Centrosomin and centrosomes in cell division

细胞分裂中的中心体蛋白和中心体

• 批准号: 7731843
• 负责人: TIMOTHY L MEGRAW
• 金额: $ 30.56万
• 依托单位: FLORIDA STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-08-01 至 2013-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7731843
• 关键词: Actins; Adult; Affect; Aneuploidy; Animals; Auras; Binding; Binding Sites; Biochemistry; Biological Models; Body Size; Brain; Categories; Cell Cycle; Cell division; Cells; Cellular biology; Centrioles; Centrosome; Chest; Chromosomal Instability; Cilia; DNA damage checkpoint; Defect; Development; Developmental Process; Disease; Drosophila genus; Embryo; Family member; Foundations; Funding; Genes; Goals; Homologous Gene; Human; Hydrocephalus; Image; In Vitro; Kinetics; Label; Licensing; Life; Link; Malignant Neoplasms; Mammals; Maps; Measures; Messenger RNA; Microcephaly; Microtubule-Organizing Center; Microtubules; Mitosis; Mitotic; Mitotic spindle; Modeling; Molecular; Molecular Genetics; Mus; Mutant Strains Mice; Mutation; Obesity; Organ; Organelles; Orthologous Gene; Pathology; Pathway interactions; Phase; Phosphotransferases; Physiological Processes; Plant Roots; Play; Polycystic Kidney Diseases; Polymerase; Predisposition; Probability; Process; Protein Family; Proteins; Recruitment Activity; Regulation; Research; Role; Signal Transduction; Site; Speed; Spermatocytes; Structure; Syndrome; System; Testing; Vertebrate Biology; Work; Workplace; aurora-A kinase; base; cancer cell; cohesion; deafness; fly; gene function; human disease; in vivo; kinetosome; mouse model; mutant; nerve stem cell; novel; pericentrin; polymerization; prevent; protein function; public health relevance; reconstitution; tool; tumor progression

DESCRIPTION (provided by applicant): Centrioles and centrosomes are conserved organelles in animals that are essential for cell signaling, cell division, and for specialized roles in differentiated cells, impacting organ function in whole animals. Mutations in proteins that function in centriole/basal body assembly or function, or which impact the cilia that grow from basal bodies, comprise the etiological basis for an expanding category of developmental and disease genes. Mutations in genes for other centrosomal proteins like CDK5RAP2, Pericentrin, sas4 and Aspm, are the root cause of related syndromes that affect brain and/or body size, yet an understanding of the connection between function at the centrosome and the causes of disease are unclear. To understand the disease or developmental process, we must first understand the functions of the proteins affected. Here we focus on the Centrosomin family of proteins. A key breakthrough came with mutation studies of Drosophila Centrosomin (CNN), showing that it is required in an early process of mitotic centrosome assembly. Centrosomes are the major microtubule-organizing centers (MTOCs) in animal cells and are required for efficient assembly of microtubules into the bipolar spindle apparatus at mitosis. The molecular functions of centrosome and centriole proteins are largely uncharacterized; indeed, the centrosome "parts list" is still being compiled. We employ Drosophila as a model system to investigate the molecular function of Centrosomin (Cnn) and the proteins and processes it impacts. With this model we combine classical and molecular genetic approaches with cell biology and biochemistry, capitalizing on the efficiency and rich tool chest that this model affords. The estimated 70% of human disease genes with homologs in Drosophila validate its use as a model for vertebrate biology. Yet, by employing a mouse mutant for CDK5RAP2, a mouse CNN family member, we bridge these systems and achieve a closer understanding of the pathology that underlies mutations in CDK5RAP2, which cause microcephaly in humans. CNN contains two conserved modules. One domain, near the N-terminus, regulates microtubule assembly at centrosomes, while the second domain at the C-terminus regulates actin organization into cleavage furrows. The first domain functions to recruit a microtubule assembly factor to centrosomes, while the second domain binds directly to Centrocortin (Cen), a novel factor required for cleavage furrow assembly. In mice, CDK5RAP2 mutant cells lose centriole engagement and cohesion, inducing centriole amplification. At mitosis, these excess centrosomes induce multipolar spindle assembly, implicating a role for CDK5RAP2 in centrosome clustering at mitosis. The multiple centrioles also template multiple primary cilia in CDK5RAP2 mutant cells. These findings pave a path toward a deeper understanding of the key processes that centrosomes regulate and that govern the regulation of centrosome replication. Our specific aims are to: 1. Determine the mechanisms of MTOC regulation by CNN, 2. Define the role of Centrocortin and its cooperation with CNN in cleavage furrow assembly, and 3. Define the functions of CDK5RAP2 in the mouse. PUBLIC HEALTH RELEVANCE: Mutations in genes that function at centrioles and centrosomes cause a host of human disorders due to their importance in so many developmental and physiological processes. These ailments include polycystic kidney disease, deafness, hydrocephaly, obesity, microcephaly, and more. The goal of this proposal is to gain molecular and mechanistic understanding of centrioles and centrosomes, structures found in nearly every cell, in flies and mice and discern the pathology of autosomal recessive primary microcephaly (MCPH).

