RII Track-4: A role for epigenetic modifications driving seasonal patterns of reproduction?

温带和北极地区全年的环境条件变化很大。对于能够在这些环境中成功养育后代的动物来说，繁殖必须限制在短时间内，以确保有利的条件（即温和的温度和丰富的食物资源）。虽然之前的研究已经揭示了雄性动物是如何为交配做准备的，但对于雌性动物是如何精确地选择繁殖时间（也就是后代出生或孵化的时间）的，我们知之甚少，尽管最终决定后代养育时间的是雌性的时间。个体表达的特征（即表型）是由动物的遗传和环境之间的相互作用形成的。这一项目将使哥伦比亚大学能够进行培训和技术和技能的知识转让，目的是揭示能够对环境作出反应并调节影响女性生殖时间决定的关键基因的表达的遗传过程。这种培训和知识转移将提高PI实验室的研究能力，并促进PI在北达科他州立大学的母校和其他机构之间的未来合作。这些知识不仅有助于建立坚实的基础知识，而且还具有加强动物家畜育种计划（例如，羊是季节性育种者）以提高经济生产力的潜力。技术描述生物体的表型是其基因组和环境相互作用的结果。理解影响个体进化适应性的过程（即终生生殖成功）需要对塑造个体表型的分子结构进行研究。环境影响基因表达（产生表型）的一种主要方式是通过表观遗传修饰。一个人生育和成功养育后代的能力直接决定了一个人的性格。S进化适应性。居住在温带或北极地区的动物，繁殖必须限制在一个短时间窗口内，以确保有有利的条件来养育后代。调节蛋黄前体蛋白产生的DNA的季节性表观遗传修饰可能会产生适当的年度反应，在一年中不适当的时间（例如，冬末温暖期）经历有利条件时抑制蛋黄前体的产生，而在适当的季节经历有利条件时使蛋黄前体产生。利用一种季节性繁殖的鸣禽模型，黑眼Junco (Junco hyemalis)，该提案将验证一个新的假设，即卵泡形成和最终卵泡成熟所需的重要基因调控区域的DNA甲基化是季节性调节的。该项目将提供技能和工具的培训和知识转移，用于发现可能影响个体表型和适应性的表观遗传修饰。在哥伦比亚大学接受的检测基因组甲基化方法的培训将使我们的研究小组能够验证一个假设，即季节信息影响基因启动子区域的表观遗传调节，该基因是蛋黄前光标蛋白卵黄原蛋白（VTG）的关键编码。

Non-technical DescriptionTemperate and arctic regions experience dramatic variations in environmental conditions across the year. For animals to be able to successfully rear offspring in these environments, reproduction must be limited to a short window of time that ensures favorable conditions (i.e., mild temperatures and abundant food resources). While prior research has revealed how male animals prepare for mating, much less is known regarding how females precisely time reproduction (and thus, the time when offspring are born or hatch), even though it is female timing that ultimately dictates when rearing of offspring will occur. Traits expressed by an individual (i.e., phenotype) are shaped by interactions between an animal's genetics and the environment. This project will enable training at Columbia University and knowledge transfer of techniques and skills aimed at uncovering the genetic processes that are capable of responding to the environment and regulating expression of key genes to influence female reproductive timing decisions. This training and knowledge transfer will enhance the research capabilities of the PI's laboratory and facilitate future collaborations within the PI's home institution of North Dakota State University and beyond. Such knowledge will not only contribute to robust basic knowledge, but also has the potential to enhance animal livestock breeding programs (e.g., sheep, which are seasonal breeders) to enhance economic productivity.Technical DescriptionAn organism's phenotype is the result of interactions between its genome and the environment. Understanding the processes that influence an individual's evolutionary fitness (i.e. lifetime reproductive success) requires investigations of the molecular architecture that shape an individual's phenotype. One primary way whereby the environment can influence which genes are expressed (which gives rise to the phenotype) is via epigenetic modification. The ability of an individual to produce and successfully rear young directly dictates an individual?s evolutionary fitness. In animals inhabiting temperate or arctic clines, reproduction must be limited to a short window of time that ensures favorable conditions for rearing offspring. Seasonal epigenetic modification of the DNA regulating production of yolk-precursor proteins may enable appropriate annual responses, inhibiting production of yolk precursors when favorable conditions are experienced at inappropriate times of year (e.g., the late winter warm period) while enabling yolk precursor production when favorable conditions are experienced in the appropriate season. Utilizing a songbird model of seasonal breeding, the Dark-eyed Junco (Junco hyemalis), this proposal will test the novel hypothesis that methylation of DNA in the regulatory region of an important gene needed for yolking and final follicle maturation is seasonally modulated. This project will provide training and transfer of knowledge of the skills and tools utilized to uncover epigenetic modifications that may influence an individual's phenotype and fitness. The training received at Columbia University for methods of detecting methylation in the genome will allow our group to test the hypothesis that seasonal information influences epigenetic modulation of the promoter region of a gene the codes for a key yolk pre-cursor protein, vitellogenin (VTG).