不同水稻抗性淀粉含量差异的转录组学解析  

Transcriptome analysis of differences in resistant starch content in different rice cultivars

作　　者：王蕊 张风琴 田蕾 罗成科 李培富 马天利 WANG Rui;ZHANG Fengqin;TIAN Lei;LUO Chengke;LI Peifu;MA Tianli(College of Agriculture,Key Laboratory of Modern Molecular Breeding of Advantaged Characteristic Crops in Ningxia,Ningxia University,Yinchuan 750021,China)

机构地区：[1]宁夏大学农学院/宁夏优势特色作物现代分子育种重点实验室,宁夏银川750021

出　　处：《江西农业大学学报》2024年第5期1109-1123,共15页Acta Agriculturae Universitatis Jiangxiensis

基　　金：宁夏回族自治区育种专项(2018NYYZ0302)。

摘　　要：【目的】抗性淀粉是功能性水稻研究的热点品质性状之一。旨在研究水稻籽粒灌浆过程中不同抗性淀粉含量品种之间的差异表达基因及可能参与的调控通路,探究水稻抗性淀粉合成的规律和分子机制。【方法】分别对高抗性淀粉粳稻品种JTD和低抗性淀粉粳稻品种宁粳28号(NJ28)在籽粒灌浆中后期2个时间点(10 d和16 d),每个时间点每个样品3次重复,共12个样品进行转录组学测序和分析。【结果】NJ28和JTD在灌浆10 d相比有1326个差异表达基因(DEGs),包含986个上调DEGs和340个下调DEGs;在16 d时有1158个DEGs,包含384个上调DEGs和786个下调DEGs;在10 d和16 d共同变化的DEGs 689个,包含435个上调DEGs和254个下调DEGs。GO功能和KEGG富集分析发现DEGs主要参与淀粉代谢和脂肪酸代谢,例如α-淀粉酶、β-淀粉酶、α-葡萄糖苷酶、β-葡萄糖苷酶、异淀粉酶、脂肪酸延长和降解相关酶等。利用qRT-PCR对3个基因进行验证发现,其mRNA表达趋势均与转录组分析中的表达趋势一致。利用气质联用仪对36个脂肪酸进行定量测定,发现包括油酸在内的7个脂肪酸在高抗性淀粉品种中含量较高。【结论】筛选到一些可能参与抗性淀粉合成的候选基因和重要脂肪酸,为深入理解水稻籽粒中RS合成、其与非淀粉物质脂肪酸之间的关联提供了研究思路和分子基础,为制备具有酶抗性结构和低升糖指数的淀粉类食品提供理论依据。[Objective]Resistant starch is one of the hot quality traits in functional rice research.By investigating the differentially-expressed genes and possible regulatory pathways among rice varieties with different resistant starch content during grain filling,this study aims to explore the rules and molecular mechanisms of resistant starch synthesis in rice.[Method]A high starch japonica rice variety JTD and a low resistance starch japonica rice variety Ningjing 28(NJ28)were used for transcriptome sequencing and analysis at two time points(10 d and 16 d)in the middle and late grain filling period,with three replicates per sample at each time point.A total of 12 samples were sequenced and analyzed.[Result]There were 1326 differentially expressed genes(DEGs)in NJ28 and JTD at 10 days of filling,including 986 up-regulated DEGs and 340 down-regulated DEGs.At 16 days,there were 1158 DEGs,including 384 up-regulated DEGs and 786 downregulated DEGs.A total of 689 DEGs were co-changed on day 10 and day 16,including 435 up-regulated DEGs and 254 down-regulated DEGs.GO function and KEGG enrichment analysis showed that DEGs were mainly involved in starch metabolism and fatty acid metabolism,such asα-amylase,β-amylase,α-glucosidase,β-glucosidase,isoamylase,fatty acid elongation and degradation related enzymes.qRT-PCR was used to verify the three genes,and it was found that their mRNA expression trends were consistent with the expression trends in transcriptome analysis.Using GC-MS,36 fatty acids were quantified and seven fatty acids,including oleic acid,were found to be higher in the highly resistant starch varieties.[Conclusion]Candidate genes and important fatty acids that may be involved in the synthesis of resistant starch are screened,which provides research directions and molecular basis for further understanding RS synthesis in rice grain and its relationship with non-starch fatty acids.This study provides theoretical basis for the preparation of starch foods with enzyme resistance structure and low glycemic index.

关 键 词：水稻 抗性淀粉 灌浆时期 转录组学测序 

分 类 号：S511.032[农业科学—作物学]