Coordinating Developmental Gene Expression in Myxococcus xanthus

Syracuse University, Syracuse NY

Investigators

Abstract

Anthony G. Garza IOS-0950976 Coordinating 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.