MOLECULAR GENETIC ANALYSIS OF WOUND HEALING--DROSOPHILA

导致组织或组织完整性丧失的创伤构成伤口，并启动伤口愈合或修复过程。这一过程的关键特征包括立即实现组织内稳态，排斥微生物，并最终恢复正常的组织生理。人类的创伤和伤口愈合具有相当大的生物学意义和社会意义。出于有益的医学原因，伤口可能是意外发生的，可能是在愤怒中造成的，也可能是在手术过程中发生的。我们提出的这项工作的最终目标是了解伤口上皮反应的基本生物学，长期目标是为设计干预策略做出贡献，旨在加速愈合或防止过度瘢痕形成。许多脊椎动物，特别是哺乳动物，已经开发出用于研究创伤和伤口愈合的动物模型系统。因此，负责适当伤口愈合的分子参与者已经开始被识别。近年来，基因敲除和转基因小鼠技术已被应用于创伤愈合的研究。然而，哺乳动物模型系统只有在经过仔细的伦理考虑后才能用于创伤研究，这自然是耗时的，而且非常昂贵。此外，正向基因筛查本质上是不切实际的。在这里，我们建议采用果蝇独有的分子/遗传策略来研究创伤和伤口愈合的生物学。最近，我们使用机械和激光方法来消融果蝇胚胎的组织，发现这种消融之后是快速和强大的愈合。此外，我们还发现，由于肌球蛋白重链结构基因的缺陷，纯合子胚胎的愈合完全受到抑制。我们建议对果蝇的创伤和伤口愈合进行表征，测试候选基因座在创伤和伤口愈合过程中的作用，并进行正向遗传筛选，以恢复无法正常愈合的基因座。这些研究将直接解决上皮伤口愈合的那些方面，这些方面在将昆虫和哺乳动物区分开来的5亿到10亿年的进化过程中是保守的。他们共同承诺，将利用果蝇遗传学和分子遗传学的强大工具来解决这一重要的生物学问题。

Trauma that results in loss of tissue or tissue integrity constitutes a wound, and initiates a wound healing or repair process. Key features of that process include achieving immediate tissue homeostasis, repelling microorganisms and ultimately, the restoration of normal tissue physiology. Wounding and wound healing in humans is of considerable biological and social significance. Wounds occur by accident, can be inflicted in anger, or occur during surgery, for beneficial medical reasons. The ultimate goal of the work we propose is to understand the basic biology of epithelial response to wounds with the long range goal of contributing to the design of intervention strategies designed to speed healing or prevent excessive scarring. A number of vertebrate, and especially mammalian, animal model systems have been developed to study wounding and wound healing. As a consequence, the molecular players responsible for proper wound healing have begun to be identified. Recently, knockout and transgenic mouse technologies have been applied to the study of wound healing. Nevertheless, mammalian model systems can be used in wounding studies only after careful ethical consideration, are naturally time consuming and are very expensive. Moreover, forward genetic screens are essentially impractical. Here, we propose to pursue molecular/genetic strategies that are uniquely available in Drosophila to investigate the biology of wounding and wound healing. Recently we used mechanical and laser methods to ablate tissue in Drosophila embryos and found that such ablations are followed by rapid and robust healing. Moreover, we found that healing was completely inhibited in embryos homozygous for defects in the structural gene for myosin heavy chain. We propose to characterize wounding and wound healing in Drosophila, test the role of candidate loci in the process of wounding and wound healing, and perform forward genetic screens to recover loci that fail to heal properly. These studies will address directly those aspects of epithelial wound healing that are conserved over the 0.5 to 1 billion years of evolution that separate insects from mammals. Together, they promise to bring the powerful tools of Drosophila genetics and molecular genetics to bear on this important biological problem.