CAREER: Characterization of Transcriptional Activators that Regulate Emergent Behavior

Syracuse University, Syracuse NY

Investigators

Abstract

Myxococcus xanthus is a novel model for system-level study of control mechanisms for emergent behavior, and thus the selective advantages of cooperation and of concomitant loss of cellular autonomy. A swarm of M. xanthus is a population of millions of individual autonomous cells that function together as a single machine, coordinating movement through signals and creating dynamic patterns in response to environmental cues, a process called self-organization (SO). One such response, called development, is controlled through a cascade of transcriptional regulators (TRs), which are proteins that activate or deactivate other genes. All SO in M. xanthus could be under this type of control. Two distinct SO behaviors have already been quantified: development, a starvation response in which cells coordinate to form fruiting bodies, and tracking, directed movement of a swarm toward a nutrient source. Mutant strains were created for each of 310 TRs, and those specific for development or tracking were selected, using microarrays to identify the genes likely to be affected by each TR. Candidate genes were then disrupted to confirm the predicted functional associations. The goal of this project is to understand the role of TRs in controlling bacterial SO, using an approach that integrates genomics, computer analysis, automated microscopy, and experimental genetics to identify and characterize genetic control of two distinct emergent behaviors in M. xanthus. This project offers undergraduates, graduates and post-doctoral researchers unique opportunities to deepen their theoretical understanding of biology while gaining critical computer skills. This work is the foundation for Dr. Welch's career research goal to identify and articulate the genetic networks that control multicellular behavior, ultimately yielding critical insights into the origins of multicellularity and genetic control of formation of 3-dimensional structures.