基于大豆导入系群体结瘤相关性状QTL定位及基因挖掘

氮元素是植物生长所需的重要营养元素之一,生物固氮是大豆生长所需氮元素的重要来源。本实验室以绥农14为母本,野生豆ZYD00006为父本构建一套覆盖野生大豆全基因组的导入系群体。基于大豆导入系群体对结瘤数目和干重进行QTL定位,定位到3个QTL与根瘤干重相关,分布在N、M和D2这3个连锁群上,定位到5个QTL与根瘤数相关,分布在K、F、J和D2这4个连锁群上,在D2连锁群这两个性状有重叠区段(7.20-7.79Mb)。针对这个重叠区段的63个基因进行基因注释,选择到6个与共生、抗病相关的基因作为候选基因进行下一步验证。qRT-PCR分析表明根瘤菌侵染期间Glyma.17G097000基因表达模式与对照相比差异很大。Glyma.17G097000属于GmHIR基因家族,在大豆基因组中发现了11个家族成员。GmHIR家族基因结构相似性很高,基因表达有组织特异性。大豆HIR蛋白有Stomatins和Prohibitin两个结构域,能够参与离子通道调节等生理过程,与植物抗病和细胞周期有关。GmHIR基因来源于四个祖先,进化过程中是高度保守的。对GmHIR基因家族11个成员qRT-PCR检测,结果显示根瘤菌感染期间Glyma.05G029800、Glyma.09G154400和Glyma.17G097000这三个基因与对照相比表达模式差异较大。结果表明这三个基因可能在大豆共生体系建立中起着重要的作用,参与根瘤菌与大豆共生体系建立过程中的离子通道调节和免疫反应。本研究为大豆-根瘤菌共生机制研究奠定基础并提供有效候选基因。

QTLs analysis and gene mining of soybean symbiotic nodulation based on introgression lines

Nitrogen is an important nutrient for plant growth,and biological nitrogen fixation is an important source of nitrogen to soybean growth.In this study,we used Suinong14 as the recurrent parent and wild bean ZYD00006 as the male parent to construct an introgression lines covering the whole genome of wild soybean.QTL mapping of nodule number and nodule dry weight based on soybean introduced line group.Three QTLs for nodule dry weight,located on three linkage groups of N,M and D2.Five QTLs for nodule number,located on linkage groups K,F,J and D2.There are overlapping segments(7.20-7.79Mb)on D2 linkage group.Gene annotation was performed on 63 genes in this overlapping segment,and 6 genes related to symbiosis and disease resistance were se lected as candidate genes for further verification.The qRT-PCR analysis showed that the expression pattern of Gly ma.17G097000 during rhizobial infection was very different compared to the control.Glyma.17G097000 belongs to the GmHIR gene family,and 11 family members were found in the soybean genome.The structural similarity of Gm HIR family genes is very high,and genes expression is tissue-specific.Soybean HIR protein has two domains,Stomatins and Prohibitin,and can participate in physiological processes such as ion channel regulation,which are related to plant disease resistance and cell cycle.The GmHIR genes are derived from four ancestors and highly con served during evolution.The qRT-PCR analysis of 11 members of GmHIR gene family showed that the expression patterns of these three genes Glyma.05G029800,Glyma.09G154400 and Glyma.17G097000 during rhizobial infec tion were significantly different from the control.These results indicated that these three genes could have played an important role in the establishment of a soybean symbiosis system,and participated in the regulation of ion channels and immune responses during the establishment of a symbiotic system of rhizobium and soybean.This study lays the foundation for the study of soybean-rhizobia symbiosis mechanism and provides effective candidate genes.