Assessing defects in embryonic development due to loss of protein fucosylation

蛋白质聚焦是一个进化保守过程，发生在所有动物中。蛋白质聚焦化是指在靶蛋白上添加糖（聚焦）分子，以保证其正常功能。我们用小咸淡鱼（Danio rerio）来研究当蛋白质聚焦被破坏时胚胎会发生什么。在这些鱼的蛋白质集中所需的基因发生突变后，它们的胚胎出现了脑出血。这表明，构建稳定、正常运作的血管需要蛋白质聚焦。我们用斑马鱼试着弄清楚这种基因，以及蛋白质的集中化，是如何构建血管的。除了脑出血外，蛋白质集中缺陷的斑马鱼还有许多其他问题。例如，它们的尾巴是弯曲的，它们绕着圈子游泳。这些问题和脑出血都可以用纤毛缺陷来解释。纤毛是位于几乎所有人体细胞上的重要结构，对正常胚胎发育至关重要。例如，纤毛可以使液体在脊柱中流动，已知这些纤毛的缺陷会导致鱼类的尾巴弯曲。斑马鱼的身体外部也有纤毛，可以探测水流的变化，而这些纤毛的缺陷会导致循环游泳的行为。最后，纤毛直指我们的血管，在血管发育和调节血压方面起着重要作用。已知这些纤毛的缺陷会引起脑出血。在我的实验室里，我们可以看到突变斑马鱼缺乏蛋白质聚焦的纤毛，看看是否有任何缺陷。我们观察血管中的纤毛，脊柱中的纤毛，以及身体外部的纤毛，看看是否有缺陷的纤毛导致了脑出血，弯曲的尾巴，以及蛋白质聚焦缺陷斑马鱼的环形游泳行为。这项工作对于帮助我们了解纤毛的功能以及它们的重要性，并帮助我们了解它们对人类的重要性是非常重要的。例如，导致斑马鱼弯曲尾巴的纤毛缺陷可能导致人类脊柱侧弯（脊柱弯曲）。人类耳朵里有帮助我们听声音的纤毛，在结构上与斑马鱼外面帮助它们游泳的纤毛几乎完全相同。由于纤毛的问题，人类患脑血管缺陷的风险也会增加，所以我们的斑马鱼可以作为一个有用的工具来了解导致血管疾病（如中风）的潜在生物学问题。最后，由于所有动物都需要蛋白质聚焦，我们的工作可以跨学科转化，为我们提供其他动物如何利用蛋白质聚焦来维持正常身体功能的线索。

Lay Summary Protein fucosylation is an evolutionary conserved process that occurs in all animals. Protein fucosylation refers to the addition of sugar (fucose) molecules to target proteins in order to ensure their proper function. We use the small brackish fish, (Danio rerio) to study what happens to an embryo when protein fucosylation is disrupted. Upon making a mutation in a gene required for protein fucosylation in these fish, their embryos developed cerebral hemorrhages. This indicates that protein fucosylation is required to build stable, functioning blood vessels. We use the zebrafish to try and figure how the gene, and protein fucosylation in general, is required to build blood vessels. Zebrafish with defects in protein fucosylation have a number of other problems in addition to cerebral hemorrhages. For example, their tails are bent and they swim in circles. These problems, and the cerebral hemorrhages, can all be explained by defective cilia. Cilia are important structures located on almost all of our bodies cells, and are critically important for normal embryo development. Cilia for example, can beat and move fluid through the spinal columns, and defects in these cilia are known to cause bent tails in fish. Zebrafish also have cilia on the outside of their body that detect changes in water currents, and defects in these cilia can cause circular swimming behavior. Finally, cilia point into our blood vessels, and play an important role in vessel development and the regulation of blood pressure. Defects in these cilia are known to cause cerebral hemorrhages. In my lab, we are able to visualize cilia in our mutant zebrafish that lack protein fucosylation, to see if there are any defects. We look at the cilia in blood vessels, in the spinal column, and on the outside of the body to see if defective cilia are responsible for the cerebral hemorrhages, bent tails, and circular swimming behavior in our protein fucosylation deficient zebrafish. This work is important to help us understand how cilia function and why they are important, and help us to learn about how they might be important in humans. For example, defects in cilia that cause bent tails in zebrafish can cause scoliosis (bent spines) in humans. Humans have cilia in our ears that help us hear, and are almost identical in structure to the cilia on the outside of zebrafish that help them swim. Humans can also be at increased risk for cerebral blood vessel defects due to problems with cilia, so our zebrafish serve as a useful tool to understand the underlying biological problems that lead to vascular diseases such as stroke. Lastly, as all animals require protein fucosylation, our work can translate across scientific disciplines to give us clues as to how other animals use protein fucosylation in order to maintain normal body function.