matt.traxler - Matt Traxler Graduate Student (PhD) of Microbiology

Research:

I'm currently in my final year of graduate school at the University of Oklahoma in the laboratory of Dr. Tyrrell Conway. My research is focused on understanding global transcription patterns in E. coli in response to stress. Specifically, I'm interested in regulation by the small molecule ppGpp. As the number of genes regulated by ppGpp is extremely large, I am interested in delineating the sub-networks which ultimately achieve the fine-tuned response to any given stressor. Microarrays have been my principal tool to establish the physiological and regulatory processes encompassed by the stringent response to carbon and amino acid starvation.

My recent paper in Molecular Microbiology was featured on the cover: High-throughput analysis of the stringent response. Pretty exciting, no?

Future plans:

I am currently looking for a post-doctoral position. My long-term goal is to stay in academia. My interests lie in basic research, with microbial regulatory/developmental pathways as a focus. Please email me at: mtraxler@ou.edu

Publications:

M.F. Traxler, et. al. 2008. The global, ppGpp-mediated stringent response to amino acid starvation in Escherichia coli. Mol. Microbiol. 2008. 68(5): 1128-48.

In my latest paper, we describe the physiological processes which make up the stringent response to isoleucine starvation. The micrograph at right was taken from a series which is presented in the paper. The relAspoT mutant cells (pictured) are much larger than the WT at all time points tested. This phenotype correlated with aberrant expression of a large number of genes involved in macromolecular synthesis of many types.

M.F. Traxler et al. 2006. Guanosine 3', 5'-bispyrophosphate coordinates global gene expression during glucose-lactose diauxie in Escherichia coli. Proc. Natl. Acad. Sci. USA. 103:2374-2379.

In my first paper, we used the classic glucose-lactose diauxie experimental system to examine the role of ppGpp in controlling gene expression in response to carbon starvation. We found that diverse regulatory networks, including the general stress response and carbon scavenging require ppGpp for their efficient induction. The graph at right shows the dampened global response in the relA mutant.

E-ring Web tool:

This is a tool that I worked with Joe Grissom (OU Bioinformatics Core) to create. It's for visualizing and analyzing microarray data in the context of known genetic regulatory relationships. The software generates circular heatmaps from microarray data with regulatory relationships between genes illustrated as connections inside the aperture of the circle. Have fun by uploading your own E. coli data to it, or look at some of our data. It's freely available here on our website.