高温胁迫对转反义LeGPAT番茄PSⅡ光化学活性的影响  

Photochemical Activity of PSⅡ in Antisense Tomato Depletion of LeGPAT under High Temperature Stress

作　　者：隋娜[1] 李萌[2] 孟庆伟[3] 

机构地区：[1]山东师范大学生命科学学院山东省植物逆境重点实验室,济南250014 [2]山东省农业科学院,济南250100 [3]作物生物学国家重点实验室,山东泰安271018

出　　处：《西北植物学报》2010年第4期719-724,共6页Acta Botanica Boreali-Occidentalia Sinica

基　　金：中国博士后基金(20090450155);山东省中青年科学家科研奖励基金(2009BSB02023);山东省博士后基金(200802009);作物生物学国家重点实验室开放课题(2008KF03)

摘　　要：以冷敏感植物番茄(Lycopersicon esculentumMill.)为材料,研究高温胁迫下转反义番茄甘油-3-磷酸酰基转移酶基因(LeGPAT)的番茄叶片膜脂含量、光合速率、荧光参数和叶黄素循环等的变化,以探讨LeGPAT表达与番茄植株耐热性的关系。结果表明:转反义基因株系磷脂酰甘油(PG)的饱和脂肪酸含量(16∶0+16∶1+18∶0)显著高于野生型;但不饱和脂肪酸含量(18∶1+18∶2+18∶3)却显著低于野生型。在45℃高温处理过程中,野生型和转反义基因的番茄植株净光合速率(Pn)、暗中最大光化学效率(Fv/Fm)和实际光化学效率ΦPSⅡ都显著降低,但野生型番茄降低幅度更大;同时野生型和转反义基因株系的非光化学猝灭(NPQ)及叶黄素循环脱环氧化状态(A+Z)/(V+A+Z)都增加,但反义株系比野生型增加更明显。研究发现,转基因番茄植株LeGPAT的表达被抑制,其饱和脂肪酸含量升高,而不饱和脂肪酸含量降低,高温胁迫下PSⅡ受到的伤害较轻光化学活性更高,植株抵抗高温的能力更强。Tomato was used to investigate the changes of membrane lipid content,Pn,chlorophyll fluorescence parameters and de-epoxidized ratio of the xanthophylls cycle of antisense tomato depletion of LeGPAT under high temperature stress.The content of saturated fatty acids（16∶0＋16∶1＋18∶0） of antisense tomato was higher than that of wild type（WT）;While the content of unsaturated fatty acids（18∶1＋18∶2＋18∶3） of antisense tomato was lower than that of WT.Pn,Fv/Fm and ΦPSⅡ of WT and antisense transgenic tomato plants significantly decreased at 45℃.The decrease was more obvious in the WT than in antisense transgenic plants.Both NPQ and the de-epoxidized ratio of the xanthophylls cycle,（A＋Z）/（V＋A＋Z）,increased in WT as well as in antisense transgenic plants at high temperature.NPQ and（A＋Z）/（V＋A＋Z） of antisense transgenic plants markedly increased relative to that of WT during high temperature stress.These results showed that increase of PG saturated fatty acid content by the depletion of LeGPAT was helpful in improving the thermal tolerance of tomato plants to high temperature.

关 键 词：高温胁迫 番茄甘油-3-磷酸酰基转移酶基因 番茄 PSⅡ光化学活性 

分 类 号：Q789[生物学—分子生物学]