The Golgi apparatus as an initiator of ciliogenesis

高尔基体作为纤毛发生的启动者

• 批准号: MR/K018019/1
• 负责人: David Stephens
• 金额: $ 46.95万
• 依托单位: University of Bristol
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2013
• 资助国家: 英国
• 起止时间: 2013 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=MR%2FK018019%2F1
• 关键词: Golgi; apparatus; initiator; ciliogenesis

The ability of cells to sense and respond to the environment is critical at all stages of life. This is perhaps most important during development as cells differentiate into specific tissue types. Most cells in the human body extend a primary cilium that acts as an antenna to sense and respond to the extracellular environment. Primary cilia are required for proper developmental signalling and any defect in a cells ability to form a cilium causes serious developmental defects. These diseases, collectively known as the ciliopathies, include specific syndromes such as Meckel-Gruber and Bardet-Biedel Syndrome as well as polycystic kidney disease and short rib polydactyly. We are beginning to understand the causes of these diseases by defining the causative mutations in single genes. A key to this is to ensure that we fully understand the way in which these primary cilia are built and maintained. Cilia are extensions of a specialised set of microtubule filaments called the axoneme that are surrounded by a high specialised membrane. This process requires a close cooperation of two key cellular elements - the cytoskeleton and the membranes. We have identified a source of the initial membrane that drives the formation of the cilium. For many years we have worked on transport of membranes and proteins through the cell and recently this has led us serendipitously to discover that one of the key proteins that we have studies for many years, giantin, is in fact required for cells to make cilia. We have identified a mechanism by which this occurs which links giantin, a membrane protein of the Golgi apparatus, to dynein-2, one of two of the main motor proteins that drives transport within the cilium. The Golgi is the central organelle of the secretory pathway in all mammalian cells and it is responsible for the modification and sorting of proteins destined for all major cellular organelles. As such it also lies directly adjacent to the centrosome from which the microtubule axoneme extends. Dynein-2 is known to be required for cilium function and mutations in this complex cause a variety of cilia-related disorders in vitro and in patients. We propose that giantin acts through dynein-2 to control the earliest stages of assembly of cilia. Now we wish to use our extensive experience of membrane and microtubule dynamics, in particular live cell imaging, to define this role in detail. We have established collaborations with key labs in the UK, USA, and France that mean we are well placed to drive this work forwards. Our experiments will study the delivery of key components to the newly emerging cilium as well as the organization of membranes around the microtubule axoneme. We expect these experiments to define the role of the Golgi in forming the cilium and lead to new avenues of research in terms of pathways that one might approach to modulate ciliary function as well as identifying candidate genes that might underlie those ciliopathies for which a genetic defect is not yet defined.

细胞感知和响应环境的能力在生命的各个阶段都至关重要。这在发育过程中可能是最重要的，因为细胞分化成特定的组织类型。人体中的大多数细胞都延伸出初级纤毛，其充当天线来感知和响应细胞外环境。初级纤毛是正常发育信号所必需的，细胞形成纤毛能力的任何缺陷都会导致严重的发育缺陷。这些疾病统称为纤毛病，包括特定的综合征，如Meckel-Gruber和Bardet-Biedel综合征以及多囊肾病和短肋多指（趾）。我们开始通过定义单个基因中的致病突变来了解这些疾病的原因。其中一个关键是要确保我们完全理解这些初级纤毛的建立和维持方式。纤毛是一组被称为轴丝的特殊微管细丝的延伸，轴丝被高度特化的膜包围。这一过程需要两个关键的细胞元件-细胞骨架和细胞膜的密切合作。我们已经确定了驱动纤毛形成的初始膜的来源。多年来，我们一直致力于研究细胞膜和蛋白质在细胞中的转运，最近，这使我们偶然发现，我们研究多年的关键蛋白之一Giantin实际上是细胞制造纤毛所必需的。我们已经确定了一种机制，通过这种机制发生连接giantin，高尔基体的膜蛋白，动力蛋白2，驱动纤毛内运输的两个主要马达蛋白之一。高尔基体是所有哺乳动物细胞分泌途径的中心细胞器，负责所有主要细胞器的蛋白质的修饰和分选。因此，它也直接位于微管轴丝延伸的中心体附近。动力蛋白-2是纤毛功能所必需的，该复合物的突变在体外和患者中引起多种纤毛相关疾病。我们建议，giantin通过动力蛋白-2控制纤毛组装的最早阶段。现在，我们希望利用我们在膜和微管动力学方面的丰富经验，特别是活细胞成像，来详细定义这种作用。我们已经与英国、美国和法国的主要实验室建立了合作关系，这意味着我们有能力推动这项工作向前发展。我们的实验将研究关键成分的新出现的纤毛以及微管轴丝周围的膜组织的交付。我们希望这些实验来定义高尔基体在形成纤毛中的作用，并导致新的研究途径，人们可能会接近调节纤毛功能，以及确定候选基因，可能是那些纤毛病的遗传缺陷尚未定义。

项目成果

TFG Promotes Organization of Transitional ER and Efficient Collagen Secretion

TFG 促进过渡性 ER 组织和高效胶原蛋白分泌

• DOI: 10.15488/500
• 发表时间: 2016
• 作者: McCaughey J

Cep126 is required for pericentriolar satellite localisation to the centrosome and for primary cilium formation.

• DOI: 10.1111/boc.201300087
• 发表时间: 2014-08
• 期刊: Biology of the cell
• 影响因子: 2.7
• 作者: Bonavita R;Walas D;Brown AK;Luini A;Stephens DJ;Colanzi A
• 通讯作者: Colanzi A

Subunit composition of the human cytoplasmic dynein-2 complex.

• DOI: 10.1242/jcs.159038
• 发表时间: 2014-11-01
• 期刊: Journal of cell science
• 影响因子: 4
• 作者: Asante D;Stevenson NL;Stephens DJ
• 通讯作者: Stephens DJ

TFG Promotes Organization of Transitional ER and Efficient Collagen Secretion.

TFG促进了过渡性和有效胶原蛋白分泌的组织。

• DOI: 10.1016/j.celrep.2016.04.062
• 发表时间: 2016-05-24
• 期刊: Cell reports
• 影响因子: 8.8
• 作者: McCaughey J;Miller VJ;Stevenson NL;Brown AK;Budnik A;Heesom KJ;Alibhai D;Stephens DJ
• 通讯作者: Stephens DJ

The Golgi matrix protein giantin is required for normal cilia function in zebrafish.

斑马鱼中正常的纤毛功能需要Golgi基质蛋白巨蛋白。

• DOI: 10.1242/bio.025502
• 发表时间: 2017-08-15
• 期刊: Biology open
• 影响因子: 2.4
• 作者: Bergen DJM;Stevenson NL;Skinner REH;Stephens DJ;Hammond CL
• 通讯作者: Hammond CL