Molecular and Cellular Mechanisms of Wound Repair and Morphogenesis

描述（由申请人提供）：用于修补单细胞膜撕裂的伤口修复机制和用于恢复多细胞组织伤口上皮完整性的伤口修复机制在很大程度上不同的规模上运作，但两者都对生存至关重要，并涉及一系列古老且高度保守的过程。因此，细胞和组织修复具有基本的细胞生物学兴趣和显著的临床相关性。本提案的总体目标是了解整个生物体体内环境中细胞和组织伤口修复的生物学基础。我们特别感兴趣的协调调节的肌动蛋白/微管细胞骨架和在这些过程中的肌动蛋白成核因子的作用。本研究提出了在果蝇伤口修复的机制，以利用其顺从性的现场成像与其高超的遗传tractability不提供在目前的伤口愈合模型。我们最近在果蝇合胞体胚胎中开发了一种单细胞伤口愈合模型，该模型沿着后期胚胎的多细胞组织伤口愈合模型，使得可以容易地比较野生型与候选伤口基因突变体胚胎的修复，并且使得可以筛选这些修复过程中的新的遗传参与者。本提案的具体目标是使用组合的分子、遗传和细胞生物学方法：1）检查肌动蛋白和微管细胞骨架在单细胞和多细胞组织创伤修复中的作用; 2）表征Rho 1 GTdR作为两种创伤修复过程的调节剂的功能;和3）鉴定两种修复过程的组分/机制和调节途径。我们的长期目标是精确地了解调节这些不同规模的伤口修复过程的参与者和事件。与伤口修复相关的形态学运动与正常形态发生事件有许多相似之处。因此，我们在这里学习的属性将影响我们对正常形态发生基础的基本生物事件和规则的理解。我们的研究也将在许多疾病的情况下，除了简单的皮肤修复的基本临床意义，并预计提供洞察力，可以指导进一步设计组织修复治疗，以提高愈合速度和/或防止疤痕，以及组织工程中心重建组织。 公共卫生相关性：生物体修复伤口的能力是基本的生存机制。人体会受到多细胞组织（如皮肤）和单细胞（如肌肉细胞）的损伤，必须能够快速修复这两种类型的损伤，以防止感染并恢复功能。拟议的研究使用苍蝇胚胎作为模型生物，以确定伤口修复的精确细节，并将其与正常发育过程进行比较。我们的研究结果可以很容易地外推到脊椎动物模型，并将有助于设计新的伤口修复疗法，可以加速愈合过程和/或防止过度疤痕。

DESCRIPTION (provided by applicant): The wound repair mechanisms used to mend a tear in the membrane of a single cell and those that restore epithelial integrity to multicellular tissue wounds operate on massively different scales, but both are critical for survival and involve a series of ancient and highly conserved processes. Cell and tissue repair is thus of both fundamental cell biology interest and significant clinical relevance. The general aim of this proposal is to understand the biological basis of both cell and tissue wound repair within the in vivo context of a whole organism. We are particularly interested in the coordinated regulation of the actin/microtubule cytoskeletons and in the role of actin nucleation factors in these processes. This study proposes to investigate the mechanisms of wound repair in Drosophila in order to utilize its amenability for live imaging in concert with its superb genetic tractability not available in current wound healing models. We have recently developed a single cell wound healing model in Drosophila syncytial embryos that along with the multicellular tissue wound healing model of later staged embryos allows easy comparison of repair in wildtype versus embryos mutant for candidate wound genes, and that makes it possible to screen for novel genetic players in these repair processes. The specific aims of this proposal are to use combined molecular, genetic and cell biological approaches to: 1) examine the roles of the actin and microtubule cytoskeletons in single cell and multicellular tissue wound repair; 2) characterize the functions of the Rho1 GTPase as a regulator of both wound repair processes; and 3) identify the components/machineries and regulatory pathways of both repair processes. Our long-term goal is to understand precisely the players and events that regulate these differently scaled wound repair processes. The morphological movements associated with wound repair share many similarities with normal morphogenetic events. Thus, the properties we learn here will impact our understanding of the basic biological events and regulations that underlie normal morphogenesis. Our studies will also be of fundamental clinical significance in many disease situations besides simply that of skin repair and is expected to provide insight that may guide further design of tissue repair therapies to enhance healing speed and/or prevent scarring, as well as for tissue engineering central to reconstructing tissues. PUBLIC HEALTH RELEVANCE: The capacity of an organism to repair a wound is a basic survival mechanism. The human body is subject to injuries to both multicellular tissues such as the skin, and to single cells such as muscle cells, and must be able to rapidly repair both types of damage to prevent infection and to restore function. The proposed studies use the fly embryo as a model organism in which to define the precise details of wound repair and compare that to normal developmental processes. Our findings can be easily extrapolated to vertebrate models, and will be useful in the design of new wound repair therapies that may speed the healing process and/or prevent excessive scarring.