Identifying enhancers with human-specific developmental functions

识别具有人类特异性发育功能的增强子

• 批准号: 8304962
• 负责人: James P Noonan
• 金额: $ 62.53万
• 依托单位: YALE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-08-01 至 2015-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8304962
• 关键词: Acceleration; Affinity Chromatography; Alzheimer' s Disease; Anterior; Behavioral; Binding; Binding Sites; Biochemical; Biological Assay; Brain; ChIP-seq; Clinic; Complement; Complementary DNA; Conserved Sequence; Coupled; Data; Data Set; Deposition; Development; Developmental Gene; Disease; E1A-associated p300 protein; EP300 gene; Elements; Embryo; Enhancers; Event; Evolution; Gel; Gene Expression Profile; Gene Expression Regulation; Gene Targeting; Genes; Genetic; Genome; Genomics; Goals; Health; Heart Diseases; Human; Human Biology; Human Development; Human Genome; In Situ Hybridization; In Vitro; Indium; Infection; LacZ Genes; Language; Light; Limb Development; Limb structure; Macaca mulatta; Malaria; Maps; Mass Spectrum Analysis; Measures; Metabolic; Methods; Mission; Modeling; Modification; Molecular; Molecular Profiling; Morphology; Multiple Sclerosis; Mus; Mutation; Orthologous Gene; Pan Genus; Pattern; Phenotype; Phylogenetic Analysis; Policies; Primates; Psychotic Disorders; Public Health; Publishing; Recording of previous events; Recruitment Activity; Regulatory Element; Relative (related person); Reporter; Reporter Genes; Research; Research Personnel; Research Proposals; Role; Skin Cancer; Source; Statistical Methods; Talents; Technology; Testing; Thumb structure; Time; Transgenic Mice; Transgenic Organisms; United States National Institutes of Health; Vocabulary; Walking; Wrist; base; brain size; embryo tissue; experimental analysis; gain of function; genetic analysis; genome database; genome sequencing; genome-wide; homologous recombination; human disease; improved; in vivo; insertion/deletion mutation; insight; mouse development; mouse genome; novel; positional cloning; postnatal; public health relevance; research study; spatiotemporal; stem; tool; trait; transcription factor; web site

DESCRIPTION (provided by applicant): As a species, we are distinguished from other primates by our capacity for language, our ability to walk upright, and our talent for inventing and using sophisticated tools. These traits originated in physical adaptations, such as increased brain size and changes in the morphology of the limbs, which required changes in development. Although it has long been thought that changes in gene regulation drove the evolution of uniquely human traits, in vivo evidence for human-specific developmental regulatory functions remains elusive. Moreover, despite intensive efforts to annotate functional elements in the genome, such as the ENCODE project, there is no parallel effort to annotate uniquely human cis-regulatory functions. The goal of this study is to identify and characterize developmental enhancers with human-specific functions in vivo and examine their role in human evolution. The aims of our proposal are based on extensive preliminary data. We have developed a novel computational approach to identify noncoding, potentially regulatory sequences that are highly conserved across vertebrate species, but that changed substantially during human evolution. Using a mouse transgenic enhancer assay, we have identified eight of these "human-accelerated" conserved noncoding sequences (HACNSs) that function as enhancers during development. Of particular relevance for the aims of this proposal, we have also shown that the most rapidly evolving element in our dataset, HACNS1, is a developmental enhancer that has gained a robust limb expression domain relative to the orthologous elements from chimpanzee and rhesus macaque. This domain includes the presumptive anterior wrist and proximal thumb. Here we will build on these previous studies to generate more sophisticated maps of human-specific sequence acceleration in noncoding elements, including transcription factor binding site data and ChIP-seq data generated by genome-wide efforts to annotate regulatory function. We will use these data in conjunction with computational and experimental filters, such as extreme evolutionary constraint and recruitment of p300, to predict enhancers and mouse transgenic technologies to identify and characterize enhancers with human-specific activities. We will use synthetic enhancers and biochemical approaches to determine how human-specific sequence change alters enhancer function. Finally, we will use a reverse genetic strategy to study the evolutionary relevance of the human-specific functional change in HACNS1, by using gene targeting to replace the mouse ortholog of HACNS1 with the human enhancer and evaluating the effect of this genetic change on mouse development. The results from these studies will complement and extend current efforts to functionally annotate the human genome and will begin to reveal the precise molecular evolutionary events that produced modern humans. PUBLIC HEALTH RELEVANCE: Understanding the genetic basis of human morphology and development is central to the public health mission of the NIH. Beyond the fundamental question of human origins, studying human evolutionary history is directly relevant to human health, as many common human diseases may in part be due to the effects of sequence changes that were advantageous early in our evolution but are now harmful. Evidence for this hypothesis stems from human and chimpanzee comparisons: many prevalent human diseases with a genetic component, including skin cancers, heart disease, malaria infection, Alzheimer disease, multiple sclerosis and major psychoses, appear to be uncommon, different or absent in chimpanzees. Our research may thus shed light on the genetic and evolutionary basis of diseases that are unique to our species.

描述（由申请人提供）：作为一个物种，我们与其他灵长类动物的区别在于我们的语言能力，直立行走的能力，以及发明和使用复杂工具的才能。这些特征源于身体适应，比如大脑体积的增大和四肢形态的变化，这些都需要在发育过程中发生变化。尽管长期以来人们一直认为基因调控的变化推动了人类独特特征的进化，但关于人类特异性发育调控功能的体内证据仍然难以捉摸。此外，尽管对基因组中的功能元件进行了大量的注释，如ENCODE项目，但还没有对人类独特的顺式调控功能进行相应的注释。本研究的目的是在体内鉴定和表征具有人类特异性功能的发育促进子，并研究它们在人类进化中的作用。我们建议的目标是以广泛的初步数据为基础的。我们已经开发了一种新的计算方法来识别非编码的，潜在的调控序列，这些序列在脊椎动物物种中高度保守，但在人类进化过程中发生了重大变化。通过小鼠转基因增强子实验，我们发现了8个“人类加速”的保守非编码序列（HACNSs），它们在发育过程中起着增强子的作用。与本提案的目的特别相关的是，我们还表明，我们的数据集中进化最快的元件HACNS1是一个发育增强子，相对于黑猩猩和恒河猴的同源元件，它已经获得了一个强大的肢体表达域。这个区域包括假定的手腕前部和拇指近端。在此，我们将以这些先前的研究为基础，在非编码元件中生成更复杂的人类特异性序列加速图谱，包括转录因子结合位点数据和通过全基因组努力注释调控功能生成的ChIP-seq数据。我们将使用这些数据结合计算和实验过滤器，如极端进化约束和p300的招募，来预测增强子和小鼠转基因技术，以识别和表征具有人类特异性活性的增强子。我们将使用合成增强子和生化方法来确定人类特异性序列变化如何改变增强子的功能。最后，我们将使用反向遗传策略研究HACNS1人类特异性功能变化的进化相关性，通过基因靶向将HACNS1的小鼠同源物替换为人类增强子，并评估这种遗传变化对小鼠发育的影响。这些研究的结果将补充和扩展目前对人类基因组进行功能注释的努力，并将开始揭示产生现代人类的精确分子进化事件。