Genetic Analysis of Inner Ear Development in Xenopus tropicalis

热带爪蟾内耳发育的遗传分析

基本信息

批准号：
8509655
负责人：
Richard M Harland
金额：
$ 27.3万
依托单位：
UNIVERSITY OF CALIFORNIA BERKELEY
依托单位国家：
美国
项目类别：
财政年份：
2011
资助国家：
美国
起止时间：
2011-08-01 至 2016-07-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8509655
关键词：
ATP-Binding Cassette Transporters Acceleration Adaptor Signaling Protein Address Affect Aging Alleles Amphibia Animal Model Animals Auditory Behavior Behavioral Candidate Disease Gene Cell Lineage Cells Chemicals Clinical Data Defect Development Disease Ear Embryology Equilibrium Esthesia Event Exons Family Fishes Functional disorder Future Genes Genetic Genetic Screening Genome Grant Hearing Human Individual Inherited Labyrinth Lead Lesion Link Mammals Maps Melanophores Methods Molecular Morphogenesis Morphology Multi-Drug Resistance Mus Mutagenesis Mutant Strains Mice Mutation Nature Noise Nonsense Codon Otic Placodes Otic Vesicle Pathway interactions Pattern Pharmaceutical Preparations Phenotype Pigmentation physiologic function Process Proteins Rana Research Resolution Role Sensory Sequence Analysis Signal Transduction Sorting - Cell Movement Staging Structure Swimming Synteny System Tadpoles Tissues Transplantation Vertebrates Vesicle Xenopus base comparative deafness equilibration disorder gene function genetic analysis hearing impairment high risk insight mammalian genome member mutant novel otoconia positional cloning response

项目摘要

DESCRIPTION (provided by applicant): Deficits in hearing or balance are common, and result from both developmental and environmental causes. In order to understand normal inner ear development, we will use the genetically tractable frog, Xenopus tropicalis, to investigate the genetic network underlying ear development. The structure and development of the inner ear shows conserved features among the vertebrates, and the development of the ear of the tetrapod is very similar to that of mammals. The relevant stages of ear development can be observed in the optically clear tadpole, making this animal ideal for genetic screens for ear mutants. Furthermore, defects in ear development lead to abnormal swimming behavior and loss of the righting response, so that defects that may not be anatomically obvious can also be scored. In response to PA-06-365, "Cell Lineage and Developmental Studies in Hearing and Balance" we have addressed the stated need for "more comprehensive representation of model organisms systems" to study ear development. We propose to advance our understanding of ear development by examining otic vesicle development in the tetrapod Xenopus tropicalis, an amphibian whose inner ear development is well-conserved with mammals. In a small-scale forward genetic screen using Xenopus tropicalis we have recovered mutants that disrupt ear morphology, otolith formation, and balancing/swimming behavior. We have isolated the affected gene in two of these that affect otoconial development and otocyst size. Thus we have shown that it is possible to screen for and recover mutants, analyze the phenotype, and map and clone the affected genes. The genome of X. tropicalis shows considerable structural similarity and synteny with mammalian genomes, with no sign of additional whole genome duplications, so we are confident that we can identify recessive mutants in a variety of genes which show conserved functions with the mammals. With recent improvements in the genome assembly and annotation, and technical advances in exon capture and high throughput sequence analysis, we are confident that other mutations can be rapidly mapped, and the affected genes isolated. In the next grant period, we propose to characterize additional mutant alleles by positional cloning, and link mutant phenotypes with the underlying molecular and cellular defects. We combine molecular approaches with classical embryological transplantations to understand the cel autonomy of mutants, and the signaling and responding tissues that interact to produce the functioning ear.

描述（由申请人提供）：听力或平衡能力缺陷很常见，是由发育和环境原因造成的。为了了解正常的内耳发育，我们将使用遗传上易驯化的青蛙热带爪蟾来研究耳朵发育背后的遗传网络。内耳的结构和发育在脊椎动物中表现出保守的特征，四足动物的耳朵的发育与哺乳动物非常相似。可以在光学透明的蝌蚪中观察到耳朵发育的相关阶段，使这种动物成为耳朵突变体遗传筛选的理想动物。此外，耳朵发育缺陷会导致游泳行为异常和翻正反应丧失，因此也可以对解剖学上不明显的缺陷进行评分。为了响应 PA-06-365“听力和平衡的细胞谱系和发育研究”，我们解决了“更全面地表示模型生物体系统”以研究耳朵发育的需求。我们建议通过检查四足动物热带爪蟾的耳囊发育来增进我们对耳朵发育的理解，热带爪蟾是一种两栖动物，其内耳发育与哺乳动物一样保存完好。在使用热带爪蟾的小规模正向遗传筛选中，我们发现了破坏耳朵形态、耳石形成和平衡/游泳行为的突变体。我们已经在其中两个影响耳圆锥发育和耳囊大小的基因中分离出了受影响的基因。因此，我们已经证明，筛选和恢复突变体、分析表型以及绘制和克隆受影响的基因是可能的。热带假丝酵母的基因组与哺乳动物基因组显示出相当大的结构相似性和同线性，没有额外的全基因组重复的迹象，因此我们有信心能够在多种基因中识别出与哺乳动物具有保守功能的隐性突变体。随着基因组组装和注释的最新改进，以及外显子捕获和高通量序列分析技术的进步，我们相信可以快速绘制其他突变图谱，并分离受影响的基因。在下一个资助期内，我们建议通过定位克隆来表征其他突变等位基因，并将突变表型与潜在的分子和细胞缺陷联系起来。我们将分子方法与经典胚胎移植相结合，以了解突变体的细胞自主性，以及相互作用产生功能性耳朵的信号传导和响应组织。