Seq-ing the etiology of birth defects in a new frog model, Lepidobatrachus laevis

测序新青蛙模型 Lepidobtrachus laevis 中出生缺陷的病因

基本信息

批准号：
8771976
负责人：
Nanette M Nascone-Yoder
金额：
$ 22.73万
依托单位：
NORTH CAROLINA STATE UNIVERSITY RALEIGH
依托单位国家：
美国
项目类别：
财政年份：
2014
资助国家：
美国
起止时间：
2014-09-01 至 2016-08-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8771976
关键词：
Amphibia Anatomy Animal Model Biocompatible Materials Biological Biological Assay Biological Markers Caliber Candidate Disease Gene Cell physiology Child Clinical Complex Congenital Abnormality Contralateral Defect Deformity Development Developmental Biology Developmental Process Disease Embryo Embryonic Development Embryonic Heart Etiology Event Excision Fertilization Gastrointestinal tract structure Gene Expression Gene Expression Profile Genomics Goals Handedness Heart Homologous Gene Hour Human Human Biology Individual Infant Infant Mortality Knowledge Laboratories Larva Lead Left Life Mammals Measures Methodology Modeling Molecular Morbidity - disease rate Morphogenesis Oocytes Organ Organism Organogenesis Phase Rana Reagent Research Resolution Resources Risk Shapes Side South American Staging Structural Congenital Anomalies Tadpoles Testing Therapeutic Intervention Tissues Transcript Tube United States Work Xenopus oocyte animal model development blastocyst body system genetic variant genome-wide human disease in vivo innovation malformation mortality novel patient population public health relevance response transcriptome sequencing

项目摘要

DESCRIPTION (provided by applicant): The causes of most human birth defects are unknown. Structural defects in the heart and digestive tract are frequently found in association with abnormal left-right asymmetries in other organ systems, suggesting that such deformities may result from perturbed laterality, yet the developmental processes that form asymmetries within individual organs remain elusive. The long term goal is to determine the morphogenetic mechanisms that control the development of anatomical left-right asymmetry. The objective of this exploratory R21 application is to gain a comprehensive view of the left-right asymmetric molecular differences within the embryonic heart and gut tubes as they undergo asymmetric "looping", a fundamental organogenesis event that orients the most crucial anatomical asymmetries. To accomplish this objective, the unique embryological features of a novel model amphibian, Lepidobatrachus laevis, will be developed and exploited. Lepidobatrachus has massive embryos that facilitate precise excision of the left and right halves of the early heart an gut during looping, enabling the heretofore infeasible approach of left-right transcriptome profiling during a key phase of asymmetric morphogenesis. The central hypothesis is that identifying transcripts that are differentially expressed between the contralateral halves of looping organs will identify new molecules that control left-right asymmetric morphogenesis. This hypothesis will be tested via two specific aims: 1) Identify transcripts that are differentialy expressed between the left and right sides of the looping heart and gut tubes; and 2) Validate the biological relevance of left- or right-enriched transcripts for asymmetric organ morphogenesis. Under Aim 1, an RNAseq approach (supported by a draft Lepidobatrachus transcriptome already constructed by the PI) will be used to complete genome-wide expression analyses that will reveal unilaterally-enriched transcripts associated with the formation of key anatomical asymmetries. Under Aim 2, the proven ability to precisely target exogenous reagents to the left or right side of developing organs in amphibians, and the unprecedented subcellular resolution of developing organ asymmetries provided by the sizeable Lepidobatrachus, will be used to authenticate the in vivo function of select unilaterally-enriched transcripts in asymmetric morphogenesis. The approach is innovative because it takes advantage of the distinctive attributes of a unique non-model organism to understand one of the key unanswered questions in the field of left-right development: what are the mechanism(s) by which developing organs acquire critical left- right asymmetric anatomical features? The proposed research is significant because it is expected to immediately accelerate our understanding of the etiology of some of the most common birth defects by identifying new classes of molecules, and new cellular processes, which shape the fundamental left-right asymmetry of the heart and gut.

描述（由申请人提供）：大多数人类出生缺陷的原因尚不清楚。心脏和消化道的结构缺陷经常与其他器官系统中异常的左右不对称相关，这表明这种畸形可能是由于侧向扰动造成的，但单个器官内形成不对称的发育过程仍然难以捉摸。长期目标是确定控制解剖学左右不对称发展的形态发生机制。这一探索性 R21 应用的目的是全面了解胚胎心脏和肠管在经历不对称“循环”时的左右不对称分子差异，这是一种基本的器官发生事件，定向最关键的解剖不对称性。为了实现这一目标，将开发和利用一种新型两栖动物模型——Lepidobatrachus laevis 的独特胚胎学特征。鳞蝠具有巨大的胚胎，有助于在成环过程中精确切除早期心脏和肠道的左右半部，从而在不对称形态发生的关键阶段实现迄今为止不可行的左右转录组分析方法。中心假设是，识别环状器官对侧半部之间差异表达的转录本将识别控制左右不对称形态发生的新分子。该假设将通过两个具体目标进行测试：1）识别在循环心脏和肠管的左侧和右侧之间差异表达的转录本； 2) 验证左侧或右侧富集转录本与不对称器官形态发生的生物学相关性。在目标 1 下，RNAseq 方法（由 PI 已构建的 Lepidobtrachus 转录组草案支持）将用于完成全基因组表达分析，该分析将揭示与关键解剖不对称形成相关的单侧富集转录本。在目标 2 下，已证明能够将外源试剂精确定位到两栖动物发育中器官的左侧或右侧，以及大型鳞蜥蜴提供的发育中器官不对称性的前所未有的亚细胞分辨率，将用于验证选择的体内功能不对称单方面富集转录本形态发生。该方法具有创新性，因为它利用了独特的非模型生物体的独特属性来理解左右发展领域中尚未解答的关键问题之一：发育中的器官获得关键左发展的机制是什么- 右侧不对称的解剖特征？这项拟议的研究意义重大，因为它有望通过识别新类别的分子和新的细胞过程，立即加速我们对一些最常见出生缺陷病因的理解，这些分子和细胞过程塑造了心脏和肠道的基本左右不对称性。。