摘要
为揭示可变剪接机制参与植物耐旱性的内在机制,以高表达转玉米C_(4)型磷酸烯醇式丙酮酸羧化酶(phosphoenolpyruvate carboxylase, PEPC)基因(C_(4)-PEPC)水稻(PC)和受体"Kitaake"(WT)为材料,通过盆栽和水培试验,研究外施可变剪接抑制剂大环内酯类(pladienolide B, PB)联合干旱处理下,功能叶片的光合参数、总可溶性糖及其组分、主要抗氧化酶活性以及抗氧化物质含量、Ca^(2+)、NO、H_(2)O_(2)、ABA含量、与蔗糖非发酵1 (sucrose nonfermenting-1,SNF1)相关蛋白激酶(SNF1-related protein kinase 3s, SnRK3s)以及剪接因子基因表达的变化。结果表明:在盆栽试验中,与单独自然干旱处理(drought stress, DS)相比,在孕穗期外施0.5μmol L^(–1)PB联合干旱处理(DS+PB),显著下降了供试水稻的产量及其构成因子的数值,其中,在DS+PB处理下, PC的株高、穗数、每穗实粒重和单株产量均显著高于WT。在水培试验中,与10%PEG-6000模拟干旱处理(PEG)相比,外施0.5μmol L^(–1) PB和10%PEG-6000模拟干旱处理(PEG+PB),均显著降低了供试水稻功能叶片的净光合速率(Pn)、相对含水量、总可溶性糖含量、脯氨酸含量、SOD酶活性、POD酶活性、CAT酶活性、PEPC酶活性、糖组分(蔗糖、葡萄糖、果糖含量)、Ca^(2+)、NO和H_(2)O_(2)的含量,其中, PC中3个糖组分以及钙离子含量始终高于WT。与PEG处理相比, PEG+PB处理也导致水稻叶片内糖信号SnRK2s基因(SAPK8和SAPK9)和3个SnRK1基因表达量下降,其中PC的SAPK8、SAPK10、OsK1a和OsK24表达均高于WT;进一步10mmolL^(–1)EGTA钙离子螯合剂引入实验证明,钙离子通过调节剪接因子相关基因的表达参与水稻干旱响应。相关性分析也表明,PC中钙离子含量分别与叶片可溶性蛋白含量、ABA含量以及剪接因子RS33的表达水平呈显著或极显著相关。综上,可变剪接参与水稻干旱响应,水稻可通过叶内糖信号SnRK1s和SnRK2s基因以及钙离子,参与调节剪接因子
To investigate the intrinsic mechanism of alternative splicing(AS)participated in drought tolerance in plants,the effects of macrolides pladienolide B(PB,one of the AS inhibitors)were studied using the phosphoenolpyruvate carboxylase(C4-PEPC)rice(PC)and"Kitaake"(WT)rice lines in pot experiments and hydroponics experiments,respectively.The changes of photosynthetic parameters,total soluble sugar and sugar components contents,some main antioxidant enzyme activities and antioxidant contents,Ca^(2+),NO,H_(2)O_(2),ABA contents,transcript levels of sucrose nonfermenting-1(SNF1)-related protein kinases(SnRKs),arginine/serine-rich proteins(SR proteins),and PEPC both in C4 and C3 type of the functional leaves in rice lines were measured.Agronomic traits of the WT and PC were recorded in the mature period.In pot experiment,compared with the natural drought treatment alone,the treatment of 0.5μmol L^(–1) PB with drought at booting stage had a significant decline on agronomic traits of the tested rice.Among them,plant height,panicle number per plant,filled grain number per panicle,and grain yield per plant in PC were significantly higher than those of WT.In the hydroponics experiment with 0.5μmol L^(–1) PB combined with 10%mmol L^(–1) polyethylene glycol 6000(PEG-6000)to simulate drought stress,compared with PEG treatment,net photosynthetic rate,relative water content,total soluble sugar content,proline content,SOD activity,POD activity,CAT activity,and PEPC activity were significantly increased in PC than those of WT.Similarly,the contents of sucrose,glucose,fructose,and Ca2+of leaves in PC lines were significantly higher than those of WT.It was noteworthy that the relative gene expression levels of C4-PEPE,Osppc2a,Sn RK2s(SAPK8 and SAPK9),SnRK1s(OsK1a,OsK24,and OsK35),and SR proteins(SR33,SR40,RS29,RS2 Z21,and RS2Z38)under PEG+PB treatment were significantly lower than those under PEG treatment.It was further verified by using 10 mmol L^(–1) EGTA experiments[Ethylene glycolbis(aminoethylether)-tetra-acetic acid,a
作者
宋凝曦
李霞
王净
吴博晗
曹悦
杨杰
谢寅峰
SONG Ni-Xi;LI Xia;WANG Jin;WU Bo-Han;CAO Yue;YANG Jie;XIE Yin-Feng(Institute of Food Crops,Jiangsu Academy of Agricultural Sciences,Jiangsu High Quality Rice Engineering Technology Research Center,Nanjing Branch of National Center for Rice Improvement,Nanjing 210014,Jiangsu,China;College of Biology and Environment,Nanjing Forestry Univer-sity,Nanjing 210037,Jiangsu,China;Collaborative Innovation Center for Modern Production Technology of Grain Crops of Jiangsu Province,Yangzhou 225009,Jiangsu,China;School of the Environment and Safety Engineering,Jiangsu University,Zhenjiang 212013,Jiangsu,China;School of Life Sciences,Nanjing Agricultural University,Nanjing 210095,Jiangsu,China)
出处
《作物学报》
CAS
CSCD
北大核心
2021年第10期1927-1940,共14页
Acta Agronomica Sinica
基金
国家自然科学基金项目(31571585)
国家重点研发计划项目(2016YFD0300501-03)资助。
关键词
水稻
可变剪接
磷酸烯醇式丙酮酸羧化酶
大环内酯
干旱
rice
alternative splicing
phosphate phosphoenolpyruvate carboxylase
macrolides pladienolide B
drought
