The Patatin-Containing Phospholipase A pPLAIIα Modulates Oxylipin Formation and Water Loss in Arabidopsis thaliana  

作　　者：Wen-Yu Yang Yong Zheng Sung Chul Bahn Xiang-Qing Pan Mao-Yin Li Hieu Sy Vu Mary R.Roth Brad Scheu Ruth Welt Yue-Yun Hong Xue-Min Wang 

机构地区：[1]Department of Biology,University of Missouri,St Louis,MO 63121,USA [2]Donald Danforth Plant Science Center,St Louis,MO 63132,USA [3]Hubei Key Laboratory of Genetic Regulation and Integrative Biology,College of Life Sciences,HuaZhong Normal University,Wuhan 430079,China [4]Kansas Lipidomics Research Center,Division of Biology,Kansas State University,Manhattan,KS 66506,USA [5]National Key Laboratory of Crop Genetic Improvement,Huazhong Agricultural University,Wuhan 430070,China

出　　处：《Molecular Plant》2012年第2期452-460,共9页分子植物（英文版）

基　　金：This work was supported by grants from the National Science Foundation （MCB-0920681; IOS-0818740） and the US Department of Energy （DE-SC0001295）. The Kansas Lipidomics Research Center＇s research was supported by grants from the National Science Foundation （MCB-0920663, DBI-0521587, and Kansas Experimental Program to Stimulate Competitive Research Award EPS-0236913）, with support from the State of Kansas through the Kansas Technology Enterprise Corporation and Kansas State University, as well from US Public Health Service Grant P20 RR-016475 from the IDeA Network of Biomedical Research Excellence program of the National Center for Research Resources. No conflict of interest declared.

摘　　要：The patatin-related phospholipase A （pPLA） hydrolyzes membrane glycerolipids to produce monoacyl compounds and free fatty acids. Phospholipids are cleaved by pPLAIIα at the sn-1 and sn-2 positions, and galactolipids, including those containing oxophytodienoic acids, can also serve as substrates. Ablation of pPLAIIα decreased lysophosphatidylcholine and lysophosphatidylethanolamine levels, but increased free linolenic acid. pPLAIIα-deficient plants displayed a higher level of jasmonic acid and methyl jasmonate, as well as the oxylipin-biosynthetic intermediates 13-hydroperoxylinolenic acid and 12-oxophytodienoic acid than wild-type （WT） plants. The expression of genes involved in oxylipin production was also higher in the pPLAIlec-deficient mutant than in WT plants. The mutant plants lost water more quickly than WT plants. The stomata of WT and mutant plants responded similarly to abscisic acid. In response to desiccation, the mutant and WT leaves produced abscisic acid at the same rate, but, after 4 h of desiccation, the jasmonic acid level was much higher in mutant than WT leaves. These results indicate that pPLAIIα negatively regulates oxylipin production and suggest a role in the removal of oxidatively modified fatty acids from membranes.The patatin-related phospholipase A （pPLA） hydrolyzes membrane glycerolipids to produce monoacyl compounds and free fatty acids. Phospholipids are cleaved by pPLAIIα at the sn-1 and sn-2 positions, and galactolipids, including those containing oxophytodienoic acids, can also serve as substrates. Ablation of pPLAIIα decreased lysophosphatidylcholine and lysophosphatidylethanolamine levels, but increased free linolenic acid. pPLAIIα-deficient plants displayed a higher level of jasmonic acid and methyl jasmonate, as well as the oxylipin-biosynthetic intermediates 13-hydroperoxylinolenic acid and 12-oxophytodienoic acid than wild-type （WT） plants. The expression of genes involved in oxylipin production was also higher in the pPLAIlec-deficient mutant than in WT plants. The mutant plants lost water more quickly than WT plants. The stomata of WT and mutant plants responded similarly to abscisic acid. In response to desiccation, the mutant and WT leaves produced abscisic acid at the same rate, but, after 4 h of desiccation, the jasmonic acid level was much higher in mutant than WT leaves. These results indicate that pPLAIIα negatively regulates oxylipin production and suggest a role in the removal of oxidatively modified fatty acids from membranes.

关 键 词：patatin-related phospholipase A oxidative modified lipids jasmonate synthesis water loss Arabidopsis thaliana. 

分 类 号：S157.1[农业科学—土壤学] Q344.13[农业科学—农业基础科学]