Adaptive transgenerational signaling; maternal and paternal effects on early life history in salmon

我们知道，当地的环境条件，如污染和温度变化，会导致生物体早期生命阶段的相应变化，这些变化反映在DNA水平上。这些环境变化可能很快，需要生物体同样迅速地适应和进化，否则就会面临灭绝。这种强烈的选择和快速的进化不符合经典的遗传选择模型，那么是什么让这些生物能够迅速改变它们早期生命阶段的方式来应对当地环境条件的变化呢？我以前的NSERC研究重点是描述鱼类早期生活史的变化，特别是鲑鱼。这项工作的结果使我得出结论，与广泛持有的理论相反，生命早期阶段的快速，反应性进化部分（甚至大部分）是由于经典遗传遗传之外的母体和父亲的影响，通过跨代信号（“TS”）影响后代。虽然母体效应已经在整个分类群中被发现（父亲效应尚未被广泛研究），但我们对它们的适应潜力或它们工作的亚细胞机制知之甚少。因此，这一提议解决了关于TS作为快速适应的进化力量的三个重要问题：1）“TS的遗传、表观遗传和环境成分是什么？TS的亚细胞机制是什么？TS是否对后代的适应性有可测量的益处？“通过回答奇努克鲑鱼和虹鳟鱼种群中的这些问题，我将确定TS是否是鲑鱼当地适应的主要驱动力。具体来说，我将操纵母亲和父亲的环境独立嵌套育种实验，允许直接的母亲和父亲的影响估计。我将探索特定的亚细胞（表观遗传）因素有助于TS，并确定这些信号的变化如何影响后代的健身。我提出的研究计划将对基础科学和应用科学都有重要意义。虽然有许多快速进化的例子，但我的研究将有助于我们理解这种进化是如何发生的。具体来说，我的NSERC研究将有助于进化和生态理论重新定义TS作为一个令人兴奋的和新颖的范例，为当地适应环境变化和压力的快速进化。应用的结果将不仅限于鲑鱼，甚至鱼类，但将适用于所有脊椎动物表现出当地的适应。管理人员和保护生物学家将改变他们保护当地种群的工作方式：保护的单位将从“种群”转变为“TS剖面”。“孵化场管理人员（政府和水产养殖业）将重点关注在育种前如何对待父母，以提高重新引入，补充和商业养殖的成功。

We know that local environmental conditions, like pollution and temperature changes, cause corresponding changes in early life stages of organisms that are reflected at the DNA level. These environmental changes can be rapid, and require the organism to adapt and evolve equally rapidly or face extinction. This strong selection and rapid evolution does not fit into a classical genetic selection model, so what is allowing these organisms to quickly alter the way their early life stages play out in response to changes in local environmental conditions? My previous NSERC research focused on characterizing early life history variation in fish, with a particular focus on salmon. The results of that work have led me to conclude that-contrary to widely-held theories-the rapid, responsive evolution of early life stages is partly (or even mostly) due to maternal and paternal effects outside of classical genetic inheritance that affect offspring through transgenerational signaling ("TS"). While maternal effects have been found across taxa (paternal effects have not been as widely studied), we know very little about their adaptive potential or the subcellular mechanisms through which they work. So, this proposal addresses three important questions about TS as an evolutionary force for rapid adaptation: 1) "What are the genetic, epigenetic and environmental components of TS?", 2) "What are the sub-cellular mechanisms of TS?", and 3) "Does TS provide a measureable benefit for offspring fitness?" By answering those questions among populations of Chinook salmon and rainbow trout, I will determine if TS is a major driver of local adaptation in salmon. Specifically, I will manipulate maternal and paternal environments independently in nested breeding experiments, allowing direct maternal and paternal effect estimation. I will explore the specific sub-cellular (epigenetic) factors contributing to TS, and determine how variation in those signals affect offspring fitness. My proposed research program will have important implications for both basic and applied sciences. Although there are many examples of rapid evolution, my research will contribute to our understanding of how this evolution takes place. Specifically, my NSERC research will contribute to evolutionary and ecological theory by redefining TS as an exciting and novel paradigm for rapid evolution of local adaptation to environmental variation and stress. The applied outcomes will not be limited to salmon, or even fishes, but would apply to all vertebrates exhibiting local adaptation. Managers and conservation biologists will change how they work to preserve local populations: the unit of conservation would switch from "populations" to "TS profiles." Hatchery managers (both government and aquaculture) will focus on how the parents are treated prior to breeding to improve reintroduction, supplementation and commercial culture success.