Piecing Together the Agrobacterium Type IV Secretion System Involved In DNA Transfer to Plants

拼凑参与 DNA 向植物转移的 IV 型农杆菌分泌系统

• 批准号: 0343566
• 负责人: Patricia Zambryski
• 金额: $ 80万
• 依托单位: University of California-Berkeley
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-01-15 至 2009-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0343566&HistoricalAwards=false
• 关键词: Piecing; Together; Agrobacterium; Type; IV

Agrobacterium is a soil bacterium with the natural ability to transfer DNA from the bacterium into the plant cell where it integrates into the plant's genome. Scientists co-opt this ability, allowing the genetic engineering of plants, with DNA of interest. While many steps in the transformation pathway have been elucidated, a major question remains. How is DNA transported out of the bacterium and into the plant? The Agrobacterium DNA transporter belongs to a growing class of evolutionarily conserved transporters, called type IV secretion systems (T4SS). T4SS are involved in i) bacterial mating, and ii) protein toxin export when pathogenic bacteria infect plant and animal hosts. The Agrobacterium T4SS contains 12 proteins; the long-term goal is to understand how these 12 proteins establish T4SS architecture and function. The research will first determine which proteins interact with each other, and thus are in close contact. This approach defines which pairs of proteins reside at the entrance, versus the exterior or interior of the channel, and leads to models for the assembly of theT4SS apparatus. Second, genetic strategies will confirm these predicted models. Finally, the research will determine the 3D structure of individual T4SS proteins using crystallography and bioinformatics. Thus, these studies will provide an exact structure for the T4SS. This basic research will impact society in medicine and agriculture. Structural information on the T4SS is essential to allow the development of disease treatment therapies that disrupt transporter function in bacteria that transfer toxins to susceptible hosts. Moreover, an understanding of T4SS may allow modification of the transporter in Agrobacterium to increase its effectiveness for plant transformation.

农杆菌是一种土壤细菌，具有将细菌的 DNA 转移到植物细胞中的天然能力，并在植物细胞中整合到植物的基因组中。科学家们利用这种能力，利用感兴趣的DNA对植物进行基因工程。尽管已经阐明了转型途径中的许多步骤，但仍然存在一个主要问题。 DNA 是如何从细菌中转运到植物中的？农杆菌 DNA 转运蛋白属于不断增长的进化保守转运蛋白类别，称为 IV 型分泌系统 (T4SS)。当病原菌感染植物和动物宿主时，T4SS 参与 i) 细菌交配，以及 ii) 蛋白质毒素输出。农杆菌 T4SS 含有 12 种蛋白质；长期目标是了解这 12 种蛋白质如何建立 T4SS 结构和功能。该研究将首先确定哪些蛋白质彼此相互作用，从而保持密切联系。这种方法定义了哪些蛋白质对位于入口处，哪些蛋白质对位于通道的外部或内部，并产生了 T4SS 装置的组装模型。其次，遗传策略将证实这些预测模型。最后，该研究将利用晶体学和生物信息学确定单个 T4SS 蛋白的 3D 结构。因此，这些研究将为 T4SS 提供精确的结构。这项基础研究将对医学和农业社会产生影响。 T4SS 的结构信息对于开发疾病治疗疗法至关重要，这些疗法可以破坏细菌中将毒素转移到易感宿主的转运蛋白功能。此外，对 T4SS 的了解可能允许修改农杆菌中的转运蛋白，以提高其植物转化的有效性。