Epigenetic regulation of seasonal behavior in insects

许多动物会根据环境的季节变化而改变它们的行为。大脑中发生的以季节性方式改变行为的变化的分子本质仍然知之甚少。该项目将研究表观遗传变化，即DNA外部修饰的变化，这些变化以季节依赖的方式打开或关闭行为调节基因。这项工作将使用行为方法和长距离迁徙的帝王蝶Danaus plexippus的基因组DNA测序进行。帝王蝶在个体水平上表现出极端的季节性行为变化，以应对不断变化的日照长度和温度。迁徙的帝王蝶在秋天向南飞行，完成了从美国到墨西哥越冬地的2,000英里的非凡旅程。在春天，迁徙的蝴蝶将它们的飞行方向转向北方，返回美国。该项目将揭示这些季节性形式大脑中基因组的季节性表观遗传变化。这些发现将提供深入了解的分子机制的季节性迁移和生产不同的季节性飞行方向，并可能适用于其他迁徙物种。它们也可能对保护策略产生影响，以帮助保护标志性的君主迁徙，这是一种壮观但受到威胁的生物现象。该项目将为对动物行为，神经科学和生物信息学感兴趣的学生提供有价值的研究培训，包括来自STEM领域代表性不足的群体的学生。研究人员还将开展外展活动，致力于提高公众对帝王蝶栖息地保护工作的必要性的认识。季节性行为适应是许多动物生态成功的关键。在个体中观察到的对环境季节性变化的反应的行为可塑性强烈表明表观遗传学在形成季节性行为中起着至关重要的作用。然而，将大脑功能与行为的季节性调节联系起来的表观遗传变化在很大程度上仍然未知。该项目将利用帝王蝶迁徙行为对环境（日照长度，温度）季节性变化的显着季节性可塑性来描绘大脑中作为季节性迁徙行为和飞行方向基础的全基因组表观遗传结构。该项目的目标是确定活性顺式调节元件（克雷斯）和推定的转录因子（TF），介导非移民，秋季移民和春季移民大脑中的差异基因表达。研究人员将在受控条件下使用秋季移民和秋季移民重新编程为春季移民，并结合下一代测序技术。在这些季节性形式的大脑中差异表达的基因将通过RNA-seq鉴定，并且介导这种差异表达的开放基因组调控区和克雷斯将通过组蛋白标记的ATAC-seq和ChIP-seq鉴定。负责季节性行为重编程的候选转录因子（TF）最终将通过克雷斯内的DNA基因组足迹来识别。该项目将通过致力于提高公众对帝王蝶栖息地保护工作需求的认识的外联活动，以及对对动物行为学、神经科学和生物信息学感兴趣的学生的研究培训，产生广泛的社会影响。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Many animals change their behavior in response to seasonal changes in the environment. The molecular nature of the changes that occur in the brain to alter behavior in a seasonal manner remains poorly understood. This project will examine epigenetic changes, i.e. changes in external modifications to DNA, that turn behavior-regulating genes on or off in a season-dependent manner. The work will be carried out using behavioral approaches and DNA sequencing of the genome of the long-distance migratory monarch butterfly, Danaus plexippus. The monarch exhibits extreme seasonal behavioral changes at the individual level in response to changing daylength and temperature. Migratory monarch butterflies accomplish an extraordinary journey of 2,000 miles from the United States to their overwintering sites in Mexico by flying southward in the fall. In the spring, migratory butterflies flip their flight orientation northward and return to the United States. This project will reveal seasonal epigenetic changes to the genome in the brains of these seasonal forms. These findings will provide insight into the molecular mechanisms underlying seasonal migration and the production of distinct seasonal flight orientations, and may be applicable to other migratory species. They could also have implications for conservation strategies to help preserve the iconic monarch migration, a spectacular yet threatened biological phenomenon. The project will provide valuable research training for students interested in animal behavior, neuroscience, and bioinformatics, including students from groups underrepresented in STEM fields. The researchers will also develop outreach activities devoted to increase public awareness for the need of monarch habitat conservation efforts.Seasonal behavioral adaptations are key to the ecological success of many animals. The behavioral plasticity observed in individuals in response to seasonal changes in the environment strongly suggests that epigenetics play a crucial role in shaping seasonal behavior. However, the epigenetic changes that link brain function to seasonal regulation of behavior remain largely unknown. This project will leverage the remarkable seasonal plasticity of monarch butterfly migratory behavior in response to seasonal changes in the environment (daylength, temperature) to delineate the genome-wide epigenetic architecture in the brain that underlies seasonal migratory behavior and flight orientation. The goal of the project is to identify active cis-regulatory elements (CREs) and putative transcription factors (TFs) that mediate differential gene expression in the brains of non-migrants, fall migrants and spring remigrants. The researchers will use fall migrants and fall migrants reprogrammed into spring remigrants in controlled conditions and a combination of next-generation sequencing technologies. Genes differentially expressed in the brains of these seasonal forms will be identified by RNA-seq, and open genomic regulatory regions and CREs that mediate this differential expression will be identified by ATAC-seq and ChIP-seq of histone marks. Candidate transcription factors (TFs) responsible for the seasonal behavioral reprogramming will ultimately be identified through DNA genomic footprinting within CREs. The project will have broad societal impacts through outreach activities devoted to increase public awareness for the need of monarch habitat conservation efforts, and research training of students interested in animal behavior, neuroscience, and bioinformatics.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.