title: The Arabidopsis polyamine transporter LHR1/PUT3 modulates heat responsive gene expression by enhancing mRNA stability.
abstract: Polyamines involve in gene regulation by interacting with and modulating the functions of various anionic macromolecules such as DNA, RNA and proteins. In this study, we identified an important function of the polyamine transporter LHR1 (LOWER EXPRESSION OF HEAT RESPONSIVE GENE1) in heat-inducible gene expression in Arabidopsis thaliana. The lhr1 mutant was isolated through a forward genetic screening for altered expression of the luciferase reporter gene driven by the promoter from the heat-inducible gene AtHSP18.2. The lhr1 mutant showed reduced induction of the luciferase gene in response to heat stress and was more sensitive to high temperature than the wild type. Map-based cloning identified that the LHR1 gene encodes the polyamine transporter PUT3 (POLYAMINE UPTAKE TRANSPORTER 3) localized in the plasma membrane. The LHR1/PUT3 is required for the uptake of extracellular polyamines and plays an important role in stabilizing the mRNAs of several crucial heat stress responsive genes under high temperature. Genome-wide gene expression analysis using RNA-seq identified an array of differentially expressed genes, among which the transcript levels of some of the heat shock protein genes significantly reduced in response to prolonged heat stress in the lhr1 mutant. Our findings revealed an important heat stress response and tolerance mechanism involving polyamine influx which modulates mRNA stability of heat-inducible genes under heat stress conditions.
authors.affiliation: Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX, 79409, USA.
authors.forename: Yun
authors.initials: Y
authors.lastname: Shen
authors.affiliation: Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX, 79409, USA.
authors.forename: Qingxia
authors.initials: Q
authors.lastname: Ruan
authors.affiliation: Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX, 79409, USA.
authors.forename: Haoxi
authors.initials: H
authors.lastname: Chai
authors.affiliation: Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan, 430079, China.
authors.forename: Yongze
authors.initials: Y
authors.lastname: Yuan
authors.affiliation: Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan, 430079, China.
authors.forename: Wannian
authors.initials: W
authors.lastname: Yang
authors.affiliation: Plant Stress and Germplasm Development Unit, USDA-ARS, Lubbock, TX, 79415, USA.
authors.forename: Junping
authors.initials: J
authors.lastname: Chen
authors.affiliation: Plant Stress and Germplasm Development Unit, USDA-ARS, Lubbock, TX, 79415, USA.
authors.forename: Zhanguo
authors.initials: Z
authors.lastname: Xin
authors.affiliation: Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX, 79409, USA.|Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan, 430079, China.
authors.forename: Huazhong
authors.initials: H
authors.lastname: Shi
mesh_terms: D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D002462:Cell Membrane / Q000235:genetics / Q000378:metabolism; D018506:Gene Expression Regulation, Plant / Q000235:genetics / Q000502:physiology; D006360:Heat-Shock Proteins / Q000235:genetics / Q000378:metabolism*; D006358:Hot Temperature; D020871:RNA Stability / Q000235:genetics* / Q000502:physiology
chemical_list: D029681:Arabidopsis Proteins; D006360:Heat-Shock Proteins
keywords: 
  Arabidopsis thaliana
  ; PUT3; gene regulation; heat stress; mRNA stability; polyamine transport; polyamines