XCRK基因在水稻与细菌性条斑病菌互作中的功能解析

(1.厦门大学 生命科学学院,厦门市植物遗传重点实验室,福建 厦门 361102; 2.湖南理工学院化学化工学院,湖南 岳阳 414006)

细菌性条斑病; 超量表达载体; RNAi表达载体; 转基因水稻

Functional Analysis of XCRK Gene in the Interaction Between Rice and Bacterial Leaf Streak Strain
ZHANG Yuxia1,2,CUI Yuchao1,LI Yan1,ZHOU Dan1,CHEN Liang1*

(1.Xiamen Key Laboratory for Plant Genetics,School of Life Sciences,Xiamen University,Xiamen 361102,China; 2.School of Chemistry and Chemical Engineering,Hunan Institute of Science and Technology,Yueyang 414006,China)

bacterial leaf streak(BLS); over-expression vector; RNAi expression vector; transgenic rice

DOI: 10.6043/j.issn.0438-0479.201706006

备注

XCRK(Xoc-associated receptor-like kinase)基因是对水稻细菌性条斑病(bacterial leaf streak,BLS)致病菌侵染应答的差异蛋白质组学研究中发现的一个拟抗病基因.生物信息学分析显示该基因位于水稻的1号染色体上,编码一个含有322个氨基酸的蛋白激酶.组织表达分析显示XCRK基因在根、茎、叶、花序等组织中均有表达,且其表达受高盐、H2O2和脱落酸(ABA)的诱导.为了探究XCRK基因在水稻BLS中的作用,通过PCR扩增XCRK基因编码区,构建超量表达载体,并转化水稻愈伤组织获得了超量表达XCRK基因的转基因水稻植株; 同时构建了RNA干扰(RNAi)表达载体,并获得了抑制表达XCRK基因的转基因水稻植株.对T1代转基因植株进行了BLS抗性分析,结果显示:超量表达XCRK基因明显增强了转基因水稻对BLS致病菌的抗性; 相反地,抑制表达XCRK基因的转基因水稻对BLS致病菌的敏感性则略有增强.综上结果表明XCRK基因正调控水稻对BLS的抗性,这为进一步研究该基因的作用机制提供了理论依据.

XCRK is a candidate gene for disease resistance that has been detected from rice genome based on the study of differentially expressed proteins from rice leaves in response to bacterial leaf streak(BLS).Bioinformatic analysis shows that XCRK gene is located on chromosome 1,encoding a 322 amino acid protein kinase.The expression of XCRK gene is induced by high salt,H2O2 and ABA.Through qRT-PCR and promoter-GUS assays,we analyzed the tissue-specific expression of XCRK gene.The results showed that XCRK gene was widely expressed in multiple rice tissues,including roots,stems,leaves and inflorescences.To explore the role of XCRK protein in rice resistance to BLS,we amplified the gene coding region by PCR,constructed gene over-expression vector,and transformed into rice callus.Meanwhile,RNA interference(RNAi)expression vector was constructed and rice transgenic lines were obtained.The research on BLS resistance in the T1 generation of transgenic plants indicated that over-expressing XCRK gene significantly improved the disease resistance of the transgenic plants to BLS,while suppressing its expression slightly enhanced the susceptibility of the transgenic to BLS,indicating that the XCRK gene positively regulated resistance of rice to BLS.These results establish the foundation for further study of the precise functional mechanism of the XCRK gene.