基于转录组测序筛选新疆野苹果组培苗应答冻害光合特性相关基因  

Screening of freezing stress-responsive genes related to photosynthesis in in vitro seedlings of Malus sieversii via RNA-seq

作　　者：马红喜 刘俐君 苏永峰 张德恩 袁引燕 鲁晓燕[1] MA Hongxi;LIU Lijun;SU Yongfeng;ZHANG Deen;YUAN Yinyan;LU Xiaoyan(Horticulture of Agriculture College of Shihezi University/Key Laboratory of Special Fruits and Vegetables Cultivation Physiology and Germplasm Resources Utilization,Xinjiang Production and Construction Corps,Shihezi 832000,Xinjiang,China)

机构地区：[1]石河子大学农学院园艺系·新疆生产建设兵团特色果蔬栽培生理与种质资源利用重点实验室,新疆石河子832000

出　　处：《果树学报》2022年第9期1529-1539,共11页Journal of Fruit Science

基　　金：国家自然科学基金委NSFC-新疆联合基金(培育)项目(U1703116)。

摘　　要：【目的】探究新疆野苹果组培苗光合特性对冻害胁迫的响应,筛选光合特性相关应答基因。【方法】以单株系的新疆野苹果组培苗为材料,在-3℃模拟冻害条件下,观察及检测对照和0、3、6、12、24 h处理的新疆野苹果组培苗的形态、叶绿素含量、光系统Ⅱ的最大量子产量(F_(v)/F_(m))参数和以吸收光能为基础的光系统Ⅱ的性能指数(PIabs)的变化,并对前5个处理组培苗叶片进行转录组测序分析。【结果】-3℃模拟冻害胁迫下新疆野苹果组培苗叶片在12 h时开始卷缩,处理24 h时叶绿素含量显著下降,叶绿素a/b显著上升;不同处理时间点Fv/Fm与PIabs的值均显著低于对照,通过转录组测序筛选到58个参与光合调控的差异基因,其中响应光系统Ⅱ的基因有18个,响应光系统Ⅰ的基因有12个,光合电子传递链相关基因有13个,ATP合成酶相关基因有3个,细胞色素b6f相关基因有12个。同时得到PsbQ(Msi_13A005910)与PsbY(BGI_novel_G011171)基因并在冻害胁迫中极显著上调表达。根据富集结果选取7个光合相关差异表达基因,经qRT-PCR验证,基因表达趋势与转录组测序结果一致。【结论】新疆野苹果组培苗在-3℃模拟冻害条件下,F_(v)/F_(m)与PIabs均显著下降,通过转录组测序筛选到58个光合调控相关显著差异表达基因,其中PsbQ与PsbY发生极显著上调表达。PsbQ与PsbY可能会通过光氧化与光保护缓解冻害对组培苗叶绿体及光合作用产生影响。【Objective】In order to explore the response of photosynthesis of Malus sieversii seedlings to freezing stress, we screened the responsive genes related to photosynthesis through transcriptomic analysis.【Methods】In vitro seedlings of a single plant line were used as materials. Under simulated freezing stress at-3 ℃, the changes in morphology, chlorophyll content, PSII maximum photochemical efficiency(F_(v)/F_(m)) and the performance index(PIabs) of photosystem Ⅱ of the in vitro seedlings of M.sieversii exposed to the freezing stress for 0, 3, 6, 12 and 24 h(seedlings under 25 ℃ as control) were analyzed, and the RNA-seq was performed on the leaves of the seedlings under the above five treatments.【Results】Under the freezing stress, the edge and top of the leaves began to shrink at 12 h. Compared with CK, the content of chlorophyll a decreased significantly by 16.2% within 24 h, and had no significant difference among the other four time points. Compared with CK, the content of chlorophyll b increased significantly by 52% at 0 h, but did not change significantly at 3 h, while at 6 h, 12 h and 24 h,it decreased significantly by 12.3%, 28.6% and 36.7% respectively. The change trend of total chlorophyll content was completely consistent with chlorophyll b. Carotenoid content was significantly lower than that of the control, and decreased by 23.5%, 23.5%, 25.5%, 19.6% and 29.4% at 0, 3, 6, 12 and 24 h,respectively. Compared with CK, chlorophyll a/b ratio decreased significantly at 0 h and 3 h but increased significantly at 12 h and 24 h by 14.9% and 14.1%, respectively. Under simulated freezing stress,the fluorescence images of the leaves gradually changed from dark blue to light blue and to blue-green from CK to 24 h treatment, indicating that the photochemical efficiency gradually decreased. F_(v)/F_(m)decreased significantly by 7.9%, 12.3%, 12.8%, 19.9% and 29.4% at 0, 3, 6, 12 and 24 h, respectively.Compared with CK, the PIabs decreased significantly by 61.2%, 63.7%, 78.3%, 77.2% and 87.7% at 0,3,

关 键 词：新疆野苹果 冻害胁迫 光合特性 转录组测序 

分 类 号：S661.1[农业科学—果树学]