普通小麦显性Kr1和隐性kr1基因的分子结构差异  

The Differences of Molecular Structure of Dominant Kr1 and Recessive kr1 Gene in Common Wheat

作　　者：蔡华[1] 赵维萍[1] 许柱[1] 江伟[1] 姚运涛[1] 赵怡然[1] 

机构地区：[1]滁州学院生物与食品工程学院,安徽滁州239000

出　　处：《核农学报》2016年第5期841-849,共9页Journal of Nuclear Agricultural Sciences

基　　金：安徽省自然科学基金(1308085MC34);国家重点实验室开放基金(ZW2010002);公益性行业(农业)科研专项(201303039);安徽省高校省级质量工程项目(2012gkk040)

摘　　要：Kr1基因是小麦远缘杂交不亲和的主效基因。为探究Kr1基因的特性,根据已公布的Kr1基因c DNA部分序列,采用染色体步移(Genome Walking)和c DNA末端快速扩增技术(rapid amplification of c DNA ends,RACE)克隆小麦显性Kr1基因和隐性kr1基因,并进行序列分析。结果表明,小麦Kr1基因全长4 006 bp,含有4个外显子和3个内含子,ORF全长1 671 bp,编码557个氨基酸,可形成一条完整肽链,有基因活性,Kr1蛋白三级结构与植物S位点受体激酶具有较高的相似性。kr1基因全长3 945bp,第3、第4外显子中因含有大量终止密码子,不能通读,表明kr1基因无基因活性。同时对小麦×黑麦、小麦×球茎大麦、小麦×玉米等不同远缘杂交系统的亲和性差异进行探讨,认为Kr1基因在小麦×玉米中失活可能与玉米转座子的插入有关。本研究结果为进一步阐明Kr1基因的功能及其作用机制奠定了基础。Kr1 gene is the dominant gene for distant hybridization incompatibility in wheat. In order to analyze its molecular character,the full-length sequences of the dominant and recessive Kr1 genes have been obtained by using Genome Walking and RACE PCR approaches based on its published partial c DNA sequences. The results show that,the Kr1 gene（ 4 006bp） contains a complete open reading frame（ 1 671bp） encoding 557 amino acid that could produce a complete peptide,which indicates the Kr1 gene is active. The protein tertiary structure of Kr1 is highly similar to S site receptor kinase in plants. The kr1 gene（ 3 945bp） contains a incomplete open reading frame with lots of termination codons in the 3-（rd）and 4-（th）exons,the read-through transcript cannot form,which indicates the kr1 gene is inactive. In addition,the difference of compatibility in wheat × rye,wheat × bulbous barley and wheat × maize was discussed in this paper,and the inactivation of Kr1 gene in wheat × maize is considered to be related to the maize transposon insertion.These results laid a foundation for further illustrating the function and working mechanism of Kr1 gene.

关 键 词：小麦 Kr1基因 远缘杂交不亲和 染色体步移 CDNA末端快速扩增技术 

分 类 号：S512.1[农业科学—作物学]