摘要
油菜素内酯(brassinosteroids,BRs)是一种广泛分布于多种植物体内的激素。Brassinosteroid insensitive 1(BRI1)是BR信号通路的主要信号受体,在植物生长发育和胁迫应答中起着至关重要的作用。研究以番茄品种Micro-Tom(MT)和SlBRI1过表达株系(Atrd29A:SlBRI1)为试验材料,探讨低温对光合特性、叶绿素荧光参数以及抗寒基因的影响,旨在揭示Atrd29A启动子驱动SlBRI1基因对低温胁迫的响应规律。结果表明,(1)低温胁迫提高了MT植株SlBRI1的表达量,而Atrd29A:SlBRI1植株SlBRI1表达量更高。低温胁迫5 d导致所有植株出现萎蔫,而且Atrd29A:SlBRI1植株萎蔫程度更轻,恢复得更好。(2)低温胁迫导致所有番茄幼苗的净光合速率(P_(n))、气孔导度(G_(s))、蒸腾速率(T_(r))、PSⅡ最大光化学效率(F_(v)/F_(m))、实际光化学效率(ΦPSⅡ)、光能捕获效率(F_(v)′/F_(m)′)和光化学荧光猝灭系数(q P)都较大幅度地下降;在低温胁迫第5天,SlBRI1过表达株系这些指标均显著性高于MT植株。同时,SlBRI1过表达株系的细胞间CO 2浓度(C i)显著低于MT。(3)同等条件下SlICE1、SlCBF1、SlCBF3和SlDRCI7基因表达水平显著上升,并且通过低温处理后的SlBRI1转基因植株中SlICE1、SlCBF1、SlCBF3和SlDRCI7基因表达水平均显著高于MT植株。表明Atrd29A诱导SlBRI1表达能够提高SlBRI1表达水平,缓解低温胁迫对植株光合作用和叶绿素荧光参数的影响,增强番茄植株抗寒能力。
Brassinosteroids(BRs)is a kind of hormone widely distributed in a variety of plants.Brassinosteroid insensitive 1(BRI1)is the main signal receptor of BR signaling pathway,which plays a crucial role in plant growth and development and stress response.In this study,we used tomato varieties Micro-Tom(MT)and SlBRI1 overexpression plants(Atrd29A:SlBRI1)as experimental materials to investigate the effects of low temperature on photosynthetic characteristics,chlorophyll fluorescence parameters and cold resistance genes,in order to reveal the response of SlBRI1 gene driven by Atrd29A promoter to low temperature stress.The results showed that,(1)low temperature stress increased the expression of SlBRI1 in MT plants,while the expression of SlBRI1 in Atrd29A:SlBRI1 plants were higher than that of MT plants.Low temperature stress for 5 days resulted in wilting of all plants,and Atrd29A:SlBRI1 plants wilted less and recovered better.(2)The net photosynthetic rate(P_(n)),stomatal conductance(G_(s)),transpiration rate(T_(r)),maximum photochemical efficiency of PSⅡ(F_(v)/F_(m)),actual photochemical efficiency(ΦPSⅡ),light capture efficiency(F_(v)′/F_(m)′)and photochemical fluorescence quenching coefficient(q P)of all tomato seedlings were significantly decreased under low temperature stress.On the 5th day of low temperature stress,these indexes of SlBRI1 overexpressing plants were significantly higher than those of MT plants.Meanwhile,the intercellular CO 2 concentration(C i)of SlBRI1 overexpression lines was significantly lower than that of MT.(3)The expression levels of transgenic plants SlICE1,SlCBF1,SlCBF3 and SlDRCI7 were significantly increased under the same condition,and the expression levels of SlICE1,SlCBF1,SlCBF3 and SlDRCI7 in SlBRI1 transgenic plants after low temperature treatment were significantly higher than those in MT plants.The results indicated that the expression of SlBRI1 induced by Atrd29A could improve the expression of SlBRI1,alleviate the effects of low temperature stress on plant photosynthesi
作者
杨文文
冯梦颖
瞿芮
刘心雨
聂书明
YANG Wenwen;FENG Mengying;QU Rui;LIU Xinyu;NIE Shuming(Key Laboratory of Southwest China Wildlife Resources Conservation,College of Life Science,China West Normal University,Nanchong,Sichuan 637000,China)
出处
《西北植物学报》
CAS
CSCD
北大核心
2023年第11期1842-1849,共8页
Acta Botanica Boreali-Occidentalia Sinica
基金
西华师范大学博士启动项目(19E051)。
