A Phylogeny of Major Metazoan Radiations

主要后生动物辐射的系统发育

• 批准号: 9807100
• 负责人: Wesley Brown
• 金额: $ 20万
• 依托单位: Regents of the University of Michigan - Ann Arbor
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-09-15 至 2001-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9807100&HistoricalAwards=false
• 关键词: Phylogeny; Major; Metazoan; Radiations

9807100 Brown, Wes Mitochondrial DNA (mtDNA) of animals is a small, extrachromosomal genome typically about 16 kilobases and containing 37 genes. MtDNA comparisons among major animal groups suggest several generalities: 1) With the exception of some cnidarian mtDNAs, and otherwise for a single protein-encoding gene (ATP8), gene content is invariant, consisting of 37 genes. 2) Gene arrangements commonly remain unchanged over long periods of evolutionary time. 3) There is little selection for particular gene arrangements. 4) The great number of potential gene rearrangements makes convergence in different lineages unlikely. 5) With few exceptions, gene arrangements seem stable within major groups, but variable between them. All of these characteristics make the comparison of mitochondrial gene arrangements a powerful means for inferring ancient phylogenetic relationships. From these comparisons we have been able to infer several higher level evolutionary relationships for which all other types of data had been equivocal. We intend to determine the complete mitochondrial DNA sequences and gene arrangements of an animal representing each of the following groups: The crustacean groups Remipedia and Maxillopoda, Myriapoda, Pentastoma, Priapula, Phoronida, Ectoprocta, the brachiopod groups Articulata and Inarticulata, the mollusk groups Cephalopoda and Scaphopoda, the annelid groups Polychaeta and Hirudinea, Pogonophora, Sipuncula, Echiura, Nematoda, and Platyhelminthes. We will compare these cladistically, along with many published gene arrangements, as well as compare DNA and inferred amino acid sequences in order to infer evolutionary relationships among higher metazoan groups.

[807100 Brown， Wes]动物的线粒体DNA （mtDNA）是一个小的染色体外基因组，通常约有16千碱基，包含37个基因。主要动物类群的MtDNA比较显示出以下几个共性：1)除了一些刺胞动物的MtDNA外，其他单个蛋白质编码基因（ATP8）的基因含量是不变的，由37个基因组成。基因排列通常在长时间的进化过程中保持不变。3)对特定基因排列的选择很少。大量潜在的基因重排使得不同谱系不可能趋同。除了少数例外，基因排列在主要群体内似乎是稳定的，但在不同群体之间则是可变的。所有这些特征使线粒体基因排列的比较成为推断古代系统发育关系的有力手段。从这些比较中，我们已经能够推断出一些更高层次的进化关系，而所有其他类型的数据都是模棱两可的。我们打算确定一种动物的完整线粒体DNA序列和基因排列，这些动物代表以下每一个群体：甲壳类动物群remimedia和Maxillopoda， Myriapoda, Pentastoma, Priapula, Phoronida, Ectoprocta，腕足类动物群Articulata和Inarticulata，软体动物群Cephalopoda和scaphopda，多毛纲和Hirudinea， Pogonophora, Sipuncula, Echiura， Nematoda和platyhelmintes。我们将比较这些分支，以及许多已发表的基因排列，以及比较DNA和推断的氨基酸序列，以推断高等后生动物群体之间的进化关系。