描述（由申请人提供）：中心粒和中心体是动物中保守的细胞器，对于细胞信号传导，细胞分裂以及在分化细胞中的专门作用，影响整个动物的器官功能。在中心/基体组装或功能中起作用的蛋白质突变，或影响纤毛从基底体中生长的蛋白质，包括扩展的发育和疾病基因类别的病因基础。其他中心蛋白（如CDK5RAP2，包中环蛋白，SAS4和ASPM）的基因突变是影响大脑和体大小的相关综合症的根本原因，但尚不清楚对中心体和疾病原因之间的联系的理解。要了解疾病或发育过程，我们必须首先了解受影响的蛋白质的功能。在这里，我们专注于中心蛋白家族。果蝇中心素（CNN）的突变研究表明，在有丝分裂中心体组装的早期过程中，这是必需的。中心体是动物细胞中主要的微管组织中心（MTOC），是在有丝分裂时有效地组装微管进入双极纺锤体所必需的。中心体和中心蛋白的分子功能在很大程度上没有特征。确实，中心体的“零件清单”仍在编译中。我们利用果蝇作为模型系统来研究中心素（CNN）的分子功能以及蛋白质和过程的影响。通过这种模型，我们将经典和分子遗传学方法与细胞生物学和生物化学相结合，利用该模型提供的效率和丰富的工具箱。果蝇中估计具有同源物的人类疾病基因的70％验证了其用作脊椎动物生物学的模型。然而，通过使用小鼠CNN家族成员CDK5RAP2的小鼠突变体，我们桥接了这些系统，并对CDK5RAP2中突变的病理进行了更深入的了解，CDK5RAP2引起了人类的小头畸形。 CNN包含两个保守的模块。一个域附近N端，调节中心体的微管组件，而C末端的第二个域则将肌动蛋白组织调节为裂解沟。第一个结构域的功能将微管组装因子募集到中心体，而第二个结构域直接与中心皮质素（CEN）结合，这是裂解沟组装所需的新因子。在小鼠中，CDK5RAP2突变细胞失去了中心的互动和凝聚力，从而诱导了中心扩增。在有丝分裂时，这些过量的中心体诱导多极纺锤体组件，这暗示了CDK5RAP2在有丝分裂中的中心体聚类中的作用。多个中心元还模板在CDK5RAP2突变细胞中的多个原代纤毛。这些发现铺平了对集中调节的关键过程和控制中心体复制的调节的途径。我们的具体目的是：1。确定CNN的MTOC调控机制，2。定义中心皮质素的作用及其与CNN在裂解沟组装中的合作，并定义CDK5RAP2在小鼠中的功能。公共卫生相关性：在中心和中心体中起作用的基因突变引起了许多人类疾病，因为它们在许多发育和生理过程中的重要性。这些疾病包括多囊性肾脏疾病，耳聋，脑畸形，肥胖，小头畸形等。该建议的目的是获得对中心和中心体的分子和机械理解，几乎每个细胞中的结构，蝇和小鼠，并辨认出常染色体隐性原发性小头畸形（MCPH）的病理。