CAREER: Discovering the Developmental Genetic Basis for Parallel Evolution of Aerial Respiration in Arthropods

职业：发现节肢动物空中呼吸平行进化的发育遗传基础

• 批准号: 1552610
• 负责人: Prashant Sharma
• 金额: $ 85万
• 依托单位: University of Wisconsin-Madison
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-03-01 至 2022-02-28
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1552610&HistoricalAwards=false
• 关键词: CAREER; Discovering; Developmental; Genetic; Basis

The movement from water to land was a critical evolutionary transformation for both vertebrates and arthropods (insects, spiders, millipedes, crustaceans, etc.). Different groups of arthropods used different methods to enable breathing air, a critical requirement for life on land, a change that occurred separately in at least 7 groups. The goal of this project is to investigate how an air-breathing respiratory system evolved separately in multiple arthropod groups. Did evolution of aerial respiration involve alteration to the same anatomical structures and genes in each group, or does each arthropod group use a different solution to the problem of breathing air? To resolve this question, the embryonic formation of respiratory organs in eight arthropod species will be investigated. Genes and proteins will be tested to determine whether the same genes are used in the respiratory system of all arthropods. Genome sequencing will further test and identify genes that create unique respiratory structures (e.g., the book lung of spiders). The outcomes of this research will be integrated into a new laboratory-based course on invertebrate zoology, to be taught annually through the Department of Zoology, using live specimens. A museum exhibit will be developed on the movement of arthropods onto land, and using evidence from fossils, genes, and developmental biology. One postdoctoral fellow, one graduate student, and ten summer undergraduates will be trained during the work, emphasizing recruitment of women and underrepresented groups in science.Investigating the parallel evolution of aerial respiration in Arthropoda has previously been limited to studies of functional morphology or expression data from a few taxa. Some developmental data suggest that mandibulate and chelicerate respiratory systems are directly homologous, whereas a separate set of data suggests that respiratory organs of arachnids arose independently from modified walking legs. Respiratory systems of Myriapoda have not been studied in a developmental genetic context at all. To resolve the origins of internalized respiratory systems of arthropods, the proposed work will examine positional, genetic, and serial homology of respiratory organs in eight emerging model arthropod systems. To establish the serial homology of arachnid respiratory organs, Hox misexpression experiments will be conducted to derepress appendages in posterior segments. To establish degree of conservation of the gene regulatory network (GRN) underlying tubulogenesis across Arthropoda, gene expression assays will be performed for candidate genes known to be required for establishment of the Drosophila melanogaster tracheal tubule system. To assess functional correspondence, knockdown experiments will be conducted in two chelicerate and three mandibulate exemplars for five critical genes in the Drosphila GRN. To investigate the patterning of the arachnid book lung, comparative transcriptomic data will be generated from book lung primordia of spiders and scorpions, toward identifying a set of novel candidate genes putatively involved in book lung morphogenesis for further functional screening. This work will directly address the two competing scenarios of arthropod terrestrialization that persist in the literature, using independent tests of positional, serial, and genetic homology.

对于脊椎动物和节肢动物（昆虫、蜘蛛、千足虫、甲壳类动物等）来说，从水到陆地的迁移是一个关键的进化转变。 不同类群的节肢动物使用不同的方法来呼吸空气，这是陆地生命的关键要求，这种变化至少在 7 个类群中分别发生。 该项目的目标是研究多个节肢动物群体的呼吸空气的呼吸系统是如何单独进化的。 空气呼吸的进化是否涉及每个群体中相同解剖结构和基因的改变，或者每个节肢动物群体是否使用不同的解决方案来解决呼吸空气的问题？ 为了解决这个问题，将研究八种节肢动物呼吸器官的胚胎形成。 将测试基因和蛋白质，以确定所有节肢动物的呼吸系统中是否使用相同的基因。 基因组测序将进一步测试和识别创造独特呼吸结构（例如蜘蛛的书肺）的基因。 这项研究的成果将被纳入一门新的基于实验室的无脊椎动物学课程，该课程每年通过动物学系使用活体标本进行教学。 博物馆展览将利用来自化石、基因和发育生物学的证据，以节肢动物在陆地上的运动为主题。 工作期间将培训一名博士后研究员、一名研究生和十名暑期本科生，重点是招募女性和科学领域代表性不足的群体。对节肢动物空中呼吸的平行进化的研究此前仅限于对几个类群的功能形态或表达数据的研究。一些发育数据表明，下颌呼吸系统和螯肢呼吸系统是直接同源的，而一组单独的数据表明，蛛形纲动物的呼吸器官独立于改良的步行腿而产生。多足纲的呼吸系统尚未在发育遗传背景下进行过研究。为了解决节肢动物内化呼吸系统的起源，拟议的工作将检查八种新兴模型节肢动物系统中呼吸器官的位置、遗传和序列同源性。为了建立蛛形纲动物呼吸器官的系列同源性，将进行 Hox 错误表达实验以去抑制后段的附属物。为了确定节肢动物小管发生的基因调控网络（GRN）的保守程度，将对已知建立果蝇气管小管系统所需的候选基因进行基因表达测定。为了评估功能对应性，将对果蝇 GRN 中五个关键基因的两个螯肢动物和三个下颌动物样本进行敲除实验。为了研究蜘蛛书肺的模式，将从蜘蛛和蝎子的书肺原基中生成比较转录组数据，以确定一组可能参与书肺形态发生的新候选基因，以进行进一步的功能筛选。这项工作将使用位置、序列和遗传同源性的独立测试，直接解决文献中持续存在的节肢动物陆化的两种相互竞争的情况。

项目成果

Systemic paralogy and function of retinal determination network homologs in arachnids.

• DOI: 10.1186/s12864-020-07149-x
• 发表时间: 2020-11-23
• 期刊: BMC genomics
• 影响因子: 4.4
• 作者: Gainett G;Ballesteros JA;Kanzler CR;Zehms JT;Zern JM;Aharon S;Gavish-Regev E;Sharma PP
• 通讯作者: Sharma PP

The genome of a daddy-long-legs (Opiliones) illuminates the evolution of arachnid appendages

• DOI: 10.1098/rspb.2021.1168
• 发表时间: 2021-08-11
• 期刊: PROCEEDINGS OF THE ROYAL SOCIETY B-BIOLOGICAL SCIENCES
• 影响因子: 4.7
• 作者: Gainett, Guilherme;Gonzalez, Vanessa L.;Sharma, Prashant P.
• 通讯作者: Sharma, Prashant P.