Is CEP290 a vesicle tether at the ciliary base?

为了发挥作用，细胞需要感知环境，操纵周围环境并移动。例如，精子细胞用鞭子一样的尾巴游泳;气道细胞将粘液扫入喉咙，保持肺部清洁;视网膜中的视杆细胞和视锥细胞收集光线，让你看得见;肾脏中的细胞感知尿液的流动。这些不同的功能都是由各种类型的纤毛执行的，纤毛是细胞表面上的手指状细胞器。纤毛存在于许多不同的生物体中，从单细胞藻类到苍蝇和人类。这表明它们在很久以前就进化了，并且非常有用，以至于它们在进化过程中被保留下来并重新用于多种不同的生物功能。这项提议的重点是一种名为CEP 290的蛋白质，它是纤毛中最大的蛋白质之一。CEP 290对于纤毛的正确形成和功能至关重要。当这种蛋白质有缺陷或从细胞中完全缺失时，纤毛不能正确形成，当它们这样做时，它们具有错误的组成，这会损害它们的功能。然而，我们不知道这种蛋白质实际上是什么。我们对它的结构，它如何与其他细胞成分相互作用，以及它的组织如何使它发挥作用知之甚少。细胞充满了被称为囊泡的微小的膜结合的“气泡”，它们将细胞成分从细胞的一部分运输到另一部分。细胞使用囊泡产生纤毛，一旦形成，就用它们正常工作所需的成分“喂养”它们。基于与细胞中其他蛋白的相似性，我们认为CEP 290是一个“囊泡系链”，其作用是捕获含有纤毛成分的囊泡，并引导它们到达纤毛基部的目的地。在本提案中，我们将通过研究CEP 290的分子结构，研究其在体外和细胞内与囊泡的结合，以及这种功能如何依赖于其与膜和其他纤毛蛋白的相互作用来研究这一假设。这将为纤毛如何形成和功能的分子细节提供重要的新见解。CEP 290的基因突变会导致非常广泛的遗传性疾病。这告诉我们，CEP 290在纤毛中起着非常重要的作用，因此我们需要知道它的作用以及它是如何起作用的，以了解纤毛如何工作。由于纤毛和CEP 290存在于从藻类到人类的各种生物体中，这将对生物学产生广泛的影响。值得庆幸的是，由CEP 290突变引起的人类疾病通常很罕见，因为父母双方必须携带致病突变才能产生患有CEP 290相关疾病的孩子（即这些疾病是隐性的）。然而，这些疾病的发病率在近亲社区中要高得多，这些社区往往经历医疗保健不平等，并且不能从研究中充分受益。因此，了解CEP 290突变如何导致疾病将有助于改善遗传咨询和开发基因疗法来预防和治疗这些疾病，这是一个重要的临床和社会未满足的需求。

In order to function, cells need to sense their environment, manipulate their surroundings and move. For example, sperm cells swim using a whip-like tail; the cells lining your airways sweep mucus up into your throat, keeping your lungs clear; rod and cone cells in your retina collect light, allowing you to see; and the cells in your kidneys sense the flow of urine. These diverse functions are all performed by various types of cilia, which are finger-like organelles on the surface of cells. Cilia are found in many different organisms, from single-celled algae, to flies and humans. This shows that they evolved a very long time ago and are so useful that they have been retained and repurposed for a multitude of different biological functions during evolution.This proposal focuses on a protein called CEP290, which is one of the largest proteins in cilia. CEP290 is essential for the correct formation and function of cilia. When this protein is defective or missing from cells entirely cilia do not form correctly, and when they do, they have the wrong composition, which compromises their function. However, we don't understand what this protein actually does. We know very little about its structure, how it interacts with other cellular components, and how its organisation allows it to function. Cells are full of tiny membrane-bound "bubbles", called vesicles, that transport cellular components from one part of the cell to the other. The cell uses vesicles to generate cilia and, once formed, "feed" them with the components they need to function properly. Based on similarities with other proteins in the cell, we think that CEP290 is a "vesicle tether", whose role is to capture vesicles that contain cilium components and guide them to their destination at the cilium base. In this proposal we will investigate this hypothesis by investigating the molecular structure of CEP290, studying its binding to vesicles in vitro and inside cells, and how this function relies on its interactions with membranes and other cilium proteins. This will provide essential new insights into the molecular details of how cilia form and function.Genetic mutations in CEP290 cause a very broad range of inherited disorders. This tells us that CEP290 does something very important in cilia, and hence that we need to know what it does and how it does it to understand how cilia work. As cilia and CEP290 are found in such a wide range of organisms, from algae to humans, this will have wide-ranging implications for biology. Thankfully, human diseases caused by CEP290 mutations are rare in general, since both parents must carry a disease-causing mutation to produce children with a CEP290-related disorder (i.e. these disorders are recessive). However, the incidence of these disorders is much higher in consanguineous communities, which are often experience healthcare inequality and do not benefit fully from research. Thus, understanding how CEP290 mutations cause disease will help improve genetic counselling and develop gene therapies to prevent and treat these conditions, which is an important clinical and societal unmet need.