摘要
为探究盐胁迫下OsDSR2 RNAi转基因水稻的生理特性和差异基因的表达调控,以中花11(ZH11)植株为对照,对OsDSR2 RNAi转基因水稻幼苗进行生理特性和转录组学分析,结果表明:正常条件下,ZH11和Os DSR2 RNAi转基因水稻中叶绿素含量和根部Na+/K+均显著低于ZH11,其他各项生理指标均没有显著性差异,而盐胁迫处理后,Os DSR2 RNAi转基因水稻中的叶绿素含量、可溶性糖(SS)含量、过氧化氢酶(CAT)活性与ZH11相比没有明显变化,但转基因植株中的细胞膜透性、丙二醛(MDA)含量、Na+/K+显著或极显著低于ZH11,脯氨酸(Pro)含量、超氧化物歧化酶(SOD)活性、过氧化物酶(POD)活性显著或极显著高于ZH11。Os DSR2 RNAi转基因水稻在盐胁迫前后共产生68个差异表达基因,其中有55个上调表达,13个下调表达。GO分析结果显示,差异表达基因主要富集在胁迫应激反应、分解代谢等生物学过程中。KEGG分析结果表明,差异表达基因主要参与类胡萝卜素生物合成、油菜素内酯生物合成以及表皮素,软木脂和蜡质生物合成代谢通路中,进一步通过RT-q PCR验证了Osb ZIP16、Os LEA3、RAB21等差异表达基因参与水稻的胁迫应答反应。综上,在生理层面上,Os DSR2 RNAi转基因水稻主要通过降低细胞膜透性、MDA含量和Na+/K+,增加Pro含量,提高SOD和POD活性,抑制叶绿素的降解来提高耐盐性;在分子水平上,Os DSR2主要通过脱落酸(ABA)、油菜素内酯(BR)信号通路参与调控Osb ZIP16、Os LEA3、RAB21等逆境相关基因的表达来提高苗期水稻的耐盐性,为进一步阐明Os DSR2参与调控水稻耐盐的详细分子机制奠定基础。
In order to explore the physiological characteristics and the transcriptional regulation of OsDSR2 RNAi transgenic rice under salt stress,we analyzed the physiological indicators and the transcriptome profiles of OsDSR2 RNAi transgenic rice seedlings compared to Zhonghua 11(ZH11)plants.Under normal conditions,the chlorophyll content and root Na+/K+of ZH11 and OsDSR2 RNAi transgenic rice were significantly lower than those of ZH11,and there was no significant difference in other physiological indexes.After salt stress treatments,no significant difference on the content of chlorophyll,soluble sugar(SS)and catalase(CAT)activity of OsDSR2 RNAi transgenic rice to ZH11 was detected,while the content of cell membrane permeability,malondialdehyde(MDA)and Na+/K+in transgenic rice significantly or extremely significantly lower than those of ZH11;the content of Proline(Pro),superoxide dismutase(SOD)activity and peroxidase(POD)activity were significantly or extremely significantly higher than those of ZH11.The transcriptome analysis revealed 68 differentially expressed genes in OsDSR2 RNAi transgenic plants before and after salt stress treatment,55 genes of which were up-regulated and 13 genes of which were down-regulated.GO analysis showed that the differentially expressed genes were enriched in stress response,catabolism and other biological processes.KEGG analysis showed that the differentially expressed genes were mainly involved in the biosynthesis of carotenoids,brassinolactone and the biosynthesis of epidermal,cork and wax biosynthesis pathways.The differential expression of OsbZIP16,OsLEA3,RAB21 and differently expressed genes under treatments was further verified by RT-qPCR.In summary,on the physiological level,OsDSR2 RNAi transgenic rice mainly improved salt tolerance by reducing membrane permeability,MDA content and Na+/K+,increasing Pro content,increasing SOD and POD activity,and inhibiting chlorophyll degradation.On the molecular level,OsDSR2 was mainly involved in regulating the expression of stress related gen
作者
楚乐乐
罗成科
李芳兰
路旭平
马天利
李培富
CHU Le-le;LUO Cheng-ke;LI Fang-lan;LU Xu-ping;MA Tian-li;LI Pei-fu(Agricultural College of Ningxia University/Key Laboratory of Modern Molecular Breeding of Dominant Characteristic Crops in Ningxia,Yinchuan 750021)
出处
《植物遗传资源学报》
CAS
CSCD
北大核心
2020年第4期954-965,共12页
Journal of Plant Genetic Resources
基金
国家自然科学基金(31560297)。
