title: VID22 is required for transcriptional activation of the PSD2 gene in the yeast Saccharomyces cerevisiae.
abstract: Phosphatidylethanolamine (PE) in the yeast Saccharomyces cerevisiae is synthesized through decarboxylation of phosphatidylserine (PS), catalysed by PS decarboxylase 1 (Psd1p) and 2 (Psd2p) and the cytidine 5'-diphosphate (CDP)-ethanolamine (CDP-Etn) pathway. PSD1 null (psd1Δ) and PSD2 null (psd2Δ) mutants are viable in a synthetic minimal medium, but a psd1Δ psd2Δ double mutant exhibits Etn auxotrophy, which is incorporated into PE through the CDP-Etn pathway. We have previously shown that psd1Δ is synthetic lethal with deletion of VID22 (vid22Δ) [Kuroda et al. (2011) Mol. Microbiol. 80: , 248-265]. In the present study, we found that vid22Δ mutant exhibits Etn auxotrophy under PSD1-depressed conditions. Deletion of VID22 in wild-type and PSD1-depressed cells caused partial defects in PE formation through decarboxylation of PS. The enzyme activity of PS decarboxylase in an extract of vid22Δ cells was ∼70% of that in wild-type cells and similar to that in psd2Δ cells and the PS decarboxylase activity remaining in the PSD1-depressed cells became almost negligible with deletion of VID22. Thus, the vid22Δ mutation was suggested to cause a defect in the Psd2p activity. Furthermore, vid22Δ cells were shown to be defective in expression of the PSD2 gene tagged with 6×HA, the defect being ameliorated by replacement of the native promoter of the PSD2 gene with a CYC1 promoter. In addition, an α-galactosidase reporter assay revealed that the activity of the promoter of the PSD2 gene in vid22Δ cells was ∼5% of that in wild-type cells. These results showed that VID22 is required for transcriptional activation of the PSD2 gene.
authors.affiliation: Department of Chemistry, Faculty of Sciences, Kyushu University, Hakozaki 6-10-1, Higashi-ku, Fukuoka, Fukuoka 812-8581, Japan.
authors.forename: Non
authors.initials: N
authors.lastname: Miyata
authors.affiliation: Department of Chemistry, Faculty of Sciences, Kyushu University, Hakozaki 6-10-1, Higashi-ku, Fukuoka, Fukuoka 812-8581, Japan.
authors.forename: Takuya
authors.initials: T
authors.lastname: Miyoshi
authors.affiliation: Department of Chemistry, Faculty of Sciences, Kyushu University, Hakozaki 6-10-1, Higashi-ku, Fukuoka, Fukuoka 812-8581, Japan.
authors.forename: Takanori
authors.initials: T
authors.lastname: Yamaguchi
authors.affiliation: Department of Chemistry, Faculty of Sciences, Kyushu University, Hakozaki 6-10-1, Higashi-ku, Fukuoka, Fukuoka 812-8581, Japan.
authors.forename: Toshimitsu
authors.initials: T
authors.lastname: Nakazono
authors.affiliation: Department of Chemistry, Faculty of Sciences, Kyushu University, Hakozaki 6-10-1, Higashi-ku, Fukuoka, Fukuoka 812-8581, Japan.
authors.forename: Motohiro
authors.initials: M
authors.lastname: Tani
authors.affiliation: Department of Chemistry, Faculty of Sciences, Kyushu University, Hakozaki 6-10-1, Higashi-ku, Fukuoka, Fukuoka 812-8581, Japan kuge@chem.kyushu-univ.jp.
authors.forename: Osamu
authors.initials: O
authors.lastname: Kuge
mesh_terms: D002262:Carboxy-Lyases / Q000096:biosynthesis* / Q000235:genetics; D017353:Gene Deletion; D015971:Gene Expression Regulation, Enzymologic / Q000502:physiology*; D015966:Gene Expression Regulation, Fungal / Q000502:physiology*; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism*; D015533:Transcriptional Activation / Q000502:physiology*
chemical_list: D008565:Membrane Proteins; D029701:Saccharomyces cerevisiae Proteins; C469825:VID22 protein, S cerevisiae; D002262:Carboxy-Lyases
keywords: membrane biogenesis; phosphatidylethanolamine; phosphatidylserine decarboxylase; phospholipid metabolism; yeast genetics