title: Transcriptional regulation of the V-ATPase subunit c and V-PPase isoforms in Cucumis sativus under heavy metal stress.
abstract: Two electrogenic proton pumps, vacuolar H(+) transporting ATPase (V-ATPase, EC 3.6.3.14) and vacuolar H(+) transporting inorganic pyrophosphatase (V-PPase, EC 3.6.1.1), co-exist in the vacuolar membrane of plant cells. In this work, all CsVHA and CsVHP genes encoding V-ATPase and V-PPase, respectively, were identified in the cucumber genome. Among them, three CsVHA-c genes for V-ATPase subunit c and two CsVHP1 genes for type I V-PPase were analyzed in detail. Individual isogenes were differentially regulated in plant tissues and during plant development as well as under changing environmental conditions. CsVHA-c1 and CsVHA-c2 showed similar tissue-specific expression patterns with the highest levels in stamens and old leaves. CsVHP1;1 was predominantly expressed in roots and female flowers. In contrast, both CsVHA-c3 and CsVHP1;2 remained in a rather constant ratio in all examined cucumber organs. Under heavy metal stress, the transcript amount of CsVHA-c1 and CsVHP1;1 showed a pronounced stress-dependent increase after copper and nickel treatment. CsVHA-c3 was upregulated by nickel only whereas CsVHA-c2 was induced by all metals with the most visible effect of copper. Additionally, CsVHP1;2 showed a tendency to be upregulated by copper and zinc. We propose that CsVHA-c1, CsVHA-c2 and CsVHP1;1 are essential elements of mechanisms involved in adaptation of cucumber plants to copper toxicity.
authors.affiliation: Department of Plant Molecular Physiology, Institute of Experimental Biology, University of Wrocław, 50-328 , Wrocław, Poland.
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Kabała
authors.forename: Małgorzata
authors.initials: M
authors.lastname: Janicka-Russak
authors.forename: Małgorzata
authors.initials: M
authors.lastname: Reda
authors.forename: Magdalena
authors.initials: M
authors.lastname: Migocka
mesh_terms: D000595:Amino Acid Sequence; D018553:Cucumis sativus / Q000201:enzymology* / Q000235:genetics; D004781:Environmental Exposure; D018506:Gene Expression Regulation, Plant; D043564:Inorganic Pyrophosphatase / Q000737:chemistry* / Q000235:genetics; D019216:Metals, Heavy / Q000737:chemistry* / Q000378:metabolism; D008969:Molecular Sequence Data; D010940:Plant Proteins / Q000737:chemistry / Q000235:genetics; D011522:Protons; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D013312:Stress, Physiological; D014158:Transcription, Genetic; D025262:Vacuolar Proton-Translocating ATPases / Q000737:chemistry* / Q000235:genetics
chemical_list: D019216:Metals, Heavy; D010940:Plant Proteins; D011522:Protons; D025262:Vacuolar Proton-Translocating ATPases; D043564:Inorganic Pyrophosphatase