水稻雄性不育突变体gamyb5的鉴定与基因定位  

Identification and Gene Mapping of Male Sterile Mutant gamyb5 in Rice

作　　者：杨正福 张迎信[1] 孙廉平[1,2] 张沛沛[1] 轩丹丹 刘嶺 胡霞[1] 李紫荷 占小登[1] 吴玮勋[1] 曹立勇[1] 程式华[1] 

机构地区：[1]中国水稻研究所/国家水稻改良中心/浙江省超级稻研究重点实验室,杭州311401 [2]沈阳农业大学农学院,沈阳110866 [3]河南农业大学农学院,郑州450002

出　　处：《中国水稻科学》2016年第2期143-151,共9页Chinese Journal of Rice Science

基　　金：农业部农业公益性行业科技专项(20140302,20150308);国家转基因重大专项(2014ZX08001-002);浙江省自然科学基金资助项目(Q13C130009);中国农业科学院创新工程超级稻育种创新团队;水稻杂种优势机理研究创新团队项目(CAAS-ASTIP-2013-CNRRI);国家自然科学基金资助项目(31501290)

摘　　要：在60 Co-γ射线辐射诱变籼稻中恢8015的突变体库内发现了一个无花粉型雄性不育突变体gamyb5。gamyb5的株型、株高、分蘖数等农艺性状与野生型中恢8015无差异,而其花药细长且呈白色半透明状,花药中无花粉粒。花药半薄切片观察结果表明,gamyb5的小孢子母细胞减数分裂异常,没有形成正常的四分体和小孢子,并且绒毡层异常伸长,细胞程序性死亡延迟。对以gamyb5为母本,与野生型中恢8015和广亲和粳稻品种02428分别配制的杂交组合遗传分析表明,gamyb5突变性状受一个隐性核基因控制。利用gamyb5和02428杂交的F2定位群体,最终将突变基因精细定位于第1染色体长臂的ZF-29和ZF-31两个标记之间,物理距离约16.9kb。对该区域内2个完整的开放阅读框测序分析发现,编码受赤霉素诱导的MYB转录因子基因LOC_Os01g0812000的第2外显子存在8个碱基的缺失,导致翻译提前终止。qRT-PCR检测到影响花药发育的调控因子UDT1、TDR、CYP703A3和CYP704B2的表达量在突变体中比野生型中极显著降低。进一步证明GAMYB在花药减数分裂和绒毡层细胞程序性死亡过程中起关键作用。The gamyb5,apollen-free male sterile mutant was identified from the mutant library of 60 Co-γ-treated indica cultivar Zhonghui 8015.There was no significant difference in agronomic traits such as plant type,plant height and tiller number between gamyb5 and the wild-type.But gamyb5 exhibited slender and white anthers without mature pollen grains.Observation results of anther cross-sections exhibited that the microspore mother cells failed to form functional tetrads and microspores in gamyb5.Moreover,tapetal cells of gamyb5 abnormally enlarged and the tapetum programmed cell death(PCD)was delayed.gamyb5,as the pollen acceptor,was crossed with the wild type Zhonghui8015 and a japonica cultivar 02428,respectively.Genetic analysis of all hybridization populations indicated that gamyb5 was controlled by a single recessive nuclear gene which was mapped on the long arm of chromosome 1.With developed SSR,Indel markers and F2 mapping population of gamyb5/02428,the gene was fine mapped to a region of16-kb on the long arm of chromosome 1between markers ZF-29 and ZF-31.Sequence analysis of the two open reading frames in this region revealed that the LOC_Os01g0812000,which encodes a gibberellin-induced MYB transcription factor,had an 8nucleotides bases deletion in the second extron probably responsible for the male sterility phenotype.Additionally,real-time fluorescent quantitative PCR analysis showed that the expression level of the important regulators UDT1,TDR,CYP703A3 and CYP704B2 in anther decreased significantly in gamyb5.Together,these results suggest GAMYB plays key roles in anther meiosis and tapetum PCD.

关 键 词：水稻 雄性不育 基因定位 gamyb5 

分 类 号：S511[农业科学—作物学]