Molecular evolution and ecological adaptation of male- and female-transmitted mtDNA genomes in bivalves

我的长期目标是了解在双壳软体动物中存在的线粒体DNA遗传的起源和维持高度不寻常的系统的因素。这一系统被称为线粒体DNA的双亲遗传(DUI)。与所有其他动物不同，许多双壳类动物拥有两个截然不同的性别相关的mtDNA谱系，而不仅仅是一个单一的、由雌性传播的mtDNA谱系。我的短期目标是测试各种假说，这些假说被用来解释与男性和女性传播的DNA基因组的发育控制和进化动力学相关的因素。这些假设包括，酒后驾车允许自然选择来改善这些贻贝的精子性能，或者这些与性别相关的基因组可能在性别决定中发挥作用。在海洋贻贝中发现的不同的雄性和雌性传递的mtDNA基因组也经历了重组，直到最近，人们还认为这种现象不会在动物的mtDNA基因组中发生。我研究这种不同寻常的线粒体DNA遗传系统的方法包括结合精子运动分析、线粒体全基因组测序分析和生物信息学/电子分析。我的研究的预期结果是促进我们对基本生物学过程的理解，主要是在双壳类中，但这种知识也将适用于其他动物群体。我的研究将促进我们对基本细胞过程的理解，并将对遗传学家、无脊椎动物生物学家和动物学家产生普遍的兴趣和价值。在双壳类性别决定领域的纯知识的进步可能在水产养殖领域和通过人工控制性别比例发展入侵淡水贻贝物种的生物控制方面有应用。我的研究对解释线粒体DNA的进化也有广泛的意义。例如，我的研究计划将为解释一种名为Cox1的特定基因的DNA序列提供必要的数据，该基因被用作“生命条形码联盟”倡议的基础。这是一项利用DNA序列数据通过一种简单、廉价的测试来识别世界上所有动物物种的尝试。随着本土海洋和淡水贻贝面临全球气候变化和入侵双壳类物种的全球运输的威胁，对这些物种的DNA条形码的正确解释将变得越来越重要。

My long-term objectives are to understand the origin and factors maintaining a highly unusual system of mitochondrial DNA inheritance present in bivalve mollusks. This system is called “doubly uniparental inheritance” (DUI) of mitochondrial DNA. Unlike all other animals, many groups of bivalves possess two distinct sex-associated mtDNA lineages rather than just a single, female-transmitted mtDNA lineage. My short-term objectives are to test various hypotheses that have been proposed to explain factors associated with the developmental controls and evolutionary dynamics of the male- and female-transmitted DNA genomes. These hypotheses include the proposal that DUI allows for natural selection to improve sperm performance in these mussels, or that these gender-associated genomes might play a role in sex determination. The distinct male and female transmitted mtDNA genomes found in marine mussels also undergo recombination, a phenomenon that was, until recently, not thought to occur in animal mtDNA genomes. My approach to studying this unusual system of mitochondrial DNA inheritance includes a combination of sperm motility analyses, whole mitochondrial genome sequencing assays, and bioinformatics/in silico analyses. The anticipated outcome of my research is to advance our understanding of basic biological processes, primarily in bivalves, but this knowledge will also apply to other animal groups. My research will advance our understanding of fundamental cellular processes and will be of general interest and value to geneticists, invertebrate biologists and zoologists. The advancement of pure knowledge in the area of sex determination in bivalves may have applications in the field of aquaculture and in the development of biological controls for invasive freshwater mussel species through artificial control of sex ratios. My research also has broad implications for interpreting the evolution of mitochondrial DNA. For example, my research program will provide essential data for interpreting DNA sequences for a particular gene known as Cox1, which is used as the basis of the "Consortium for the Barcode of Life" initiative. This is an attempt to use DNA sequence data to identify all species of animals in the world using a simple, inexpensive test. The correct interpretation of DNA Barcodes of native marine and freshwater mussels will be increasingly important as these species face threats from global climate change and global transport of invasive bivalve species.