水稻叶片水势的QTL定位与候选基因分析  

QTL Mapping and Candidate Gene Analysis on Rice Leaf Water Potential

作　　者：潘晨阳 张月 林晗[1] 陈芊羽 杨凯如 姜嘉骥 李梦佳 芦涛 王珂欣 路梅[1] 王盛 叶涵斐 饶玉春[1] 胡海涛[1] Chenyang Pan;Yue Zhang;Han Lin;Qianyu Chen;Kairu Yang;Jiaji Jiang;Mengjia Li;Tao Lu;Kexin Wang;Mei Lu;Sheng Wang;Hanfei Ye;Yuchun Rao;Haitao Hu(College of Chemistry and Life Sciences,Zhejiang Normal University,Jinhua 321004,China)

机构地区：[1]浙江师范大学化学与生命科学学院,金华321004

出　　处：《植物学报》2021年第3期275-283,共9页Chinese Bulletin of Botany

基　　金：广西水稻遗传育种重点实验室开放基金(No.2018-15-Z06-KF12);中国水稻生物学国家重点实验室研究基金(No.20200102);浙江省教育厅项目(No.Y202045759);2020年国家级大学生创新创业训练计划(No.202010345067);2021年国家级大学生创新创业训练计划(No.202110345010)。

摘　　要：为探究叶片水势(LWP)相关基因在水稻(Oryzasativa)抗旱中的作用及其遗传机制,以热研2号(Nekken2)和华占(HZ)为亲本以及构建的120个重组自交系(RILs)群体为实验材料,对水稻分蘖期叶片水势进行检测,并利用前期基于高通量测序构建的分子遗传连锁图谱进行数量性状基因座(QTL)分析。结果表明,共检测到5个与水稻分蘖期叶片水势相关的QTLs,分别位于第2、3、4、11和12号染色体上,LOD值均达2.5以上,其中位于4号染色体物理距离24066261–30847136 bp内QTL的LOD值高达5.15。对这些QTL区间内与水势相关的候选基因进行定量分析,发现LOCOs02g56630、LOCOs02g57720、LOCOs02g57580、LOCOs04g43730、LOCOs04g46490、LOCOs04g44570和LOCOs04g44060这7个基因在双亲间表达量差异显著。位于4号染色体QTL区间内LOCOs04g46490基因的表达在两亲本间存在显著差异。对基因LOCOs04g46490进行测序分析,发现该基因在两亲本间共存在6处差异,从而导致氨基酸序列的改变。通过QTL挖掘及相关基因表达分析,发现这些基因与水稻叶片水势调控相关,可能间接影响水稻的抗旱性。检测到的QTL位点对水势相关基因精细定位和克隆具有重要参考价值,有助于进一步理解水稻叶片水势的遗传基础,并为培育耐旱水稻新品种提供有利的基因资源。To reveal the role and genetic mechanism of genes related to leaf water potential(LWP)in rice drought resistance,the 120 recombinant inbred lines(RILs)populations derived from the cross of Nekken2 and HZ as well as the two parents were chosen as the experiment materials in this study.After testing and analyzing the leaf water potential at tillering stage,quantitative trait loci(QTL)were detected based on the molecular linkage map of these populations constructed by using high-throughput sequencing in the early stage.The experimental results showed that 5 QTLs related to leaf water potential at tillering stage were located on chromosome 2,3,4,11 and 12,respectively,with LOD(likelihood of odd)value all above 2.5,one of which located on chromosome 4 with physical distance between 24066261 and 30847136 bp showed the highest LOD value of 5.15.Through quantitative analysis of these candidate genes relevant to leaf water potential within the QTL regions,7 genes,LOCOs02 g56630,LOCOs02 g57720,LOCOs02 g57580,LOC Os04 g43730,LOCOs04 g46490,LOCOs04 g44570,LOCOs04 g44060,were identified to have different expression levels between the two parents.LOCOs04 g46490,which located within the QTL region on chromosome 4,showed significant difference in gene expression and 6 differences at DNA sequences and changes at amino acids between two parents.By QTL mining and quantitative analysis of related genes,we discovered that these genes were associated with the regulation of leaf water potential,which may indirectly affect the drought resistance of rice.The detected QTL loci have important reference value for QTL fine mapping and genes cloning associated with drought tolerance,thus facilitating our understanding of the genetic basis of rice leaf water potential,and providing genetic resources for developing new drought-tolerant rice cultivars.

关 键 词：水稻 叶片水势 抗旱 遗传图谱 QTL定位 

分 类 号：S511[农业科学—作物学]