title: Contributions of PIP(2)-specific-phospholipase C and free salicylic acid to heat acclimation-induced thermotolerance in pea leaves.
abstract: The relationship between the accumulation in endogenous free salicylic acid (SA) induced by heat acclimation (37 degrees C) and the activity of PIP(2)-phospholipase C (PIP(2)-PLC; EC 3.1.4.3) in the plasma membrane fraction was investigated in pea (Pisum sativum L.) leaves. We focused our attention on the hypothesis that positive SA signals induced by heat acclimation may be relayed by PIP(2)-PLC. Heat acclimation induced an abrupt elevation of free SA preceding the activation of PLC toward PIP(2). Immunoblotting indicated a molecular mass with 66.5kDa PLC plays key role in the development of thermotolerance in pea leaves. In addition, some characterizations of PLC toward PIP(2) isolated from pea leaves with two-phase purification containing calcium concentration, pH and a protein concentration were also studied. Neomycin sulfate, a well-known PIP(2)-PLC inhibitor, was employed to access the involvement of PIP(2)-PLC in the acquisition of heat acclimation induced-thermotolerance. We were able to identify a PIP(2)-PLC, which was similar to a conventional PIP(2)-PLC in higher plants, from pea leaves suggesting that PIP(2)-PLC was involved in the signal pathway that leads to the acquisition of heat acclimation induced-thermotolerance. On the basis of these results, we conclude that the involvement of free SA may function as the upstream event in the stimulation of PIP(2)-PLC in response to heat acclimation treatment.
authors.affiliation: College of Food Science & Nutritional Engineering, China Agricultural University, Beijing 100083, China.
authors.forename: Hong-Tao
authors.initials: HT
authors.lastname: Liu
authors.forename: Wei-Dong
authors.initials: WD
authors.lastname: Huang
authors.forename: Qiu-Hong
authors.initials: QH
authors.lastname: Pan
authors.forename: Fang-Hua
authors.initials: FH
authors.lastname: Weng
authors.forename: Ji-Cheng
authors.initials: JC
authors.lastname: Zhan
authors.forename: Yan
authors.initials: Y
authors.lastname: Liu
authors.forename: Si-Bao
authors.initials: SB
authors.lastname: Wan
authors.forename: Yan-Yan
authors.initials: YY
authors.lastname: Liu
mesh_terms: D000064:Acclimatization / Q000502:physiology*; D002462:Cell Membrane / Q000378:metabolism; D004789:Enzyme Activation; D004791:Enzyme Inhibitors / Q000494:pharmacology; D006358:Hot Temperature; D008861:Microsomes / Q000378:metabolism; D009355:Neomycin / Q000494:pharmacology; D018532:Pisum sativum / Q000033:anatomy & histology / Q000201:enzymology / Q000378:metabolism*; D010650:Phenylalanine Ammonia-Lyase / Q000378:metabolism; D054801:Phosphoinositide Phospholipase C; D010727:Phosphoric Diester Hydrolases / Q000737:chemistry / Q000502:physiology*; D018515:Plant Leaves / Q000033:anatomy & histology / Q000187:drug effects / Q000378:metabolism; D020156:Salicylic Acid / Q000378:metabolism*; D015398:Signal Transduction
chemical_list: D004791:Enzyme Inhibitors; D010727:Phosphoric Diester Hydrolases; D054801:Phosphoinositide Phospholipase C; D010650:Phenylalanine Ammonia-Lyase; D009355:Neomycin; D020156:Salicylic Acid