Agrobacterium Regulation of Plant Responses

农杆菌对植物反应的调节

• 批准号: 0222335
• 负责人: Eugene Nester
• 金额: --
• 依托单位: University of Washington
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-09-01 至 2007-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0222335&HistoricalAwards=false
• 关键词: Agrobacterium; Regulation; Plant; Responses

Genetic transformation of plants by Agrobacterium tumefaciens is the only documented case of gene transfer to eukaryotes in nature. As such, this system has attracted a great deal of attention from a broad scientific audience concerned with its biology, its use in unraveling complex problems in plant genetics and its biotechnological applications in creating transgenic plants. Recent findings have broadened the possible applications of Agrobacterium as a vector for the transfer of DNA to fungi, oomycetes and animals. Using cDNA-AFLP analysis, our laboratory demonstrated that Agrobacterium and E.coli alter the expression of plant defense and stress response genes of Ageratum conyzoides cells in culture. However, Agrobacterium also induced a gene encoding a nodulin-like protein which was not altered by E.coli suggesting that Agrobacterium can induce specific host genes. The project expands on these observations and will study global expression in cell cultures of the model plant Arabidopsis thaliana using high density microarray technology. Cell cultures of Arabidopsis will be cocultivated for 24 hours with E.coli as well as transfer proficient Agrobacterium and mutants blocked at different major steps in the infection process. Comparing the genes expressed using microarrays will reveal these genes that are specifically altered by Agrobacterium. Comparing the alterations in gene expression induced by the transfer proficient strain with the mutants will begin to identify genetic factors responsible for these alterations. The effects observed using the first set of mutants will be further refined by using additional mutants blocked at single steps in the infection process. The results of these experiments should provide insight into the unique genetic factors of the near symbiont Agrobacterium which provides its ability to overcome host defenses and ultimately lead to the transfer of DNA to a remarkably wide range of plants and other eukaryotic cells.

农杆菌介导的植物遗传转化是自然界中唯一有记载的基因转移到真核生物中的情况。因此，这个系统已经吸引了大量的关注，从一个广泛的科学观众关心它的生物学，它在解开复杂的问题，在植物遗传学和它的生物技术应用在创建转基因植物。最近的发现拓宽了农杆菌作为将DNA转移到真菌、卵菌和动物中的载体的可能应用。本实验室利用cDNA-AFLP技术研究了农杆菌和大肠杆菌对胜红蓟细胞中植物防御和胁迫反应基因表达的影响。然而，农杆菌还诱导编码结瘤蛋白样蛋白的基因，该基因不被大肠杆菌改变，这表明农杆菌可以诱导特异性宿主基因。该项目扩展了这些观察，并将研究全球表达的模式植物拟南芥细胞培养物中使用高密度微阵列技术。将拟南芥的细胞培养物与大肠杆菌以及在感染过程中的不同主要步骤阻断的转移熟练的农杆菌和突变体共培养24小时。比较使用微阵列表达的基因将揭示这些基因被农杆菌特异性改变。将转移熟练菌株诱导的基因表达变化与突变体进行比较将开始鉴定导致这些变化的遗传因素。使用第一组突变体观察到的效果将通过使用在感染过程中的单个步骤阻断的额外突变体来进一步细化。这些实验的结果应该提供洞察的独特的遗传因子的近共生农杆菌提供其能力，克服宿主防御，并最终导致DNA转移到一个非常广泛的植物和其他真核细胞。