陆地棉光合系统ⅡGhPsbS基因功能初步探究

Preliminary Study on the Function ofⅡGhPsbS Gene in Photosynthetic Sys-tem of Upland Cotton

为探究棉花光合系统Ⅱ基因GhPsbS,在不同温度条件下的基因相对表达量以及不同温度对野生型和转基因烟草植株的影响。本研究利用转基因GhPsbS烟草(Nicotiana tabacum xanthin) T4代为材料,在生长50 d左右,取生长状况相同的转基因植株60株,在光照培养箱中,温度设为35℃处理0、1、3、6、18、36 h,分别取样,提取RNA,反转c DNA,采用qPCR技术分析转基因植株在不同温度处理下的基因相对表达量并采用LI-6400型便携式光合系统仪(美国Li-cor公司)测量不同处理时间的烟草的光合特性。结果表明:在35℃温度处理条件下,抑制该基因的相对表达量。通过对光合数据分析可知,转基因烟草植株的气孔导度(Gs)、蒸腾速率(Tr)呈现明显升高趋势。在高温条件下转基因植株的净光合速率高于野生型。而温度对于转基因和野生型胞间CO_(2)浓度(Ci)关系不大。推测棉花GhPsbS基因参与调控烟草植株的光合作用。研究结果为探究如何提高棉花光能利用效率及增加作物产量提供一定的理论基础。

In order to explore the cotton photosynthetic systemⅡgene GhPsbS,the relative gene expression under different temperature conditions and the effect of different temperatures on wild-type and transgenic tobacco plants.This study uses the T 4 generation of transgenic GhPsbS tobacco(Nicotiana tabacum xanthin)and wild-type tobaccoplants(commonwild-type,WT)asmaterials.Inalightincubator,whenthetransgenicplantsare significantly different from the wild-type plants(grow to 50 days around),take 60 transgenic and wild-type plants with the same growth status,set the temperature to 35℃,and treat them for 0,1,3,6,18,36 h,3 replicates for each treatment,take samples separately,and place the samples put it in the refrigerator at-80℃for later use.Using qPCR tech-nology to analyze the relative gene expression levels of the two under different temperature treatments and the lev-el of expression levels in different parts of the cotton plant.The LI-6400 portable photosynthetic system instru-ment(Li-cor,USA)was used to measure the photosynthetic characteristics of tobacco with different treatment times.The results showed that the relative expression of the gene was inhibited under the condition of 35℃ tem-perature treatment.Through the analysis ofphotosynthetic data,it can be seen that the stomatal conductance(G s)and transpiration rate(T_(r))of transgenic tobacco plants show a significant increasing trend.Under high temperature con-ditions,the net photosynthetic rate of transgenic plants is higher than that of wild type.The temperature has little relationship with the intercellular CO_(2) concentration(C_(i))of transgenic and wild-type cells.It is speculated that the cotton GhPsbS gene is involved in regulating the photosynthesis of tobacco plants.The research results provide a theoretical basis for exploring how to improve the efficiency of cotton light use and increase crop yield.