Coordinating Developmental Gene Expression in Myxococcus xanthus

安东尼·G·加尔扎IOS-0950976在黄色粘球菌中协调发育基因表达大多数细菌生活在称为生物膜的有组织的多细胞群落中。生物膜与对人类很重要的各种问题有关：生物膜污染供水、医疗设备和工业机械，生物膜导致许多持续性感染。微生物学的一个基本目标是了解这些有趣和重要的细菌群落是如何发展的。最近，很明显，细菌使用一些保守的设计原则来建立生物膜。也就是说，细胞产生细胞外信号来传递关于细胞密度和细胞位置的信息，这些信息被用来调节发育基因的时间和空间表达。本课题主要研究黄色粘球菌的发育基因调控。在饥饿时，黄曲霉形成一层生物膜，其中包含一层薄薄的细胞和多细胞子实体结构。一系列增强子结合蛋白(EBPs)被用来调节许多发育基因，它被设计成对各种细胞外信号做出反应。这个项目的长期目标是了解这个调控网络如何协调发育中的基因表达，并最终了解它如何促进生物膜的组装。EBP Nla4在级联的前端发挥作用，调节进入开发阶段。该项目的目的是了解Nla4如何帮助细胞度过发育的关键时刻。具体地说，该项目旨在寻找Nla4靶基因，了解Nla4是如何识别靶启动子的，并确定这些靶基因是否对发育重要。类似于EBP级联的调控网络似乎将成为形成生物膜的细菌的共同主题，因为它们还必须处理各种信号信息，以适当地调节它们的发育基因。因此，我们相信这个项目将导致一个与许多细菌系统相关的基因调控模型。

Anthony G. GarzaIOS-0950976Coordinating Developmental Gene Expression in Myxococcus xanthus Most bacteria live in organized multicellular communities called biofilms. Biofilms have been linked to a variety of problems important to humans: biofilms contaminate water supplies, medical equipment, and industrial machinery, and biofilms cause many persistent infections. A fundamental goal in microbiology is to understand how these interesting and important bacterial communities develop. Recently, it has become apparent that bacteria use a number of conserved design principles to build a biofilm. Namely, cells produce extracellular signals to communicate information about cell density and cell position and this information is used to regulate the temporal and spatial expression of developmental genes. This project focuses on the regulation of developmental genes in Myxococcus xanthus. When starving, M. xanthus forms a biofilm containing a thin mat of cells and multicellular fruiting body structures. A cascade of enhancer binding proteins (EBPs), which is designed to respond to a variety of extracellular signals, is used to regulate many developmental genes. The long-term goal of this project is to understand how this regulatory network coordinates developmental gene expression and, ultimately, how it promotes the assembly of a biofim. The EBP Nla4 functions at the front end of the cascade, regulating the entry into development. The aim of this project is to understand how Nla4 helps cells navigate through this critical juncture in development. Specifically, this project aims to find Nla4 target genes, to understand how Nla4 recognizes target promoters and to determine whether these target genes are important for development. It seems likely that regulatory networks analogous to the EBP cascade will be a common theme in bacteria that make biofilms, since they must also process a variety of signal information to properly regulate their developmental genes. Therefore, we believe that this project will lead to a model for gene regulation that is pertinent to many bacterial systems.