title: Primary evidence for involvement of IP3 in heat-shock signal transduction in Arabidopsis.
abstract: The role of inositol 1,4,5-trisphosphate (IP(3)) in transducing heat-shock (HS) signals was examined in Arabidopsis. The whole-plant IP(3) level increased within 1 min of HS at 37 degrees C. After 3 min of HS, the IP(3) level reached a maximum 2.5 fold increase. Using the transgenic Arabidopsis plants that have AtHsp18.2 promoter-beta-glucuronidase (GUS) fusion gene, it was found that the level of GUS activity was up-regulated by the addition of caged IP(3) at both non-HS and HS temperatures and was down-regulated by the phospholipase C (PLC) inhibitors {1-[6-((17beta-3-Methoxyestra-1,3,5(10)-trien-17-yl)amino)hexyl]-2,5-pyrrolidinedione}(U-73122). The intracellular-free calcium ion concentration ([Ca(2+)](i)) increased during HS at 37 degrees C in suspension-cultured Arabidopsis cells expressing apoaequorin. Treatment with U-73122 prevented the increase of [Ca(2+)](i) to some extent. Above results provided primary evidence for the possible involvement of IP(3) in HS signal transduction in higher plants.
authors.affiliation: Institute of Genetics and Physiology, Hebei Academy of Agricultural Sciences, Shijiazhuang 050051, China.
authors.forename: Hong Tao
authors.initials: HT
authors.lastname: Liu
authors.forename: Fei
authors.initials: F
authors.lastname: Gao
authors.forename: Shu Juan
authors.initials: SJ
authors.lastname: Cui
authors.forename: Jin Long
authors.initials: JL
authors.lastname: Han
authors.forename: Da Ye
authors.initials: DY
authors.lastname: Sun
authors.forename: Ren Gang
authors.initials: RG
authors.lastname: Zhou
mesh_terms: D000331:Aequorin / Q000378:metabolism / Q000494:pharmacology; D001059:Apoproteins / Q000378:metabolism / Q000494:pharmacology; D017360:Arabidopsis / Q000201:enzymology / Q000254:growth & development / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000037:antagonists & inhibitors / Q000235:genetics; D002118:Calcium / Q000378:metabolism; D002478:Cells, Cultured; D004963:Estrenes / Q000494:pharmacology; D018506:Gene Expression Regulation, Plant; D005966:Glucuronidase / Q000378:metabolism; D006360:Heat-Shock Proteins / Q000235:genetics; D018869:Heat-Shock Response; D006358:Hot Temperature; D015544:Inositol 1,4,5-Trisphosphate / Q000031:analogs & derivatives / Q000378:metabolism* / Q000494:pharmacology; D052139:Intracellular Calcium-Sensing Proteins / Q000378:metabolism / Q000494:pharmacology; D030821:Plants, Genetically Modified / Q000378:metabolism; D011401:Promoter Regions, Genetic; D011760:Pyrrolidinones / Q000494:pharmacology; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D011994:Recombinant Proteins / Q000378:metabolism / Q000494:pharmacology; D015398:Signal Transduction; D010738:Type C Phospholipases / Q000037:antagonists & inhibitors / Q000378:metabolism
chemical_list: D001059:Apoproteins; D029681:Arabidopsis Proteins; D004963:Estrenes; C446287:HSP18.2 protein, Arabidopsis; D006360:Heat-Shock Proteins; D052139:Intracellular Calcium-Sensing Proteins; D011760:Pyrrolidinones; D011993:Recombinant Fusion Proteins; D011994:Recombinant Proteins; C060014:apoaequorin; C060229:1-(6-((3-methoxyestra-1,3,5(10)-trien-17-yl)amino)hexyl)-1H-pyrrole-2,5-dione; C061868:inositol 1,4,5-trisphosphate 1-(2-nitrophenyl)ethyl ester; D000331:Aequorin; D015544:Inositol 1,4,5-Trisphosphate; D010738:Type C Phospholipases; D005966:Glucuronidase; D002118:Calcium