Regulation of matrix metalloproteinase activity during tissue remodelling

组织重塑过程中基质金属蛋白酶活性的调节

• 批准号: RGPIN-2018-04559
• 负责人: Crawford, Bryan
• 金额: $ 2.33万
• 依托单位: University of New Brunswick
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2020
• 资助国家: 加拿大
• 起止时间: 2020-01-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=713099
• 关键词: Regulation; matrix; metalloproteinase; activity; during

Tissues are comprised of cells and a complex matrix of proteins cells secrete and adhere to. This extracellular matrix (ECM) is constantly remodeled, most obviously during the dramatic growth and cellular rearrangements of embryonic development, but also during wound healing and as part of the process of ageing. Cells remodel the ECM using a complex family of enzymes called matrix metalloproteinases (MMPs). Because MMPs digest all of the ECM proteins, their activity must be carefully regulated or tissues would disintegrate. Not surprisingly, defects in MMP regulation are causes and/or effects of a variety of diseases, including arthritis, heart disease and cancer. But surprisingly little is known about the regulation of MMP activity in living tissues; most of what we have learned comes from experiments done on isolated cells in petri dishes, and biochemical experiments with purified proteins. Zebrafish are an excellent model organism for biomedical research and we have identified all of the MMPs and their known regulators in the zebrafish genome. Because the zebrafish embryo is transparent, and develops externally and rapidly, we can observe the effects of manipulating MMP activity relatively easily. Furthermore, we have developed techniques that take advantage of the transparency of the fish embryo to visualize MMP activity, and to detect the biochemical events that regulate these ECM-remodeling proteases in the intact embryo. We have developed a novel transgenic line of zebrafish that expresses an engineered protein, which reports on the activation of one of these MMPs. Using these embryos we will generate the first ever map' of when and where this MMP becomes activated during development. Furthermore, using these embryos we can find out if the biochemical mechanisms that are thought to regulate this MMP are actually occurring in the living animal. Invasive cells use MMPs to degrade the boundaries between tissues, allowing them to migrate through the body. This is essential for normal embryonic development, wound healing, and the immune response, but it is also how tumour cells metastasize. We would therefore like to better understand how MMPs are regulated at the interface between normally and pathologically invasive cell types. We can transplant human tumour cells into zebrafish embryos and observe them as they proliferate and spread through the embryo. Using our transgenic line and other tools, we can test hypotheses about how invasive cells use their own MMPs and/or the MMPs present in the surrounding tissues to degrade the ECM, allowing them to invade and move through the embryo. This will not only help us understand how embryos build themselves and how tissues maintain and regenerate their structure after injury, but also how MMPs become activated under pathological conditions that cause damage to tissues, and allow tumors to spread throughout the body.

组织由细胞和细胞分泌和粘附的蛋白质的复杂基质组成。这种细胞外基质（ECM）不断重塑，最明显的是在胚胎发育的急剧生长和细胞重排期间，但也在伤口愈合期间和作为衰老过程的一部分。细胞使用称为基质金属蛋白酶（MMPs）的复杂酶家族重塑ECM。由于基质金属蛋白酶消化所有的ECM蛋白，它们的活性必须仔细调节，否则组织会解体。MMP调节的缺陷是多种疾病的原因和/或影响，包括关节炎、心脏病和癌症，这并不奇怪。但令人惊讶的是，我们对活组织中MMP活性的调节知之甚少;我们所了解的大部分来自培养皿中分离细胞的实验，以及纯化蛋白质的生化实验。 斑马鱼是生物医学研究的一个很好的模式生物，我们已经确定了斑马鱼基因组中所有的MMPs及其已知的调节因子。由于斑马鱼胚胎是透明的，并且外部发育迅速，我们可以相对容易地观察到操纵MMP活性的影响。此外，我们已经开发了利用鱼胚胎的透明度来可视化MMP活性的技术，并检测在完整胚胎中调节这些ECM重塑蛋白酶的生化事件。我们已经开发了一种新的转基因斑马鱼系，表达一种工程蛋白，报告这些MMP之一的激活。利用这些胚胎，我们将生成有史以来第一张MMP在发育过程中何时何地被激活的地图。此外，使用这些胚胎，我们可以发现被认为调节这种MMP的生化机制是否真的发生在活体动物中。 侵袭性细胞使用MMPs来降解组织之间的边界，使它们能够在体内迁移。这对正常的胚胎发育、伤口愈合和免疫反应至关重要，但它也是肿瘤细胞转移的方式。因此，我们希望更好地了解MMPs是如何在正常和病理侵袭性细胞类型之间的界面进行调节的。我们可以将人类肿瘤细胞移植到斑马鱼胚胎中，并观察它们在胚胎中的增殖和扩散。使用我们的转基因系和其他工具，我们可以测试关于侵入性细胞如何使用它们自己的MMPs和/或周围组织中存在的MMPs来降解ECM的假设，使它们能够侵入并穿过胚胎。这不仅有助于我们了解胚胎如何自我构建以及组织如何在损伤后维持和再生其结构，还有助于我们了解MMPs如何在导致组织损伤的病理条件下被激活，并使肿瘤扩散到全身。