The role of Orc6 in DNA replication and cytokinesis.

Orc6 在 DNA 复制和胞质分裂中的作用。

基本信息

批准号：
10458042
负责人：
IGOR N CHESNOKOV
金额：
$ 33.41万
依托单位：
UNIVERSITY OF ALABAMA AT BIRMINGHAM
依托单位国家：
美国
项目类别：
财政年份：
2017
资助国家：
美国
起止时间：
2017-09-01 至 2025-07-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10458042
关键词：
Address Amino Acids Basal Cell Nevus Syndrome Binding Biochemical Biological Models Cell Cycle Cell Cycle Progression Cells Cellular biology Complex Cytokinesis Cytoskeleton DNA DNA Binding DNA biosynthesis DNA replication origin Data Defect Development Dimerization Disease Drosophila genus Dwarfism Electron Microscopy Eukaryota Filament Genes Goals Growth Guanosine Triphosphate Phosphohydrolases Human Impairment In Vitro Lead Length Licensing Link MCM2 gene Modeling Molecular Molecular Genetics Mutagenesis Mutation Nature Normal Cell Organism Peptide Initiation Factors Phenotype Polymers Positioning Attribute Pre-Replication Complex Process Protein Complex Subunit Proteins Regulation Replication Origin Research Role Site Structure Translating base cell growth dimer experimental study fly genetic approach helicase in vitro testing in vivo insight mutant origin recognition complex polymerization protein function recruit

项目摘要

Abstract. The Origin Recognition Complex (ORC), a heteromeric six-subunit protein complex, is essential for DNA replication. ORC's functions also extend beyond DNA replication. The smallest of ORC subunits, Orc6 protein, is important for DNA replication in all eukaryotes. We have shown that in Drosophila Orc6 has an additional role in cytokinesis through interaction with the septin complex, a highly conserved polymerizing protein assembly that is critical for cytokinesis in many species and is recognized as important component of the cytoskeleton. In preliminary studies we solved the structure of human Orc6 and identified its structural features that contribute directly to the functions of the protein in replication and cytokinesis. We characterized the mutations in different domains of Orc6 leading to Meier-Gorlin syndrome (MGS) in humans, an autosomal recessive disorder characterized by primordial dwarfism and developmental abnormalities. We showed that despite different underlying molecular mechanisms these mutations resulted in similar phenotypes, defects in pre-RC formation and impaired DNA replication. Thus, the diverse molecular functions of Orc6 can be experimentally dissected to obtain a complete understanding of its discrete roles in the cell. The overall goal of this proposal is to define the distinct mechanisms of Orc6 function in DNA replication and in cytokinesis using Drosophila as a model system. We established a humanized Orc6-based Drosophila model system which will be used to analyze the effects of naturally occurring and structure-guided targeted mutations of human Orc6 in protein functions. Regulatory insights into replicative and non-replicative functions of ORC in metazoans are limited, despite decades of research. Our completion of this project will help to fill this gap in our understanding of diverse ORC's functions in metazoans and provide clues as to how a specific mutation or mis-regulation would lead to growth and developmental defects.

抽象的。起源识别复合物 (ORC)，一种异聚六亚基蛋白复杂，对于 DNA 复制至关重要。 ORC的功能也超越了DNA 复制。最小的 ORC 亚基 Orc6 蛋白对 DNA 非常重要在所有真核生物中复制。我们已经证明在果蝇中 Orc6 有一个额外的通过与septin复合物相互作用在胞质分裂中发挥作用，septin复合物是高度保守的聚合蛋白组装对许多物种的胞质分裂至关重要被认为是细胞骨架的重要组成部分。在初步研究中我们解析了人类 Orc6 的结构并确定了其结构特征，这些特征有助于直接影响蛋白质在复制和胞质分裂中的功能。我们表征 Orc6 不同结构域的突变导致 Meier-Gorlin 综合征 (MGS) 人类，一种以原始侏儒症为特征的常染色体隐性遗传疾病发育异常。我们表明，尽管潜在的分子不同这些突变导致相似的表型、pre-RC 缺陷的机制形成和DNA复制受损。因此，Orc6 的多种分子功能可以通过实验剖析以获得对其离散的完整理解在细胞中的作用。该提案的总体目标是定义不同的机制以果蝇为模型研究 Orc6 在 DNA 复制和胞质分裂中的功能系统。我们建立了基于Orc6的人性化果蝇模型系统，该系统将用于分析自然发生的和结构引导的目标的影响人类 Orc6 蛋白质功能突变。对复制和复制的监管见解尽管数十年来，ORC在后生动物中的非复制功能仍然有限。研究。我们完成这个项目将有助于填补我们理解上的这一空白不同的 ORC 在后生动物中的功能，并提供关于特定突变如何发生的线索或调节不当会导致生长和发育缺陷。