title: Yas3p, an Opi1 family transcription factor, regulates cytochrome P450 expression in response to n-alkanes in Yarrowia lipolytica.
abstract: In the alkane-assimilating yeast Yarrowia lipolytica, the expression of ALK1, a gene encoding cytochrome P450 that catalyzes the first step of n-alkane oxidation, is induced by n-alkanes. We previously demonstrated that two basic helix-loop-helix proteins, Yas1p and Yas2p, activate the transcription of ALK1 in an alkane-dependent manner by forming a heterocomplex and binding to alkane-responsive element 1 (ARE1), a cis-acting element in the ALK1 promoter. Here we identified an Opi1 family transcription factor, Yas3p, involved in the alkane-dependent transcription regulation of ALK genes. Deletion of YAS3 caused a significant increase in ALK1 mRNA in cells grown on glucose, glycerol, and n-alkanes. The YAS3 deletion also resulted in a marked elevation of reporter gene expression driven by an ARE1-containing promoter on glycerol and n-decane. Bacterially expressed Yas3p bound specifically to Yas2p, but not to Yas1p, in vitro. In addition, although green fluorescent protein-tagged Yas3p was localized in the nucleus in glucose-containing medium, it changed its localization to an endoplasmic reticulum-like compartment upon transfer to medium containing n-decane. These findings suggest that Yas3p functions as a master regulator of transcriptional response, which changes its localization between the nucleus and endoplasmic reticulum membrane in response to different carbon sources. Furthermore, quantitative real time PCR analysis of 12 ALK genes in YAS1, YAS2, and YAS3 deletion mutants suggested that Yas3p is involved in the transcriptional repression of a variety of ALK genes, including ALK1. In contrast, YAS3 deletion did not affect the mRNA level of an INO1 ortholog in Y. lipolytica, indicating functional diversity of Opi1 family transcription factors.
authors.affiliation: Department of Biotechnology, University of Tokyo, Yayoi 1-1-1, Bunkyo-ku, Tokyo 113-8657, Japan.
authors.forename: Kiyoshi
authors.initials: K
authors.lastname: Hirakawa
authors.forename: Satoshi
authors.initials: S
authors.lastname: Kobayashi
authors.forename: Takuro
authors.initials: T
authors.lastname: Inoue
authors.forename: Setsu
authors.initials: S
authors.lastname: Endoh-Yamagami
authors.forename: Ryouichi
authors.initials: R
authors.lastname: Fukuda
authors.forename: Akinori
authors.initials: A
authors.lastname: Ohta
mesh_terms: D021581:Active Transport, Cell Nucleus / Q000187:drug effects / Q000502:physiology; D000473:Alkanes / Q000378:metabolism* / Q000494:pharmacology; D001483:Base Sequence; D002467:Cell Nucleus / Q000201:enzymology / Q000235:genetics; D003577:Cytochrome P-450 Enzyme System / Q000096:biosynthesis* / Q000235:genetics; D003593:Cytoplasm / Q000201:enzymology / Q000235:genetics; D005656:Fungal Proteins / Q000096:biosynthesis* / Q000235:genetics; D017353:Gene Deletion; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects / Q000502:physiology*; D015966:Gene Expression Regulation, Fungal / Q000187:drug effects / Q000502:physiology*; D008969:Molecular Sequence Data; D010084:Oxidation-Reduction; D012331:RNA, Fungal / Q000096:biosynthesis / Q000235:genetics; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*; D025062:Yarrowia / Q000201:enzymology* / Q000235:genetics
chemical_list: D000473:Alkanes; D005656:Fungal Proteins; D012331:RNA, Fungal; D012333:RNA, Messenger; D014157:Transcription Factors; D003577:Cytochrome P-450 Enzyme System; C012867:decane