Cell Differentiation and the Cell Cycle

细胞分化和细胞周期

• 批准号: 0744566
• 负责人: John Larkin
• 金额: $ 40.18万
• 依托单位: Louisiana State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-02-15 至 2013-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0744566&HistoricalAwards=false
• 关键词: Cell; Differentiation; Cycle

During the development of multicellular organisms, cell differentiation is tightly coordinated with cell division. In animals, loss of control of cell division leads to cancer. In some cell types, a modified cell cycle occurs during differentiation in which the DNA is replicated without concomitant cell division, resulting in an increase in nuclear DNA content. This process is called endoreplication; in plants, important examples of endoreplicated cell types include cereal endosperm, cotton fibers, and nitrogen-fixing symbiotic nodules in legumes. The coordination of this modified cell cycle with cell differentiation remains poorly understood. Previous work using Arabidopsis leaf hairs (trichomes) as a model for cell differentiation demonstrated that the SIAMESE (SIM) gene encodes a cell cycle regulator necessary for the suppression of mitosis during establishment of endoreplication in trichomes. The goal of the proposed work is to test a proposed mechanism for the establishment of endoreplication. The proposed work is expected to shed light on the establishment of the endocycle, and on the integration of the cell cycle with development. The proposed role for SIM focuses on a stage of the cell cycle that is not well-understood in any organism; thus the proposed work may also shed light on the mitotic cycle in both plants and animals. Additionally, the proposed work will play a role in the education of graduate students, undergraduates, and high school students from a wide diversity of backgrounds.

在多细胞生物的发育过程中，细胞分化与细胞分裂是紧密协调的。在动物身上，失去对细胞分裂的控制会导致癌症。在某些细胞类型中，在分化过程中发生了一个修饰的细胞周期，其中DNA被复制而没有伴随细胞分裂，导致细胞核DNA含量增加。这个过程被称为内复制；在植物中，内复制细胞类型的重要例子包括谷物胚乳、棉花纤维和豆科植物的固氮共生根瘤。这种改变的细胞周期与细胞分化的协调仍然知之甚少。先前使用拟南芥叶毛（毛状体）作为细胞分化模型的研究表明，SIAMESE （SIM）基因编码一个细胞周期调节因子，在毛状体建立内复制过程中抑制有丝分裂。提出的工作的目标是测试提出的机制建立内复制。拟议的工作有望阐明内周期的建立，以及细胞周期与发育的整合。SIM的作用主要集中在细胞周期的一个阶段，这个阶段在任何生物体中都没有得到很好的理解；因此，提出的工作也可能阐明植物和动物的有丝分裂周期。此外，所建议的工作将在研究生、本科生和来自不同背景的高中生的教育中发挥作用。