病原菌TAL效应子与寄主靶基因相互识别的分子密码

Molecular recognition code between pathogenic bacterial TAL-effectors and host target genes: a review

摘要:

黄单胞杆菌属TAL效应子类蛋白作为病原菌的毒性因子或无毒因子，能够与寄主靶基因DNA的启动子进行特异性识别，调控寄主的基因表达，引起致病或抗病反应。TAL效应子类蛋白识别靶基因DNA的模式，是2个氨基酸决定1个核苷酸的识别。这种新型的蛋白质-DNA互作方式有可能在基因治疗、植物抗病基因发掘、广谱抗病基因构建等生物医学工程和农业工程方面得到广泛应用。文中综述了TAL效应子类蛋白的发现及功能，TAL效应子与寄主靶基因识别的专一性及分子密码，并对该分子密码当前的应用现状及前景进行了讨论和展望。

关键词:TAL效应子，分子识别密码，蛋白质-DNA互作，基因治疗，抗病育种

Abstract:

As the pathogenic bacterial virulence and avirulence factors, transcription activator like (TAL) effectors of Xanthomonas can resulted in the host diseases or resistance responses. TAL effectors can specifically bind the target DNA of host plant with a novel protein-DNA binding pattern in which two amino acids recognize one nucleotide. The complexities of TAL-DNA binding have the feasibility in use of gene therapy through homologous recombination and site-specific mutation. By using the molecular recognition code between TAL-effectors and host target genes, we can exploit both the susceptible and resistance genes; broad spectrum resistance induced by multiple TAL effectors could also be manipulated. Deeper insight in the area of protein-DNA binding mechanism will benefit the application in the biomedical engineering and agricultural engineering. This article reviews the findings and functions of TAL effectors, the binding specificity and recognition code between TAL-effectors and host target genes. The possible applications and future prospects of the molecular recognition code have been discussed.

Key words:TAL effector, molecular recognition code, protein-DNA binding, gene therapy, disease resistance breeding