transcription Factors / genetics
  • Transcription Factors / metabolism
  • Transcription, Genetic
  • Transcriptional Activation
  • Yarrowia / enzymology
  • Yarrowia / genetics*
  • Yarrowia / metabolism*
  • beta-Galactosidase / metabolism

Substances

  • Alkanes
  • Fungal Proteins
  • Liposomes
  • Phosphatidic Acids
  • Phospholipids
  • Transcription Factors
  • Cytochrome P-450 Enzyme System
  • beta-Galactosidase