The evolution of a co-opted gene-regulatory network underlying a rapidly evolving morphological trait

快速进化的形态特征背后的增选基因调控网络的进化

基本信息

批准号：
9477041
负责人：
Peter Andolfatto
金额：
$ 42.39万
依托单位：
PRINCETON UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2016
资助国家：
美国
起止时间：
2016-07-04 至 2019-04-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9477041
关键词：
Adult Affect Animal Model Animals Biological Assay Body part Cells Collection Color Complement Complex DNA Data Development Developmental Biology Dissection Drosophila melanogaster Enhancers Evolution Exhibits Female Foundations Gene Mutation Genes Genetic Genetic Techniques Genetic Transcription Genitalia Genome Genomics Goals Hand Health Human Individual Individuality Investigation Left Lobe Male Genital Organs Maps Methods Modeling Molecular Molecular Genetics Morphology Mutation Natural Selections Nature Organism Outcome Partner in relationship Pattern Phenotype Plants Population Population Genetics Race Regulator Genes Research Shapes Signal Pathway Source Structural Genes Structure System Taxonomy Text Time Tissues Transgenic Organisms Translating Untranslated RNA Up-Regulation Variant Work arm base differential expression experimental study genetic element genetic signature genetic variant genome wide association study male member novel overexpression physical property pleiotropism programs public health relevance reproductive response stem trait transcription factor transcriptome transcriptome sequencing treatment strategy

项目摘要

DESCRIPTION (provided by applicant) The goal of this research is to dissect the causative genes and mutations underlying a rapidly evolving complex trait and to understand the nature of constraints on the evolution of this trait. Such an endeavor requires an experimental system in which drastic changes occur over short evolutionary timeframes in species that can be easily manipulated genetically. The posterior lobe in the Drosophila melanogaster species group is a recently-derived structural feature of male genitalia important in mating. The structure has evolved strikingly different morphology in each of the four species of this group over the past two million years. Our preliminary work has documented the apparent co-option and re-deployment of a highly conserved gene regulatory network (GRN) encoding the larval posterior spiracle in creating novel phenotypic variation in the adult posterior lobe. This finding stimulates us to hypothesize mechanisms that would allow the rapidly evolving lobe to change while leaving the spiracle structure unaltered. Among the members of this GRN is the gene pox neuro (poxn) which we have shown is divergently upregulated in D. simulans relative to D. melanogaster and that over-expression in D. melanogaster leads to enlargement of the lobe as observed in D. simulans. Additionally, we have shown that the upregulation of poxn in D. simulans is caused by sequence divergence in a posterior lobe-specific enhancer contained within the gene. Using a population genetic method to detect natural selection, we have identified a signature of selection that coincides with the posterior lobe enhancer of poxn. Here, we propose to employ genomic (i.e. RNA-seq, population genomics) and molecular genetic techniques (i.e. transgenic expression and complementation assays) to identify other causative genes and mutations responsible for differences in posterior lobe size and shape among species of the D. melanogaster species group (Aims 1 and 2). With a large collection of such molecular changes in hand, we will examine how co-opted nodes of the posterior lobe have diverged in their lobe functions without altering the spiracle structure (Aim 3).

描述（由申请人提供）这项研究的目的是剖析快速发展的复杂性状的严重基因和突变，并了解对该特征进化的约束的性质。这样的努力需要一个实验系统，在该系统中，在物种中短暂的进化时间表上发生了巨大的变化，这些变化很容易被一般操纵。果蝇果蝇中的后叶是近来衍生的男性生殖器在交配中很重要的结构特征。在过去的两百万年中，该群体的四个物种中的每个物种中的每个物种都发展出明显不同的形态。我们的初步工作记录了高度保守的基因调节网络（GRN）的明显合作和重新部署，该基因调节网络（GRN）编码了幼虫后螺旋液，从而在成人后叶创建了新型的表型变化。这一发现刺激了我们假设机制，这将使迅速发展的叶变化，同时使螺旋结构不变。在该GRN的成员中，我们已经显示的基因痘神经（POXN）在D. simulans中与D. melanogaster相对于D. melanogaster进行了分歧，并且在D. melanogaster中的过表达导致叶片在D. simulans中观察到的叶子扩展。此外，我们已经表明，D。simulans中POXN的上调是由基因内包含的后叶特异性增强子中的序列发散引起的。使用种群遗传方法检测自然选择，我们已经确定了与POXN后叶增强子相吻合的选择签名。在这里，我们建议员工基因组（即RNA-SEQ，种群基因组学）和分子遗传技术（即转基因表达和完成分析），以鉴定其他严重的基因和突变，这些基因和突变导致D.黑色素果种类群的后叶大小和形状差异（目标1和2）。随着大量这种分子变化的收集，我们将检查后叶的配置节点如何在其叶函数中差异，而不会改变螺旋液结构（AIM 3）。