SG: Evolutionary history and contemporary function of alternative supergene haplotypes

甚至在DNA的结构被描述之前，生物学家西奥多西乌斯·多布赞斯基就预测，生物体的复杂特征应该由一组密切相关的基因控制。他把这些称为“共适应基因复合体”，并假设它们应该作为一个单位传递给后代。这些单位将在下一代保持某些有益的遗传变异组合不变。如今，基因组测序技术可以研究共适应基因复合体(又称超基因)是否真的控制着复杂的特征。激发人类好奇心的一个特征就是社会组织性。合作行为是如何在社会有机体的DNA中编码的？此前的研究发现，蚂蚁的一项复杂的社会特征中存在一个与变异相关的大型表观基因。这个表观基因包含600多个基因单位，这些基因作为一个单位传递给后代。相比之下，大多数基因组会从一代传到下一代，以确保后代从每个父母那里继承不同的基因变异。在多个蚁类物种中，由一只蚁后及其后代组成的群体中的个体具有这种超级基因的一种变体。来自包含多个蜂王的蜂群的个体具有不同的变体。这个项目的目标是了解这些超级基因是如何在物种群体中出现和持续存在的，它们是如何工作的，以及基因是如何塑造社会行为的。这个项目将是理解超基因形成的方式和原因的重要一步，也是发展基因和社会行为之间的联系的重要一步。这个项目还将为本科生提供研究培训的机会，并向K-12学生介绍社会性昆虫的研究。PI和共同PI最近发现了两种蚂蚁物种，每种蚂蚁都携带三种不同的超级基因变体。这个项目将利用三个单倍型共同出现的每个物种的一个种群。利用这些群体，研究人员将表征上基因上不同单倍型之间的差异，并将这种差异与功能差异联系起来。特别是，表型和适合度的差异将通过一系列交配和育苗实验来研究。这些实验将包括在每个物种中具有每种可能基因的女王。此外，将通过高密度连锁图谱和全基因组测序来评估可供选择的单倍型之间的基因顺序、重组率和抑制重组区，以重建它们的进化史。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Even before the structure of DNA was described, biologist Theodosius Dobzhansky predicted that complex traits of organisms should be controlled by groups of closely related genes. He called these 'coadapted gene complexes' and hypothesized they should be passed on to offspring as a unit. These units would keep certain beneficial combinations of genetic variation intact in the next generation. Today, genome sequencing technology allows research into whether coadapted gene complexes, also called 'supergenes', indeed control complex traits. One such trait that has inspired curiosity in humans is social organization. How are cooperative behaviors encoded in the DNA of social organisms? Previous research found a large supergene associated with variation in a complex social trait in ants. This supergene contains units of more than 600 genes that are passed together as a unit to offspring. By contrast, most of the genome is shuffled from one generation to the next to ensure that offspring inherit different genetic variation from each parent. In multiple Formica ant species, individuals from colonies that consist of a single queen and her offspring have one variant of this supergene. Individuals from colonies that contain multiple queens have a different variant. The goal of this project is to learn how these supergenes appear and persist in groups of species, how they work, and how genes shape social behavior. This project will be an important step in understanding how and why supergenes form, and also in developing the link between genes and social behaviors. This project will also provide opportunities for undergraduate research training and introduce K-12 students to the study of social insects.The PI and co-PI have recently identified two ant species that each carry three alternative variants of the supergene. This project will take advantage of one population of each species where three haplotypes co-occur. Using these populations, the researchers will characterize the variation among alternative haplotypes at the supergene and link that variation to functional differences. In particular, differences in phenotype and fitness will be investigated with a series of mating and brood rearing experiments. The experiments will include queens with each possible genotype in each species. Additionally, the gene order, recombination rates, and zones of suppressed recombination between alternative haplotypes will be assessed through high density linkage mapping and whole genome sequencing, in order to reconstruct their evolutionary history.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.