水稻穗异常突变体tutou4的鉴定及基因定位  

Identification and Fine Mapping of a Panicle Aberrant Mutant tutou4 in Rice(Oryza sativa L.)

作　　者：宋远辉[1] 花芹 林泉祥 郑思怡 欧阳晨林 杨晔 孙家猛 陈庆全[1] 李金才[1] 张海涛[1] SONG Yuan-hui;HUA Qin;LIN Quan-xiang;ZHENG Si-yi;OUYANG Chen-lin;YANG Ye;SUN Jia-meng;CHEN Qing-quan;LI Jin-cai;ZHANG Hai-tao(College of Agronomy,Anhui Agricultural University,Hefei 230036)

机构地区：[1]安徽农业大学农学院,合肥230036

出　　处：《植物遗传资源学报》2021年第5期1304-1313,共10页Journal of Plant Genetic Resources

基　　金：国家自然科学基金项目(31871603,31201205);国家留学基金委项目(201708340008);安徽省科技厅项目(KJ2017A143,gxfxZD2016022);安徽省科技重大专项(1803071176)~~。

摘　　要：水稻穗异常退化现象在水稻的生长发育过程中经常发生。穗部退化可引起穗长、枝梗数、每穗粒数和结实率下降,影响单株产量。穗退化性状因其遗传基础复杂、受环境和生理因素影响较大,其分子机制及其遗传网络仍知之甚少。tutou4是一个来自于组织培养的穗异常退化突变体,该突变体表现为穗部部分颖花退化,每穗粒数和枝梗数减少,单株产量降低。遗传分析表明,该性状由一对隐性核基因控制,通过图位克隆的方法最终将候选基因定位在水稻第8染色体短臂端Os8-3-2和Os8-3-3之间,遗传距离为39.09 kb的范围内。该区间包括3个编码基因,通过测序发现tutou4突变体中基因LOCOs08g06480的起始密码子上游有4325 bp的片段缺失,且最后一个外显子(7538 bp)上碱基A被替换成碱基G,但氨基酸未改变。荧光定量PCR的结果表明,该基因在突变体中表达量显著下降。因此,tutou4穗异常性状可能是由Tutou4启动子缺失或外显子碱基替换造成的基因表达量降低引起的表型突变。Tutou4为已报道基因OsLIS-L1/OsREL2/ASP1的等位基因。Tutou4穗发育异常的表型为研究穗部发育的分子机制提供了新的材料基础。Aberrant degeneration of panicle(ADP)usually occurs during the reproductive growth in rice.It causes yield loss due to the reductions of panicle length,branch number,grain number per panicle and seed setting.However,the molecular mechanism of ADP remains largely unknown since the complicated genetic basis and sensitivity to environmental and physiologic factors.tutou4 is a panicle degeneration mutant derived from tissue culture,and shows abnormal panicle,reduction of grain number and branch number per panicle,as well as single plant yield.Genetic analysis showed that the ADP trait was controlled by a pair of recessive nuclear gene.The candidate region was finally mapped to the short arm of chromosome 8,flanked by both Indel markers Os8-3-2 and Os8-3-3,with an interval of 39.09 kb,which contained three encoding genes.The sequencing results showed a 4325 bp deletion in the promoter region and one base alternation(7538 bp,A→G,synonymous)of the gene LOCOs08 g06480,which was designated as OsLIS-L1/OsREL2/ASP1.Real-time PCR analysis revealed the reduction of this gene expression in mutant to that of the wild type.Considering the expression level decreased in the tutou4,this mutant will be an useful germplasm in the study of abnormal panicle degeneration.

关 键 词：水稻 穗异常 表型分析 花粉败育 图位克隆 

分 类 号：S511[农业科学—作物学]