The role of Orc6 in DNA replication and cytokinesis

Orc6 在 DNA 复制和胞质分裂中的作用

• 批准号: 9381474
• 负责人: IGOR N CHESNOKOV
• 金额: $ 31.19万
• 依托单位: UNIVERSITY OF ALABAMA AT BIRMINGHAM
• 依托单位国家: 美国
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-09-01 至 2021-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9381474
• 关键词: Affect; Basal Cell Nevus Syndrome; Behavior; Binding; Biochemical; Biological Models; Cell Cycle; Cell Cycle Progression; Cells; Cellular biology; Collaborations; Complex; Cytokinesis; Cytoskeleton; DNA; DNA Binding; DNA biosynthesis; DNA replication origin; Data; Defect; Development; Dimerization; Disease; Drosophila genus; Dwarfism; Electron Microscopy; Eukaryota; Event; Evolution; Filament; Genes; Goals; Growth; Guanosine Triphosphate Phosphohydrolases; Human; In Vitro; Lead; Learning; Length; Licensing; Link; MCM2 gene; Malignant Neoplasms; Mammals; Modeling; Molecular; Molecular Genetics; Mutagenesis; Mutation; N-terminal; Nature; Normal Cell; Organism; Pathogenesis; Peptide Initiation Factors; Polymers; Positioning Attribute; Pre-Replication Complex; Process; Protein Complex Subunit; Proteins; Recruitment Activity; Regulation; Replication Initiation; Replication Origin; Research; Role; Site; Structure; Transcription Factor TFIIB; Translating; cell growth; design; dimer; experimental study; fly; genetic approach; helicase; in vivo; insight; microtia; origin recognition complex; polymerization; protein function; skeletal abnormality

Abstract. The Origin Recognition Complex (ORC), heteromeric six-subunit protein complex, is essential for DNA replication. ORC's functions also extend beyond DNA replication. We found that the smallest of ORC subunit, Orc6 protein, is important for DNA binding and replication and has a structural homology with transcription factor TFIIB suggesting that it may target the formation of pre-replicative complex to the origins of DNA replication. Furthermore, we identified conserved motif within the C- terminus of Orc6 which is responsible for its interaction with the core ORC complex. Mutations in this motif affect the integrity of six-subunit ORC contributing to the pathogenesis of Meier-Gorlin syndrome (MGS) in humans. Orc6 also has a function in cytokinesis. It binds directly to septin complex via its Pnut subunit, stimulates the intrinsic GTPase activity of the Drosophila septin complex and greatly facilitates septin filament formation. The overall goal of our proposal is to characterize the mechanism of Orc6 functions in DNA replication and cytokinesis using Drosophila as a model system. Our experiments are designed to answer important questions about the structure of Orc6, its functions in replication and its role in septin polymerization. Drosophila model systems will be used to analyze the effects of naturally occurring and structure-guided targeted mutations of human Orc6 in diverse protein functions. Because ORC is conserved in evolution, what we learn about its functions in Drosophila will be valuable to our understanding of ORC's functions in other eukaryotes. A better understanding of how ORC functions in Drosophila will provide insights into ORC's behavior in mammals and provide clues as to how its misregulation leads to cancer.

抽象的。 起源识别络合物（ORC），异源六亚基蛋白 复杂，对于DNA复制至关重要。兽人的功能也超出了DNA 复制。我们发现，最小的ORC亚基ORC6蛋白对于 DNA结合和复制，具有带有转录因子的结构同源性 tfiib提出它可能靶向复制前复合物的形成 DNA复制的起源。此外，我们确定了C-内的保守基序 ORC6的末端，其与核心ORC复合物相互作用负责。 该基序中的突变影响六亚基兽人的完整性 人类中Meier-Gorlin综合征（MGS）的发病机理。 ORC6在 细胞因子。它通过其Pnut亚基直接与Septin复合物结合，刺激 果蝇Septin复合物的固有GTPase活性，并极大地促进了Septin 细丝形成。我们建议的总体目标是表征机制 使用果蝇作为模型，在DNA复制和细胞因子中的ORC6功能 系统。我们的实验旨在回答有关 ORC6的结构，其在复制中的功能及其在Septin聚合中的作用。 果蝇模型系统将用于分析自然发生的效果 以及在多种蛋白质功能中人ORC6的结构引导的靶向突变。 因为兽人在进化中是保守的，所以我们对其功能的了解 果蝇将对我们对其他人的功能的理解很有价值 真核生物。更好地理解果蝇中的ORC的功能将提供 深入了解兽人在哺乳动物中的行为，并提供有关其如何的线索 正直导致癌症。