title: Regulation of nitrate and methylamine metabolism by multiple nitrogen sources in the methylotrophic yeast Candida boidinii.
abstract: The methylotrophic yeast Candida boidinii, which is capable of growth on methanol as a sole carbon source, can proliferate on the leaf surface of Arabidopsis thaliana. Previously, we demonstrated that adaptation to a change in the major available nitrogen source from nitrate to methylamine during the host plant aging was crucial for yeast survival on the leaf environment. In this report, we investigated the regulatory profile of nitrate and methylamine metabolism in the presence of multiple nitrogen sources in C. boidinii. The transcript level of nitrate reductase (Ynr1) gene was induced by nitrate and nitrite, and was not repressed by the coexistence with other nitrogen sources. In contrast, the transcript level of amine oxidase (Amo1) gene, which was induced by methylamine, was significantly repressed by the coexistence with ammonium or glutamine. In addition, we investigated the intracellular dynamics of Ynr1 during the nitrogen source shift from nitrate to other compounds. Under these tested conditions, Ynr1 was effectively transported to the vacuole via selective autophagy only during the shift from nitrate to methylamine. Moreover, Ynr1 was subject to degradation after the shift from nitrate to nitrate plus methylamine medium even though nitrate was still available. These regulatory profiles may reflect life style of nitrogen utilization in this yeast living in the phyllosphere.
authors.affiliation: Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kitashirakawa-Oiwake, Sakyo-ku, Kyoto, Japan.
authors.forename: Kosuke
authors.initials: K
authors.lastname: Shiraishi
authors.affiliation: Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kitashirakawa-Oiwake, Sakyo-ku, Kyoto, Japan.
authors.forename: Masahide
authors.initials: M
authors.lastname: Oku
authors.affiliation: Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kitashirakawa-Oiwake, Sakyo-ku, Kyoto, Japan.
authors.forename: Daichi
authors.initials: D
authors.lastname: Uchida
authors.affiliation: Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kitashirakawa-Oiwake, Sakyo-ku, Kyoto, Japan.
authors.forename: Hiroya
authors.initials: H
authors.lastname: Yurimoto
authors.affiliation: Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kitashirakawa-Oiwake, Sakyo-ku, Kyoto, Japan Research Unit for Physiological Chemistry, The Center for the Promotion of Interdisciplinary Education and Research, Kyoto University, Kyoto, Japan Advanced Low Carbon Technology Research and Development Program, Japan Science and Technology Agency, K's Gobancho, 7 Gobancho, Chiyoda-ku, Tokyo, Japan ysakai@kais.kyoto-u.ac.jp.
authors.forename: Yasuyoshi
authors.initials: Y
authors.lastname: Sakai
mesh_terms: D017360:Arabidopsis; D002175:Candida / Q000235:genetics / Q000378:metabolism*; D005656:Fungal Proteins / Q000096:biosynthesis / Q000235:genetics; D020869:Gene Expression Profiling; D015966:Gene Expression Regulation, Fungal; D053858:Metabolic Networks and Pathways / Q000235:genetics*; D008744:Methylamines / Q000378:metabolism*; D009566:Nitrates / Q000378:metabolism*; D009584:Nitrogen / Q000378:metabolism*; D004718:Saccharomycetales; D012926:Social Control, Formal
chemical_list: D005656:Fungal Proteins; D008744:Methylamines; D009566:Nitrates; C027451:methylamine; D009584:Nitrogen
keywords: amine oxidase; autophagy; nitrate reductase; nitrogen metabolism; peroxisome