AgNO_(3)暴露对红车轴草光合作用的影响  

Effects of AgNO_(3) Exposure on Photosynthesis of Trifolium pratense L.

作　　者：于川 莫凡 高建政 崔明 李海波[3] Yu Chuan;Mo Fan;Gao Jianzheng;Cui Ming;Li Haibo(Tianjin Eco-Environmental Monitoring Center,Tianjin 300191,China;School of Environmental Science and Engineering,Nankai University,Tianjin 300350,China;College of Resources and Civil Engineering,Northeast University,Shenyang 110004,China)

机构地区：[1]天津市生态环境监测中心,天津300191 [2]南开大学环境科学与工程学院,天津300350 [3]东北大学资源与土木工程学院,沈阳110004

出　　处：《生态毒理学报》2023年第5期305-319,共15页Asian Journal of Ecotoxicology

基　　金：天津市生态环境局2019年引滦流域监督管理项目(TGPC-2019-D-0409)。

摘　　要：从光合相关参数、显/超微结构和基因表达等方面探索了AgNO3对红车轴草光合作用的影响。光合色素含量、光系统Ⅱ最大量子效率(F_(v)/F_(m))、核酮糖-1,5-二磷酸核酮糖羧化酶活性和根长等指标在高浓度AgNO3(588 μmol·L^(-1))作用下分别降低了22.36%(叶绿素a)、18.6%(叶绿素b)、89.53%(Fv/Fm)、80.13%(核酮糖-1,5-二磷酸核酮糖羧化酶活性)和62.47%(根长)。然而在29 μmol·L^(-1)AgNO_(3)暴露下,相比于对照组,叶绿素a含量、叶绿素b含量、F_(v)/F_(m)、核酮糖-1,5-二磷酸核酮糖羧化酶活性和根长分别增加了32.68%、38.37%、30.63%、79.11%和159.53%(低促高抑,即毒物兴奋效应)。另外,AgNO_(3)明显破坏了红车轴草的细胞结构,呈现为叶绿体的解体与细胞内容物的聚集。转录组分析鉴别到了光合相关基因的差异表达(例如SIGE、HD16和PSBQ),表明红车轴草积极调控基因表达以应对光合抑制。蛋白-蛋白相互作用(protein-protein interaction,PPI)分析表明PETC、PSBO_(1)与PSBO_(2)为核心光合抗逆基因,STRING分析显示,AgNO_(3)显著影响了乙醇酸通路、光呼吸和CO_(2)固定等生物过程。本研究系统探索了AgNO_(3)暴露对红车轴草光合作用的影响机制,可以加深AgNO_(3)对植物毒性作用的理解。This research explored the effects of AgNO_(3) on photosynthesis of red clover in terms of photosynthesis related parameters,microstructure/ultrastructure,and gene expression level.The photosynthetic pigment content,photosystemⅡmaximum quantum efficiency(Fv/Fm),rubisco activity,and root length were decreased by 22.36%(chlorophyll a),18.6%(chlorophyll b),89.53%(F_(v)/F_(m)),80.13%(rubisco activity),and 62.47%(root length)un-der high concentration of AgNO3(588μmol·L^(-1)),respectively.However,AgNO_(3) exposure at 29μmol·L^(-1),com-pared to the controls,significantly increased chlorophyll a content,chlorophyll b content,F_(v)/F_(m),rubisco activity,and root length up to 32.68%,38.37%,30.63%,79.11%,and 159.53%,respectively(i.e.,hormesis effect).In ad-dition,AgNO_(3) exposure significantly damaged the cell structure of red clover,such as the disintegration of chloro-plasts and aggregation of intracellular substances.Transcriptome analysis identified the differential expression of several photosynthesis related genes,such as SIGE,HD16,and PSBQ,indicating that red clover actively regulated gene expression to cope with photosynthesis inhibition.Finally,protein-protein interaction(PPI)was carried out,and PETC,PSBO1 and PSBO_(2) were identified as core photosynthetic stress resistance genes.STRING analysis verified the affected biological processes such as glycolic acid pathway,photorespiration,and CO_(2) fixation.This study systematically explored the impact mechanism of AgNO_(3) exposure on red clover photosynthesis,which can provide insights on the toxicity mechanisms of AgNO_(3) on plants.

关 键 词：AgNO_(3) 红车轴草 光合作用 亚细胞结构 基因调控 

分 类 号：X171.5[环境科学与工程—环境科学]