Evolution of Novel Ontogenies

新个体发育的进化

• 批准号: 0234576
• 负责人: Rudolf Raff
• 金额: $ 45万
• 依托单位: Indiana University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-04-01 至 2007-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0234576&HistoricalAwards=false
• 关键词: Evolution; Novel; Ontogenies

0234576RaffThe goal of this project is to understand the mechanisms by which development evolves, and how developmental processes influence or constrain the direction of evolution. Two related species of sea urchins with highly different modes of early development are being used in this study. Heliocidaris tuberculata develops in the ancestral indirect mode via a feeding larva, whereas H. erythrogramma develops directly from embryo to juvenile adult. Eggs of H. erythrogramma fertilized by H. tuberculata sperm develop via a novel pathway in which a number of the primitive pluteus features are restored by the action of dominant factors derived from the paternal genome. Dr. Raff has exploited the restoration of pluteus-like gene expression in a restored pluteus tissue, oral ectoderm, to identify candidate regulatory genes involved in evolution of developmental mode. A hypothesis for evolutionary change in larval form of H. erythrogramma will be tested, and genes underlying evolution of both larval and maternal features will be studied through functional assays. The specific aims are (1) Determine the functional roles of regulatory genes in indirect, direct, and hybrid embryos. Gain of function studies will be done with presumptive dominant regulatory genes selected for known roles in organization of indirect-developers. These will be expressed inH. erythrogramma embryos as injected mRNAs to determine which larval features are restored by transcription factor mRNAs. (2) Determine the functional roles of genes affecting primary larval axes and their evolution. Functions of candidate genes will be studied by misexpression of mRNAs that include those encoding signal system components, transcription factors, and knockout/knockdown constructs for these components. (3) Use cross-species hybrids to investigate cell lineage transformations and novel gene expression patterns. He will use cell lineage tracing in hybrids to define which blastomeres shift fate to become oral ectoderm, as well as other cell lineage changes. Meeting NSF Review Criteria: (1) Intellectual merit of the proposed activity: The project will advance knowledge by determining how the function of developmental regulatory genes influences the evolution ofdevelopment. The project will contribute to a new discipline in biology. The project makes use of unique organisms and resources in Australia, and includes long-term collaborations with Australian scientists. (2) Broader impacts of the proposed activity: The main societal impact is to help create a more integrated view of biological evolution. This is important in teaching evolution in a realistic way in biology classes at secondary and college levels. In addition, the work itself has been cited in college text books, (Freeman and Herron, Evolutionary Analysis, Prentice Hall, 2001; Wilt and Hake, Principles of Developmental Biology, Norton, 2001, and Gilbert, Developmental Biology, Sinauer, 2000), and the popular press (Washington Post, October, 2000, and National Geographic, May 2000), which helps create a greater public understanding of research in biology.

0234576Raff 该项目的目标是了解发育演化的机制，以及发育过程如何影响或约束演化的方向。 这项研究使用了早期发育模式截然不同的两种相关海胆物种。 Heliocidaris tuberculata 通过摄食幼虫以祖先间接模式发育，而 H. erythrogramma 直接从胚胎发育到幼年成虫。 H. erythrogramma 的卵由结核 H. tuberculata 精子受精，通过一种新的途径发育，在该途径中，通过来自父本基因组的主导因子的作用恢复了许多原始的 puteus 特征。 拉夫博士利用恢复的大脑组织（口腔外胚层）中大脑样基因表达的恢复来识别参与发育模式进化的候选调控基因。 将测试红眼红眼藻幼虫形式进化变化的假设，并将通过功能测定来研究幼虫和母体特征进化的基因。 具体目标是（1）确定调控基因在间接、直接和混合胚胎中的功能作用。 功能增益研究将使用在间接开发者组织中选择的已知作用的推定显性调节基因来完成。 这些将用H表示。红眼病胚胎注射 mRNA，以确定转录因子 mRNA 恢复了哪些幼虫特征。 (2)确定影响初级幼虫轴及其进化的基因的功能作用。 将通过 mRNA 的错误表达来研究候选基因的功能，这些 mRNA 包括编码信号系统组件、转录因子和这些组件的敲除/敲低构建体。 (3) 使用跨物种杂交来研究细胞谱系转化和新的基因表达模式。 他将利用杂交种中的细胞谱系追踪来确定哪些卵裂球转变命运，成为口腔外胚层，以及其他细胞谱系变化。 符合 NSF 审查标准： (1) 拟议活动的智力价值：该项目将通过确定发育调控基因的功能如何影响发育的进化来推进知识。 该项目将为生物学的新学科做出贡献。 该项目利用澳大利亚独特的生物和资源，并包括与澳大利亚科学家的长期合作。 (2) 拟议活动的更广泛影响：主要的社会影响是帮助建立对生物进化更加综合的看法。 这对于在中学和大学生物学课程中以现实的方式教授进化论非常重要。 此外，这项工作本身也被大学教科书（Freeman and Herron，Evolutionary Analysis，Prentice Hall，2001；Wilt and Hake，Principles of Developmental Biology，Norton，2001；Gilbert，Developmental Biology，Sinauer，2000）和大众媒体（《华盛顿邮报》，2000 年 10 月，《国家地理》，2000 年 5 月）引用，这有助于建立更广泛的公众视野。对生物学研究的理解。