Mitochondrial DNA Recombination Proteins in Arabidopsis

拟南芥线粒体 DNA 重组蛋白

• 批准号: 6556385
• 负责人: BRENT L NIELSEN
• 金额: $ 14.07万
• 依托单位: BRIGHAM YOUNG UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-02-01 至 2005-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6556385
• 关键词: Arabidopsis; SDS polyacrylamide gel electrophoresis; antisense nucleic acid; apoptosis; electron microscopy; gel mobility shift assay; gene expression; gene rearrangement; genetic recombination; genetic regulation; genetically modified plants; mitochondria; mitochondrial DNA; northern blottings; plant proteins; protein purification; protein structure; western blottings

DESCRIPTION (provided by applicant): Mitochondria are the site of the essential process of respiration in eukaryotic cells, and contain DNA separate from the nucleus, which encodes only some of the genes needed for mitochondrial function. Mitochondrial gene sequence mutations and deletions have been linked with various human diseases, including cardiomyopathy, neuropathy and various aging disorders. In plants, mitochondrial genome alterations are associated with cytoplasmic male sterility, which results in abortive pollen production. Our long-term goals are to understand the relationship between mitochondrial genome recombination and genome maintenance and repair, and resulting effects on mitochondrial function. We have chosen Arabidopsis thaliana as a model system for these studies, as the complete genome (nuclear, mitochondrial and chloroplast) is now available, propagation of this plant is easy and generation time is short, and genetic studies are possible with this species. Our immediate goals are to identify and characterize genes for mitochondria-targeted recombination proteins in A. thaliana, and characterize the gene products. Homologues of the E. coli rec A and ssb genes, which have mitochondrial targeting sequences, will initially be studied. We have obtained clones of these genes, and their expression will be analyzed in various tissues and ages of plants by northern and western blot analysis to determine if there are spatial or developmental differences in expression of these genes. The effect of over expression of the recA or ssb genes, driven either by global or tissue-specific strong promoters, will be determined in transgenic Arabidopsis plants. Disruption of the endogenous genes by gene knockout or antisense technology will also be examined to determine if mitochondrial DNA recombination is essential for proper I growth and development, and if gene disruption leads to greater susceptibility to DNA damaging agents. Additional Arabidopsis genes with predicted mitochondrial targeting sequences for proteins involved in recombination will be identified and like wise characterized. Our findings will provide greater insights into processes affecting mitochondrial genome integrity, which may be extended to mitochondria from other eukaryotes.

描述（由申请人提供）：线粒体是真核细胞中呼吸的基本过程的位点，并且含有与细胞核分离的DNA，其仅编码线粒体功能所需的一些基因。线粒体基因序列突变和缺失与各种人类疾病有关，包括心肌病、神经病和各种衰老疾病。在植物中，线粒体基因组的改变与细胞质雄性不育有关，这导致花粉产生败育。我们的长期目标是了解线粒体基因组重组和基因组维护和修复之间的关系，以及对线粒体功能的影响。我们选择拟南芥作为这些研究的模型系统，因为完整的基因组（核，线粒体和叶绿体）现在是可用的，这种植物的繁殖很容易，世代时间短，遗传研究是可能的。我们的近期目标是鉴定和表征A. thaliana，并表征基因产物。E.大肠杆菌rec A和ssb基因，其中有线粒体靶向序列，将首先进行研究。我们已经获得了这些基因的克隆，并将通过北方和western印迹分析来分析它们在植物的各种组织和年龄中的表达，以确定这些基因的表达是否存在空间或发育差异。将在转基因拟南芥植物中确定由全局或组织特异性强启动子驱动的recA或ssb基因的过表达的影响。通过基因敲除或反义技术破坏内源性基因也将进行检查，以确定线粒体DNA重组是否对正常的生长和发育至关重要，以及基因破坏是否导致对DNA损伤剂的更大易感性。 将鉴定具有参与重组的蛋白质的预测线粒体靶向序列的另外的拟南芥基因，并类似地表征。我们的研究结果将为影响线粒体基因组完整性的过程提供更深入的见解，这可能会扩展到其他真核生物的线粒体。