Eco-Evo--Devo and the Origin and Elaboration of a Major Evolutionary Transition

Eco-Evo--Devo 以及一次重大进化转变的起源和阐述

• 批准号: RGPIN-2020-05175
• 负责人: Abouheif, Ehab
• 金额: $ 6.92万
• 依托单位: McGill University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2022
• 资助国家: 加拿大
• 起止时间: 2022-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=745598
• 关键词: Eco; Evo; Devo; Origin; Elaboration

A long-term goal of my research program is to understand the developmental genetic mechanisms underlying both the origins and elaboration of biological complexity. The history of life is marked by several major evolutionary transitions in individuality, which occur when individual organisms unite to form a higher-level individual. Examples of such major transitions include the evolution of obligate endosymbiosis - in which an unrelated host and endosymbiont unite to form a single individual, the evolution of multicellularity - in which unicellular protists unite to form multicellular organisms, and the evolution of eusociality - in which solitary insects unite to form social insect colonies. Such transitions are thought to have driven major increases in biological complexity over the course of evolution because they result in higher-level individuals with a division of labor between their constituent parts. Although biologists have begun identifying evolutionary principles shared across major transitions in individuality, little is known about the developmental genetic mechanisms that facilitated their origin and elaboration. Over the last 6 years, my lab has gained significant momentum to capitalize on several recent discoveries to uncover the developmental genetic mechanisms underlying the origin and elaboration of the transition to eusociality in ants. Ants are one of the most ecologically dominant and evolutionarily successful group of organisms on our planet. Similar to a multicellular organism with its division of labor between germline and somatic cells, an ant colony is equivalent to a `superorganism' with a reproductive division of labor between the fertile queen (the germline) and her non-reproductive workers (soma). Understanding the origin and evolution of novel castes within ant colonies may reveal general principles underlying origin and evolution of novel cell types within multicellular organisms. We will begin to uncover the developmental genetic mechanisms underlying the origin and elaboration of the transition to eusociality in ants through three research objectives: Objective 1 will test the hypothesis that programed cell death plays a key role in the origin of a novel winged queen and wingless worker caste. Objective 2 will test the hypothesis that DNA damage response pathway plays a role in elaborating the reproductive asymmetry between the queen and worker caste. Objective 3 will test the hypothesis that the wing rudiments were re-purposed into developmental signaling centers that elaborate the worker caste into a complex worker caste system. My research program has the potential to reveal that the mechanisms involved in the origin of biological complexity also function in its elaboration and will potentially reveal general mechanistic principles shared across different major transitions in individuality. My research program will further serve NSE in Canada by training 7 HQP over the course of the following five years.

我的研究计划的一个长期目标是了解生物学复杂性的起源和阐述背后的发育遗传机制。生命的历史标志着个性上的几次重大进化转变，这些转变发生在单个有机体联合起来形成更高级别的个体时。这种重大转变的例子包括专性内共生的进化--其中一个无关的宿主和内共生体结合成一个单一的个体；多细胞进化--其中单细胞原生生物联合起来形成多细胞有机体；以及共生进化--独居昆虫联合起来形成群居的昆虫群体。这种转变被认为在进化过程中推动了生物复杂性的大幅增加，因为它们导致了更高级别的个体在其组成部分之间进行分工。尽管生物学家已经开始确定在个体的重大转变中共有的进化原理，但人们对促进它们的起源和细化的发育遗传机制知之甚少。在过去的6年里，我的实验室利用最近的几项发现，获得了巨大的动力，以揭示蚂蚁向共生社会转变的起源和详细阐述背后的发育遗传机制。蚂蚁是地球上最具生态优势和进化成功的生物群体之一。类似于多细胞生物体在生殖系和体细胞之间的分工，蚂蚁群体相当于一个在有生育能力的女王(生殖系)和她的非生殖工蚁(体细胞)之间具有生殖性分工的超级有机体。了解蚂蚁群体中新种姓的起源和进化可能揭示多细胞生物体中新细胞类型起源和进化的一般原理。我们将通过三个研究目标开始揭示蚂蚁向优势性转变的起源和阐述背后的发育遗传学机制：目标1将检验程序性细胞死亡在新的有翼女王和无翅工种起源中起关键作用的假设。目的2验证DNA损伤反应通路在阐述蜂王和工蚁种姓之间生殖不对称中所起作用的假设。目标3将验证这样一种假设，即翅膀雏形被重新用于发育信号中心，该中心将工人种姓细化为复杂的工人种姓系统。我的研究计划有可能揭示生物复杂性起源中涉及的机制也在其阐述中发挥作用，并可能揭示在个性的不同主要转变中共享的一般机械原理。我的研究计划将在接下来的五年中通过培训7名HQP来进一步服务于加拿大的NSE。