高温强光对小麦叶绿体Deg1蛋白酶和D1蛋白的影响及水杨酸的调节作用  

Effect of heat and high irradiation stress on Deg1 protease and D1 protein in wheat chloroplasts and the regulating role of salicylic acid

作　　者：郑静静[1] 赵会杰[1] 胡巍巍[1] 赵雪娟[1] 赵一丹[1] 

机构地区：[1]河南农业大学生命科学学院,郑州450002

出　　处：《生态学报》2013年第9期2930-2935,共6页Acta Ecologica Sinica

基　　金：国家自然科学基金(30971725)

摘　　要：以小麦品种矮抗58为材料,采用0.3 mmol/L水杨酸(SA)溶液预处理灌浆期小麦叶片,以水预处理为对照,进行3种不同的光温处理:适宜温度中等光强(25℃,600μmol m-2 s-1)2 h、高温强光(38℃,1600μmol m-2 s-1)2h、高温强光2 h后置于适宜温度中等光强下恢复3h。测定不同光温条件下,小麦叶绿体的Deg1蛋白酶、D1蛋白和PSⅡ功能的变化及SA的调节效应。结果表明,高温强光胁迫导致Deg1蛋白酶和D1蛋白降解,PSⅡ功能发生可逆损伤。与对照相比,水杨酸预处理不仅能够抑制高温强光下小麦叶绿体Deg1蛋白酶和D1蛋白的降解,维持较高的PSⅡ原初光化学效率(Fv/Fm)、实际光化学效率(ΦPSⅡ)、电子传递速率和净光合速率(Pn),而且加快回到非逆境下PSⅡ功能的恢复。Wheat is one of the most important food crops in China and its production is crucial to ensure national food security.In the north of China,wheat plants often suffer from heat and high irradiation stress during grain-filling stage,leading to damage in photosynthetic apparatus and reduction of yield.Especially,the reaction center in photosystem Ⅱ(PS Ⅱ) is prone to various environmental stresses,and the extent of damage depends on the balance between injury and repair.The repair of PSⅡ needs fast turnover of D1 protein,which is the key component of PSⅡ.During the repair of PSⅡ,damaged D1 protein must be degraded and subsequently replaced by new copies quickly.It is well known that Deg1 protease plays an important role in cleavage of damaged D1 protein.However,the dynamic change in Deg1 protease under heat and high light stress is still largely unclear.In this study,we used wheat cultivar 'Aikang 58' to determine the effects of heat and high light stress on Deg1 protease and D1 protein levels and PSⅡ performance and further the regulation role of salicylic acid(SA) in the repair of PSⅡ.Wheat leaves of grain-filling stage were pretreated with 0.3 mmol/L SA and distilled water(as control) respectively and then subjected to three temperature and irradiation treatments: moderate temperature and irradiation(25℃,600 μmol m-2 s-1,MTI) for 2h,high temperature and irradiation(38℃,1600 μ mol m-2 s-1,HTI) for 2h,and HTI following by 3h MTI.Fluorescence parameters were measured using a chlorophyll fluorometer.The levels of Deg1 protease and D1 protein were analyzed by western-blotting analysis.The results showed that HTI treatment resulted in degradation of Deg1 protease and D1 protein and reversible damage to PSⅡ function.Compared with control,pretreatment with SA not only retarded degradation of Deg1 protease and D1 protein,maintained higher potential photochemical efficiency(Fv/Fm),actual photochemical efficiency(ΦPSⅡ),electron transfer rate(ETR) of PSⅡ and net photosynthetic rate(Pn) of wheat leav

关 键 词：小麦 高温强光胁迫 水杨酸 Deg1蛋白酶 D1蛋白 PSⅡ功能 

分 类 号：S512.1[农业科学—作物学]