Molecular Mechanisms and Evolution of Phenotypic Plasticity

从植物到人类，生物体的多样性令人难以置信。它的无处不在证明了 它在生活中的重要性。这个项目解决了迷人的和未充分研究的问题， 表型可塑性的机械基础-即，发展过程如何受到 环境因素导致表型差异--以及，重要的是，这些过程是如何进化的。的 这里的重点是一个创新的模式，豌豆蚜虫，它展示了一个教科书的例子，表型 可塑性这个物种提供了一个无与伦比的机会来研究自然和养育的作用， 表型确定：它表现出显着不同的有翼和无翼的形态，这是由 环境条件下遗传相同，无性雌性和控制的单一遗传位点， 男性。因此，引人注目的是，两个二态性，每个在不同的控制机制下，存在于这个单一的 物种拟议的实验建立在PI最近关于以下作用的令人兴奋的发现之上： 激素和水平转移基因在雌鸟翅可塑性中的作用， 翼多态性基因座在男性，其中有一个插入含有重复的基因，影响 信号（卵泡抑素），这是具体的无翅男性。拟议中的积极研究计划旨在 破译可塑性功能和进化的分子机制。的实验 翅膀可塑性将检查控制它的调节变化，伴随它的表观遗传变化， 并测试水平转移的基因是否优先被招募到该过程中。的实验 遗传雄性翼二型性将使用卵泡抑素旁系同源物的功能和进化研究来建立 这些旁系同源物的变化是如何成为雄性形态进化的基础的。女性和男性研究将 结合实验，将测试是否最近派生的男性二型性进化， 女性可塑性的遗传调节，假设男性绕过环境信号 女性的可塑性。这些研究将提供一些第一次深入了解的机械基础， 遗传适应，即性状变异从“后天”引起的转变为“自然”引起的。这些 实验将对理解可塑性的机械基础和进化具有广泛的意义， 从人类健康的角度来看，这是很重要的，因为有许多塑料特性会影响 人类健康和疾病。

Phenotypic plasticity is used by an incredible diversity of organisms, from plants to humans. Its ubiquity attests to its fundamental importance in life. This project addresses the fascinating and understudied question of the mechanistic basis of phenotypic plasticity – i.e., how developmental processes are influenced by environmental cues to cause phenotypic differences -- and, importantly, how those processes evolve. The focus here is on an innovative model, the pea aphid, which exhibits a textbook example of phenotypic plasticity. This species offers an unparalleled opportunity to examine the role of nature and nurture in phenotype determination: it exhibits dramatically different winged and wingless morphs that are induced by environmental conditions in genetically identical, asexual females and controlled by a single genetic locus in males. Thus, strikingly, two dimorphisms, each under different control mechanisms, exist within this single species. The proposed experiments build on the exciting recent discoveries made by the PI about the role of hormones and horizontally transferred genes in the female wing plasticity and about the identification of the wing polymorphism locus in males, which has an insertion containing a duplication of a gene that influences signaling (follistatin) and which is specific to wingless males. The proposed, vigorous research program aims to decipher the molecular mechanisms underlying the function and evolution of plasticity. Experiments on the wing plasticity will examine the regulatory changes that control it, the epigenetic changes that accompany it, and test if horizontally transferred genes are preferentially recruited into the process. Experiments on the genetic male wing dimorphism will use functional and evolutionary studies of the follistatin paralogs to establish how changes in these paralogs underlie male morphological evolution. Studies in females and males will be united with experiments that will test whether or not the more recently derived male dimorphism evolved by genetic accommodation of the female plasticity, hypothesizing that males bypass the environmental signals used by the female plasticity. These studies will provide some of the first insights into the mechanistic basis of genetic accommodation, where trait variation shifts from being caused by “nurture” to “nature”. These experiments will have broad implications for understanding the mechanistic basis and evolution of plasticity, which is significant from a human health perspective because of the numerous plastic traits that influence human health and disease.