Primary evidence for involvement of IP3 in heat-shock signal transduction in Arabidopsis.
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.
Liu
Hong Tao
HT
Institute of Genetics and Physiology, Hebei Academy of Agricultural Sciences, Shijiazhuang 050051, China.
Gao
Fei
F
Cui
Shu Juan
SJ
Han
Jin Long
JL
Sun
Da Ye
DY
Zhou
Ren Gang
RG
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
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