title: Overexpression of the phosphatidylinositol synthase gene (ZmPIS) conferring drought stress tolerance by altering membrane lipid composition and increasing ABA synthesis in maize.
abstract: Phosphatidylinositol (PtdIns) synthase is a key enzyme in the phospholipid pathway and catalyses the formation of PtdIns. PtdIns is not only a structural component of cell membranes, but also the precursor of the phospholipid signal molecules that regulate plant response to environment stresses. Here, we obtained transgenic maize constitutively overexpressing or underexpressing PIS from maize (ZmPIS) under the control of a maize ubiquitin promoter. Transgenic plants were confirmed by PCR, Southern blotting analysis and real-time RT-PCR assay. The electrospray ionization tandem mass spectrometry (ESI-MS/MS)-based lipid profiling analysis showed that, under drought stress conditions, the overexpression of ZmPIS in maize resulted in significantly elevated levels of most phospholipids and galactolipids in leaves compared with those in wild type (WT). At the same time, the expression of some genes involved in the phospholipid metabolism pathway and the abscisic acid (ABA) biosynthesis pathway including ZmPLC, ZmPLD, ZmDGK1, ZmDGK3, ZmPIP5K9, ZmABA1, ZmNCED, ZmAAO1, ZmAAO2 and ZmSCA1 was markedly up-regulated in the overexpression lines after drought stress. Consistent with these results, the drought stress tolerance of the ZmPIS sense transgenic plants was enhanced significantly at the pre-flowering stages compared with WT maize plants. These results imply that ZmPIS regulates the plant response to drought stress through altering membrane lipid composition and increasing ABA synthesis in maize.
authors.affiliation: School of Life Science, Shandong University, 27 Shanda South Road, Jinan 250100, China.
authors.forename: Xiuxia
authors.initials: X
authors.lastname: Liu
authors.forename: Shumei
authors.initials: S
authors.lastname: Zhai
authors.forename: Yajie
authors.initials: Y
authors.lastname: Zhao
authors.forename: Baocheng
authors.initials: B
authors.lastname: Sun
authors.forename: Cheng
authors.initials: C
authors.lastname: Liu
authors.forename: Aifang
authors.initials: A
authors.lastname: Yang
authors.forename: Juren
authors.initials: J
authors.lastname: Zhang
mesh_terms: D000040:Abscisic Acid / Q000096:biosynthesis*; D000220:Adaptation, Biological; D051607:CDP-Diacylglycerol-Inositol 3-Phosphatidyltransferase / Q000235:genetics / Q000378:metabolism*; D002462:Cell Membrane / Q000235:genetics / Q000378:metabolism; D018556:Crops, Agricultural / Q000235:genetics / Q000378:metabolism / Q000502:physiology; D055864:Droughts; D035264:Flowers / Q000235:genetics / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D008563:Membrane Lipids / Q000235:genetics / Q000378:metabolism*; D010743:Phospholipids / Q000235:genetics / Q000378:metabolism; D018515:Plant Leaves / Q000201:enzymology / Q000235:genetics / Q000502:physiology; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D030821:Plants, Genetically Modified / Q000235:genetics / Q000378:metabolism / Q000502:physiology; D015398:Signal Transduction; D021241:Spectrometry, Mass, Electrospray Ionization; D013312:Stress, Physiological; D003313:Zea mays / Q000201:enzymology* / Q000235:genetics / Q000502:physiology
chemical_list: D008563:Membrane Lipids; D010743:Phospholipids; D010940:Plant Proteins; D000040:Abscisic Acid; D051607:CDP-Diacylglycerol-Inositol 3-Phosphatidyltransferase