Collaborative Research: Insulin and Limb-Patterning Pathway Activities in the Horns of Beetles: An Integrative Study of the Mechanisms of Allometry, Dimorphism, Branching & Cur

几乎所有昆虫形态性状的表达都对营养敏感，但对性状生长与营养耦合的遗传机制几乎一无所知。一个极端的例子发生在圣甲虫的“角”上。在同一物种中，甲虫角的大小和形状可以根据幼虫的营养状况发生巨大变化。有角的甲虫包括一些今天活着的最壮观和最奇怪的生物。这些角的大小（相对于携带它们的甲虫的大小）甚至可以使最极端的有蹄类动物的角相形见绌，角形式的多样性令人惊叹。因此，甲虫角是具有已知功能意义的显著结构。一个多世纪以来，人们对这些动物的兴趣和观察以及最近的许多行为研究，为角发育的研究提供了丰富的生态背景。这项研究项目的长期目标是了解生理、遗传和发育与环境相互作用的方式，从而产生动物形态的多样性。该项目的目的是确定产生甲虫角表达变异的机制。具体目的是确定：(1)胰岛素受体途径在多大程度上调节角甲虫对营养反应的性状生长，(2)胰岛素受体途径和肢体模式途径调节角表达的雄性二态性和性别二态性，以及(3)肢体模式途径在不同角形态的甲虫中指定角形状。该奖项的结果将提供重要的新信息，说明如何修改昆虫的发育机制，以产生具有生物学意义的——甚至是惊人的——动物形态变异。通过这种方式，这项研究将解决生物学中基本和长期存在的问题，例如：新颖和复杂的形态结构是如何产生的？这些特征是如何被修改以产生动物形态的多样性的？这项研究合作的一个核心目标是在发育、遗传学和进化方面交叉培训年轻科学家。参与该项目的研究生和本科生都将在PI的两个实验室中度过时间，并将接受发育和遗传方法方面的培训。这项研究的许多方面都适合独立的本科生项目，pi致力于在研究过程的各个方面训练学生，包括写作和在地方和国家会议上展示结果。这两个学院在培训妇女和少数民族从事科学方面都有出色的记录。这个项目的两个重点物种是非常大的犀牛甲虫，是全世界博物馆和教室的最爱，是一系列教育项目的完美选择。该项目将利用这些动物进行各种教育/推广活动，包括参观当地学校的教室，支持华盛顿州立大学昆虫博物馆，并协助新建蒙大拿州昆虫动物园。

The expression of virtually all insect morphological traits is sensitive to nutrition, yet almost nothing is known about the genetic mechanisms that couple trait growth with nutrition. An extreme example occurs in the 'horns' of scarab beetles. Within a single species, beetle horns can vary tremendously in size and shape dependent upon larval nutrition. Beetles with horns include some of the most magnificent and bizarre organisms alive today. The sizes of these horns (relative to the sizes of the beetles that bear them) can dwarf even the most extreme antlers of ungulates, and the diversity of horn forms is breathtaking. Thus, beetle horns are conspicuous structures with known functional significance. With more than a century of interest and observation of these animals and many recent behavioral studies, there is a rich ecological context for the study of horn development.The long-term goal of this research project is to understand the ways that physiology, genetics, and development interact with the environment to generate diversity in animal forms. The objective of this project is to determine the mechanisms responsible for generating variation in the expression of beetle horns. The specific aims are to determine the extent to which (1) the insulin receptor pathway adjusts trait growth in response to nutrition in horned beetles, (2) the insulin receptor pathway and the limb-patterning pathway regulate male dimorphism and sexual dimorphism in horn expression, and (3) the limb-patterning pathway specifies horn shape in beetles with different horn morphologies. The results of this award will provide important new information about how the mechanisms of insect development may be modified to generate biologically meaningful - even spectacular - variation in animal form. In this way, this research will address fundamental and long-standing questions in biology such as: How do novel and complex morphological structures arise? And how are these traits modified to generate diversity in animal form?A core objective of this research collaboration is the cross-training of young scientists in development, genetics, and evolution. Both graduate and undergraduate students involved with this project will spend time in both of the PI's laboratories and will be trained in developmental and genetic methods alike. Numerous aspects of this study lend themselves to independent undergraduate student projects, and the PIs are committed to training students in all aspects of the research process including writing and presenting results at local and national meetings. Both PIs have excellent track records in the training of women and minorities in the sciences. Two of the focal species in this project are very large rhinoceros beetles and worldwide favorites of museums and classrooms, and are perfect for a range of educational programs. This project will use these animals in a variety of educational/outreach activities including visiting local school classrooms, supporting the Washington State University Insect Museum, and aiding with a new Montana insect zoo.