The Role of Developmental Genes in Controlling Butterfly Eyespot Patterns II

发育基因在控制蝴蝶眼斑模式中的作用 II

• 批准号: 0653399
• 负责人: Antonia Monteiro
• 金额: --
• 依托单位: Yale University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-07-09 至 2009-10-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0653399&HistoricalAwards=false
• 关键词: Role; Developmental; Genes; Controlling; Butterfly

The emerging field of evo-devo studies, in part, how genotype connects to phenotype. This project seeks to test the function of a few candidate transcription factors in the development of butterfly eyespots. Several transcription factors and gene circuits that are known to be involved in wing and leg development in Drosophila are hypothesized to be involved in the development of eyespots in butterflies. In particular, when Distal-less (Dll) is ectopically activated in Drosophila it causes complete leg duplications, thus suggesting a master regulatory function. In Bicyclus, Dll is expressed in signaling cells in the eyespot's center at the earliest stages of eyespot development, and moreover, variation in Dll is linked with variation in eyespot size. Have butterflies co-opted the same "leg" developmental circuit in the formation of eyespots? An activated ligand receptor, phosphorylated Mothers Against Decapentaplegic, pMad, is expressed in the eyespot field during early pupal development. Is the morphogen Decapentaplegic (Dpp) being produced at the eyespot's center, diffusing to surrounding cells and differentiating a complete eyespot pattern? Another transcription factor, Engrailed (En), is expressed in a ring of epidermal cells that correlates with the pattern of gold colored scales on the eyespot of the adult Bicyclus wing. Does En cause the differentiation of gold colored scales in eyespots? The experiments outlined in this project test these hypotheses by ectopically expressing Dll, Dpp, and En on the developing wing and observing whether, in the first two cases, a complete eyespot pattern differentiates around the site of expression, or whether, in the second case, gold scales develop at the site of expression. Additional experiments will test whether over-expressing Dll and Dpp at the eyespot's center will lead to differences in eyespot size. To induce ectopic expression the lab has developed a laser-assisted heat-shocking technique that will allow the activation of these genes in a controlled spatial and temporal fashion on the developing wing of transgenic butterflies. The heat-shocking technique has been successfully tested with a fluorescent marker gene but now this marker will be substituted for the coding sequences of Dll, Dpp, and En. Establishing a causal relationship between these genes and differentiation of eyespots or colored scales will allow the later examination of the relationship between the evolution of these genes and the evolution of the phenotype. Intellectual merit: Much work in evo-devo has been dominated by inferring novel functions for genes based solely on their novel expression domains. This project intends to go beyond the correlational evidence and to really test whether "old" developmental genes belonging to known gene circuits have been functionally co-opted to specify a morphological novelty in evolution, butterfly eyespots. Once this functional co-option is established future work will attempt to track the evolution of eyespots, from their creation throughout their various levels of quantitative and qualitative modifications. This long-term study will dissect the evolution of regulatory genes with a demonstrated key role in differentiating these adaptive traits. This project aims to test whether a few candidate genes display that key role. In addition, this project will make available a series of transformation constructs of wide applicability across organisms, as well as develop important tools for functional genetics in non-model organisms. Broader Impacts: Dr. Monteiro has currently involved one postdoc and 3 graduate students in this project. One is a woman and a member of the Native American tribe Choctaw Nation of Oklahoma. Another is a minority graduate student in the Department of Electrical Engeneering at Buffalo. These two students are both recipients of NSF IGERT training grants in Biophotonics, and are truly working at the interface of Biology and Photonics via an established collaboration with the Department of Electrical Engineering at Buffalo. She will continue to train graduate and undergraduates students alike in Population Genetics, Phylogenetics, and Developmental Biology, irrespective of gender and ethnicity, in order to provide them with a broad multifaceted approach to Evolution and Development.

新兴的进化-发育研究领域部分研究基因型与表现型的联系。本项目旨在测试几个候选转录因子在蝴蝶眼斑发育中的功能。一些已知参与果蝇翅膀和腿发育的转录因子和基因回路被假设参与蝴蝶眼点的发育。特别是，当远侧少（Dll）异位激活果蝇，它会导致完整的腿复制，从而表明一个主调节功能。在Bicyclus中，Dll在眼斑发育的最早阶段在眼斑中心的信号细胞中表达，而且，Dll的变化与眼斑大小的变化有关。蝴蝶在眼斑的形成过程中是否也采用了同样的“腿”发育回路？一种激活的配体受体，磷酸化的母亲对Decapentaplegic，pMad，在早期蛹发育过程中的眼点领域表达。是形态原Decapentaplegic（Dpp）产生于眼点的中心，扩散到周围的细胞，并分化出一个完整的眼点模式？另一种转录因子Engrailed（En）在表皮细胞环中表达，与成年Bicyclus翅膀上的眼点上的金色鳞片图案相关。En是否引起了眼斑中金色鳞片的分化？在这个项目中概述的实验测试这些假设异位表达Dll，Dpp，和En的发展翅膀，并观察是否，在前两种情况下，一个完整的眼斑图案区分周围的网站的表达，或是否，在第二种情况下，金鳞片在网站的表达。另外的实验将测试在眼点中心过度表达Dll和Dpp是否会导致眼点大小的差异。为了诱导异位表达，该实验室开发了一种激光辅助热休克技术，该技术将允许这些基因在转基因蝴蝶发育中的翅膀上以受控的空间和时间方式激活。热休克技术已经成功地测试了荧光标记基因，但现在这个标记将取代Dll，Dpp和En的编码序列。建立这些基因与眼点或有色鳞片分化之间的因果关系将允许以后检查这些基因的进化与表型进化之间的关系。智力优势：进化发育中的许多工作都是基于新的表达结构域来推断基因的新功能。该项目旨在超越相关性证据，真正测试属于已知基因回路的“旧”发育基因是否在功能上被增选，以指定进化中的形态学新奇，蝴蝶眼点。一旦这种功能的共同选择建立未来的工作将试图跟踪眼点的演变，从他们的创造，通过他们的各种水平的定量和定性的修改。这项长期研究将剖析调控基因的进化，并证明其在区分这些适应性特征方面的关键作用。该项目旨在测试一些候选基因是否显示出这种关键作用。此外，该项目还将提供一系列广泛适用于生物体的转化构建体，并为非模式生物的功能遗传学开发重要工具。更广泛的影响：Monteiro博士目前在这个项目中涉及一名博士后和3名研究生。其中一个是一名妇女，是俄克拉荷马州美洲土著部落乔托族的成员。另一个是布法罗电气工程系的少数民族研究生。这两名学生都是NSF IGERT生物光子学培训赠款的获得者，并通过与布法罗电气工程系的既定合作，真正在生物学和光子学的接口工作。她将继续培养研究生和本科生都在人口遗传学，系统发育学和发育生物学，不分性别和种族，以便为他们提供一个广泛的多方面的方法来进化和发展。