DNA replication a checkpoint in regulating development in Myxococcus xanthus

Mitchell SingerDNA复制在调节Myxococcus xanthus发育中的一个检查点建议编号：1354562项目摘要：了解单个细胞如何与环境相互作用以及环境如何塑造和调节细胞生长和分化对于所有生命都是至关重要的，从单细胞生物（如细菌）到复杂的多细胞生物（如人类）。 这个项目解决了这个基本问题，关于粘球菌xanthus，一个简单的发育细菌系统。 M.黄色素细胞在称为生物膜的社会群体中生长，其中生长的细胞汇集它们分泌的消化酶以分解环境中的复杂大分子。 当营养物质变得有限时，M. xanthus的反应是激活一个发育程序，导致一个称为子实体的多细胞结构的构建。 在这种结构中，细胞亚群形成耐环境的粘孢子。 该项目特别侧重于确定促进粘孢子形成的分子机制，而其他细胞要么进行自我毁灭，要么形成一种称为外周杆细胞的不同类型的细胞。这个项目测试的假设，一个细胞的命运（孢子，杆，或死亡）是由多远沿着它是在细胞分裂周期时，它遇到的信号，开始子实体形成。实验的目的是使用分子，生物化学和生理学的方法来验证这一假设。 该项目预计将促进我们对细菌发育，分子信号和饥饿生理学的理解。 M. Xanthus是重要细菌家族的代表，其抗生素、抗肿瘤和抗真菌化合物的产生与多细胞发育有关。该项目将继续作为研究生，本科生和高中生的实验室培训，他们将继续长期从事科学事业。最后，该项目为当地一所一级小学提供社区外展服务。

Mitchell SingerDNA replication a checkpoint in regulating development in Myxococcus xanthusProposal number: 1354562Project Abstract:Understanding how individual cells interact with their environment and how that environment shapes and regulates cell growth and differentiation is fundamental to all life, from single celled organisms such as bacteria, to complex multicellular organisms such as humans. This project addresses this basic question, with respect to Myxococcus xanthus, a simple developmental bacterial system. M. xanthus cells grow in social groups called biofilms, in which the growing cells pool their secreted digestive enzymes to breakdown complex large molecules from the environment. When nutrients become limiting, M. xanthus responds by activating a developmental program that results in the construction of a multicellular structure called a fruiting body. Within this structure, a subpopulation of cells forms environmentally resistant myxospores. This project specifically focuses on determining the molecular mechanisms that promote the formation of myxospores, while other cells either undergo self-destruction or form a different type of cell called a peripheral rod cell. This project tests the hypothesis that the fate of a cell (spore, rod, or death) is determined by how far along it is in the cell division cycle when it encounters the signal to begin fruiting body formation. Experiments are designed to test this hypothesis using molecular, biochemical and physiological approaches. The project is expected to advance our understanding of bacterial development, molecular signaling, and starvation physiology. M. xanthus is a representative of a family of pharmacologically important bacteria, whose production of antibiotic, anti-tumor and anti-fungal compounds is tied to multicellular development. This project will continue to serve as laboratory training to graduate, undergraduate and high school students, who will continue with long-term careers in science. Finally this project provides community outreach to a title 1 local elementary school.