o2突变引起糯玉米籽粒淀粉积累差异研究
Analysis of differential accumulation of starch in waxy maize grain caused by the o2 mutation gene
韩洁楠 1张泽 2刘晓丽 1李冉 1上官小川 2周婷芳 2潘越 1郝转芳 1翁建峰 1雍洪军 1周志强 1徐晶宇 3李新海 2李明顺1
作者信息
- 1. 中国农业科学院作物科学研究所, 北京 100081
- 2. 中国农业科学院作物科学研究所, 北京 100081;黑龙江八一农垦大学农学院, 黑龙江大庆 163319
- 3. 黑龙江八一农垦大学农学院, 黑龙江大庆 163319
- 折叠
摘要
糯玉米是主要鲜食玉米类型,opaque2(o2)基因导入可增加籽粒赖氨酸含量,但同时引起籽粒皱缩、淀粉含量下降等,限制了其育种应用.为发掘优良糯玉米受体,以籽粒饱满圆型o2 近等基因系(o2-NIL)糯 2/wx1wx1o2o2 和皱缩型黄糯 2/wx1wx1o2o2 为研究材料,通过对鲜食期、成熟期的百粒重和籽粒成分测定,发现淀粉和可溶性糖含量不同可能是导致 2 份糯玉米o2-NILs表型差异的主要原因.利用实时荧光定量PCR技术分析,发现授粉后 10～24 d两糯玉米o2-NILs中 6 个淀粉合成基因动态表达模式不同,其中Sh1、Sh2、SSⅢa和SBEⅡb差异较大.分析胚乳转录组数据,发现两糯玉米o2-NILs中 24 个海藻糖和糖基水解酶编码基因和 48 个o2 胚乳修饰基因变化不同,以上结果表明淀粉合成关键基因前期表达量高,后期与对照无差异,且糖代谢基因表达变化有利于淀粉合成可能是糯2/wx1wx1o2o2 淀粉含量和百粒重不受 o2 突变影响,籽粒性状明显优于黄糯 2/wx1wx1o2o2 的重要原因,同时多个胚乳修饰基因的差异表达可能与该结果直接相关.本研究结果可为o2 突变体在玉米育种中的应用提供重要参考.
Abstract
The primary variety of fresh maize known as waxy maize undergoes a transformation with the introduction of the opaque2(o2)mutant gene,resulting in an increased lysine content,thus improving the grain's nutritional composition.Yet,the o2 mutation brings about desirable agronomic traits such as wrinkle formation and a decrease in starch content,which restrict its use in breeding applications.To explore the high performing waxy maize o2 receptors,we capitalized on the use of o2 near-isogenic line(o2-NIL),specifically the plump and round grain type Nuo 2/wx1wx1o2o2 and its wrinkled counterpart,Huang-nuo2/wx1wx1o2o2.Measurements of 100-grain weight and grain composition at the fresh ear and mature stages showed that there was difference in starch and soluble sugar content,which might be the primary cause of kernel phenotype variation between the two waxy maize o2-NILs.Genetic analysis of starch synthesis in the two o2-NILs was performed using qRT-PCR technique re-vealed that six gene-regulated trends fluctuated between 10 and 24 days after pollination,among which Sh1,Sh2,SSⅢa,and SBEⅡb genes were significant differences.Endosperm transcriptomes indicated that 24 genes encoding trehalose and glycosyl hydrolases and 48 genes involved in endosperm modification exhibited distinct changes between the two o2-NILs.There was no detectable alteration in the 100-grain weight or the starch content of Nuo 2/wx1wx1o2o2,which may well be tied to the early high-level expression of the primary starch synthesis gene,leaving later stages unchanged compared with the control.Furthermore,the shifts in the expression of sugar metabolism genes was beneficial to starch synthesis,which may be an important reason why starch content and 100-kernel weight of Nuo 2/wx1wx1o2o2 were unaffected by the o2 mutation,and grain traits were signifi-cantly better than the superior grain traits compared with Huangnuo 2/wx1wx1o2o2.These results may be directly related to the differential expression of multiple endosperm modifying genes.The results of this study can provide important reference for the future utilization of o2 mutants in maize breeding.
关键词
糯玉米/糯2/wx1wx1o2o2/黄糯2/wx1wx1o2o2/籽粒饱满度/淀粉/糖代谢/差异基因Key words
waxy maize/Nuo 2/wx1wx1o2o2/Huangnuo 2/wx1wx1o2o2/kernel fullness degree/starch/sucrose metabolism/different expression genes引用本文复制引用
基金项目
国家重点研发计划(2021YFD1201004)
现代农业产业技术体系建设专项(玉米)
现代农业产业技术体系建设专项(CARS-02)
出版年
2024
国家科技期刊平台
NSTL
万方数据