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：
9103364
负责人：
Peter Andolfatto
金额：
$ 44.07万
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 2020-04-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9103364
关键词：
Adult Affect Animal Model Animals Biological Assay Body part Cells Collection Complex DNA Data Development Developmental Biology Dissection Drosophila melanogaster Enhancers Evolution Exhibits Female Figs - dietary Gene Mutation Genes Genetic Genetic Techniques 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 Text Tissues Transgenic Organisms Translating Untranslated RNA Up-Regulation Variant Work arm base differential expression genetic element genetic signature genetic variant genome wide association study male member novel overexpression physical property pleiotropism programs public health relevance reproductive research study 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）这项研究的目标是剖析快速进化的复杂性状背后的致病基因和突变，并了解该性状进化的限制本质，这样的努力需要一个实验系统，在该系统中，在短时间内发生剧烈的变化。果蝇物种组中的后叶是最近衍生的雄性生殖器结构特征，该结构对于交配至关重要，该结构在该组的四个物种中进化出了显着不同的形态。在过去的两百万年里，我们的初步工作记录了编码幼虫后螺旋的高度保守的基因调控网络（GRN）在成虫后叶中产生新的表型变异的明显的共同选择和重新部署。我们开发的机制将允许快速进化的肺叶发生变化，同时保持气门结构不变，我们已经证明了痘神经基因（poxn）是该GRN的成员之一。相对于果蝇，在拟果蝇中，poxn 的表达呈不同程度上调，并且在果蝇中的过度表达会导致果蝇的叶增大，如在拟果蝇中观察到的那样。此外，我们还发现，拟果蝇中 poxn 的上调是由以下因素引起的。基因内包含的后叶特异性增强子的序列分歧使用群体遗传方法来检测自然选择，我们已经确定了与后叶增强子一致的选择特征。在这里，我们建议采用基因组（即 RNA-seq、群体基因组学）和分子遗传学技术（即转基因表达和互补测定）来识别导致物种间后叶大小和形状差异的其他致病基因和突变。 D. melanogaster 物种组（目标 1 和 2）。有了大量此类分子变化，我们将研究后叶的增选节点在其叶功能上是如何分化的。不改变螺旋结构（目标 3）。