MOLECULAR GENETICS OF MUTATIONAL VARIATION IN MITOCHONDRIAL DNA OF DROSOPHILA

果蝇线粒体DNA突变变异的分子遗传学

• 批准号: 6395906
• 负责人: GREG S SPICER
• 金额: $ 12.7万
• 依托单位: SAN FRANCISCO STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-01-01 至 2000-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6395906
• 关键词: Drosophilidae; animal genetic material tag; biochemical evolution; gene mutation; genetic polymorphism; mitochondrial DNA; molecular genetics; natural selections; nucleic acid sequence; polymerase chain reaction; population genetics; species difference; statistics /biometry; systematic biology

The mitochondrion in eukaryotes is the organelle responsible for cellular respiration, and is unique among animal organelles in that it possess its own DNA coding genome. In the fruitfly genus Drosophila, as in humans, this genome consists of a circular molecule about 16 Kb in size, which is maternally inherited and non-recombining. It has been noted that several human diseases appear to be related to mutational aberrations in the mitochondrial DNA genome but, our understanding of the normal mutational processes occurring in mtDNA are poorly understood. Consequently, knowledge concerning the usual mutational process in a model system, such as Drosophila, would be of great interest. To understand the mutational variation found in Drosophila, sequence variation at eight protein coding mitochondrial genes within natural populations and among different species will be examined to determine the factors influencing the levels of variation. This will be accomplished by testing the evidence in two separate ways: (1) By examining whether sequence variation observed within populations of Drosophila is due to the accumulation of neutral mutations, or the result of mutational substitutions that are maintained by natural selection. This will be tested by using population genetic models based on neutral theory and coalescent theory. (2) By examining the factors affecting sequence variation in these genes among different species of Drosophila, which will be tested by using comparative phylogenetic tree methods.

真核生物中的线粒体是负责细胞 呼吸作用，在动物细胞器中是独一无二的，因为它拥有 拥有DNA编码基因组。在果蝇属中，就像人类一样， 这个基因组由一个约16kb大小的环状分子组成，它是 母系遗传和非重组。已经注意到，有几个 人类疾病似乎与基因突变有关。 但是，线粒体DNA基因组，我们对正常突变的理解 线粒体DNA中发生的过程知之甚少。因此， 关于模型系统中通常的突变过程的知识，如 作为果蝇，会引起人们极大的兴趣。 为了了解在果蝇中发现的突变变异，序列 8种编码线粒体基因的蛋白质在自然界中的变异 将对种群和不同物种之间进行检查，以确定 影响变异水平的因素。这将通过以下方式实现 以两种不同的方式检验证据：(1)检查是否 在果蝇种群内观察到的序列差异是由于 中性突变的积累，或突变的结果 由自然选择维持的替换。这将是 使用基于中性理论的种群遗传模型和 结合论。(2)通过考察影响排序的因素 这些基因在不同种类的果蝇之间的差异，这将是 采用比较系统发育树方法进行检验。