IRFP: Elucidating Incipient Coevolutionary Speciation Through Experimental and Transcriptomic Approaches

IRFP：通过实验和转录组学方法阐明初期共同进化物种形成

• 批准号: 1159509
• 负责人: David Hembry
• 金额: $ 16.2万
• 依托单位: Hembry David H
• 依托单位国家: 美国
• 项目类别: Fellowship Award
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-07-01 至 2016-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1159509&HistoricalAwards=false
• 关键词: IRFP; Elucidating; Incipient; Coevolutionary; Speciation

The International Research Fellowship Program enables U.S. scientists and engineers to conduct nine to twenty-four months of research abroad. The program's awards provide opportunities for joint research, and the use of unique or complementary facilities, expertise and experimental conditions abroad. This award is co-funded by the Office of International Science and Engineering and by the Evolutionary Ecology Program in the Division of Environmental Biology. This award will support an eighteen-month research fellowship by Dr. David H. Hembry to work with Dr. Atsushi Kawakita at Kyoto University in Otsu, Japan, followed by a six-month research fellowship for Dr. Hembry to work with Dr. Michael B. Eisen at the University of California, Berkeley. The role of coevolution between species in the diversification of life on earth is one of the major questions in evolutionary biology. In particular, evidence that coevolution between species in mutualistic relationships (in which members of both species benefit) promotes diversification, as well as the mechanisms by which it might do so, remains equivocal. Specialized pollination mutualisms between insects and plants, particularly those between figs and fig wasps and yuccas and yucca moths, have long been used as models for this research because the role that pollinators play in transporting their hosts' gametes makes them especially likely candidates for coevolutionary diversification. However, evidence for coevolution driving diversification in these systems is equivocal from both empirical and theoretical angles, and few studies have explicitly investigated speciation in these systems.The goal of this proposal is to use a combination of experimental and transcriptomic approaches to examine a putative case of nascent coevolutionary speciation in a specialized, insect-plant mutualism that has recently diversified on oceanic islands in French Polynesia. Leafflower moths (Lepidoptera: Gracillariidae: Epicephala) are the sole pollinators of their leafflower plant hosts (Phyllanthaceae: Phyllanthus s. l. [Glochidion]) but their larvae consume a subset of the host's seeds in return for the service of pollination. This project will ask whether mechanisms exist that promote reciprocal specialization in this mutualism, whether such specialization leads to population differentiation in the leafflower moth pollinators, and what kinds of differences in gene expression or genome sequence are evolving in tandem with this reciprocal specialization. These questions will be addressed through a combination of methods including bioassays, flower odor analysis (GC-MS), population genetics, and transcriptomics. In doing so, this study will explicitly investigate both nascent coevolutionary speciation between coevolving organisms, and the mechanisms by which such nascent speciation occurs.An understanding of the mechanisms that give rise to biodiversity, particularly in the tropics, is vital to conserving both species diversity and interaction diversity. This research has both long-term value and short term value in this regard, since Phyllanthus trees are one of the major endemic plant radiations in the South Pacific, with many rare taxa threatened by invasive species and habitat destruction. Additionally, the use of transcriptomics in the study of host-race formation in insects has clear agricultural applications. This program will facilitate the Principal Investigator's training both in next-generation sequencing methods in evolutionary biology, and his international research experience. Finally, this project will facilitate international collaboration between the Principal Investigator and research groups at Kyoto University, Japan (Dr. Atsushi Kawakita, Dr. Makoto Kato, Dr. Tomoko Okamoto, and Dr. Hirokazu Toju), Kyoto Prefectural University, Japan (Dr. Issei Ohshima), the University of California, Berkeley (Dr. Michael Eisen), and the Délégation à la Recherche, French Polynesia (Dr. Jean-Yves Meyer).

国际研究奖学金计划使美国科学家和工程师能够在国外进行九到二十四个月的研究，该计划的奖项提供了联合研究以及使用国外独特或互补的设施、专业知识和实验条件的机会。 -由国际科学与工程办公室和环境生物学部进化生态学项目资助 该奖项将支持 David H. Hembry 博士与京都 Kawakita 博士合作的为期十八个月的研究奖学金。日本大津大学，随后为 Hembry 博士提供了为期六个月的研究奖学金，与加州大学伯克利分校的 Michael B. Eisen 博士合作。物种之间的共同进化在地球生命多样化中的作用就是其中之一。特别是，关于物种之间的共生关系（其中两个物种的成员都受益）的共同进化促进多样化的证据，以及它可能这样做的机制，仍然是模棱两可的。昆虫和植物之间的关系，特别是无花果和无花果黄蜂以及丝兰和丝兰蛾之间的关系，长期以来一直被用作这项研究的模型，因为传粉者在运输宿主配子方面所发挥的作用使它们特别有可能成为共同进化多样化的候选者。从经验和理论角度来看，共同进化驱动这些系统多样化的证据是模棱两可的，很少有研究明确调查这些系统中的物种形成。该提案的目标是结合使用实验和转录组学方法来研究一种特殊的昆虫-植物互利共生的新生共同进化物种形成的假定案例，这种共生最近在法属波利尼西亚的海洋岛屿上多样化，叶花蛾（鳞翅目：Gracillariidae：Epicephala）是其叶花植物寄主的唯一传粉者。叶下珠科：Phyllanthus s. [Glochidion]），但它们的幼虫消耗了一部分该项目将询问是否存在促进这种互利共生中互惠专业化的机制，这种专业化是否会导致叶花蛾授粉昆虫的群体分化，以及基因表达或基因组序列有哪些差异。这些问题将通过生物测定、花气味分析 (GC-MS)、群体遗传学和转录组学等方法的组合来解决。将明确研究共同进化生物之间的新生共同进化物种形成，以及这种新生物种形成发生的机制，了解产生生物多样性的机制，特别是在热带地区，对于保护物种多样性和相互作用多样性至关重要。在这方面具有长期价值和短期价值，因为叶下珠树是南太平洋主要的特有植物辐射之一，许多稀有类群受到入侵物种和栖息地破坏的威胁。昆虫宿主种族形成研究中的转录组学具有明显的农业应用价值，该项目将促进首席研究员在进化生物学下一代测序方法方面的培训，并促进他的国际研究经验。日本京都大学（Atsushi Kawakita 博士、Makoto Kato 博士、Tomoko Okamoto 博士和 Hirokazu Toju 博士）、日本京都府立大学（Dr. Issei Ohshima）、加州大学伯克利分校（Michael Eisen 博士）和法属波利尼西亚研究代表团（Jean-Yves Meyer 博士）。