Mechanisms of developmental buffering

项目摘要/摘要： 这项提议的长期目标是了解遗传缓冲，或一些个体如何克服 有害基因突变的影响。我们生成了一个斑马鱼缓冲模型，以便理解 本应患病的人是如何以某种方式过上不受影响的健康生活的。在我们的模型中， 我们通过选择性繁殖产生了两种头部发育截然不同的斑马鱼。 骨骼对同样有害的基因突变的反应。在一种菌株中，这种突变会导致严重的、致命的 骨骼缺陷。与此同时，另一种菌株对这种突变有显著的缓冲作用。缓冲的鱼 发育出基本正常的头骨，存活下来成为有生育能力的成体。我们将这些菌株与 了解一些鱼身上存在的自然缓冲机制，可能在一些人类身上也是如此。我们 假设缓冲是由于调节发育过程以恢复平衡的因素造成的。为 例如，在Aim1中，我们将确定如何拒绝与突变基因相反的DNA序列。 在目标2中，我们检查DNA中与突变基因执行相同功能的因子是如何编码的 可以调大音量。在目标3中，我们将确定不一定涉及 DNA序列可以缓冲有害突变。这三个具体目标测试了相互作用机制 共同发挥作用，缓冲发展。我们设计了实验来解决这些目标，使用最先进的技术 基因组编辑和测序，彩色细胞和组织标记，定量测量 大量的鱼类骨骼和严格的统计分析。我们在这里建议研究的机制 存在于许多发育系统和生物体中，因此很可能适用于广泛的 测距设置。这种缓冲机制的研究可能导致新的治疗方法，缓冲 未来可能会操纵机制来管理疾病症状。这项工作还将导致 更好地了解使根据基因序列预测遗传病变得困难的因素。因此， 这一系列研究有可能为包括遗传病在内的医疗实践提供信息并加以改进。 管理、疾病诊断和咨询，完全属于NIDCR改进的使命 通过研究促进牙科、口腔和颅面的健康。

PROJECT SUMMARY/ABSTRACT: The long-term objective of this proposal is to understand genetic buffering, or how some individuals overcome the effects of a harmful genetic mutation. We generated a zebrafish model of buffering in order to understand how individuals who should have gotten sick are somehow able to live unaffected healthy lives. In our model, we used selective breeding to generate two strains of zebrafish that develop dramatically different head skeletons in response to the same harmful genetic mutation. In one strain, the mutation causes severe, lethal skeletal defects. Meanwhile, the other strain is remarkably buffered against the mutation. The buffered fish develop essentially normal head skeletons, surviving to be fertile, viable adults. We compare these strains to understand the natural buffering mechanisms that are present in some fish, and likely in some humans too. We hypothesize that buffering is due to factors that tune developmental processes to restore balance. For example, in Aim1 we will determine how DNA sequences which oppose the mutant gene can be turned down. In Aim 2 we examine how factors encoded in the DNA which perform the same function as the mutant gene can be turned up. In Aim 3 we will determine how changes that do not necessarily involve alterations in the DNA sequence can buffer the harmful mutation. These three specific aims test how interacting mechanisms function together to buffer development. We designed experiments to address these aims using state of the art methods like genome editing and sequencing, colorful cell and tissue labeling, quantitative measurements of large numbers of fish skeletons, and rigorous statistical analyses. The mechanisms we propose to study here are present in many developmental systems and organisms and therefore will likely be applicable in wide- ranging settings. This study of buffering mechanisms could lead to novel therapeutic approaches, buffering mechanisms might be manipulated in the future to manage disease symptoms. This work will also lead to a better understanding of the factors that make predicting genetic disease from gene sequences difficult. Thus, this line of research will potentially inform and improve medical practices, including genetic disease management, disease diagnosis, and counseling, falling squarely within the mission of the NIDCR to improve dental, oral and craniofacial health through research.