Melanie Filiatrault

Melanie Filiatrault  is a Research Molecular Biologist, at the USDA-ARS Emerging Pests and Pathogens Research Unite, Ithaca, NY. Visit Melanie's USDA-ARS profile.

The broad objective of my research is to decipher molecular mechanisms of gene regulation, specifically involving virulence-related genes, in the important model organism Pseudomonas syringae to understand how the bacterium responds to environmental signals on a global scale.  We are using several approaches within our research group (transcriptomics, proteomics and metabolomics) to evaluate global gene regulation in P. syringae.  One aim of the research project is to develop high-throughput approaches that will precisely identify transcription start sites and assign genes to transcriptional units.  These efforts will aid in genome annotation by providing experimental evidence for transcriptional activity of genes classified as “hypothetical” and also may identify transcripts from intergenic regions.  In addition, these genome-scale strategies will delineate promoter sequences, promoter classes, and identify those genes that are co-regulated. These studies will help to provide critical information for a more complete transcriptome analysis of P. syringae which ultimately will help in understanding the pathogenesis of this bacterium. 

Additionally, we are characterizing small non-coding RNAs and RNA binding proteins in gene regulation of P. syringae.  Small RNAs have been demonstrated to play important regulatory roles in bacterial stress responses to diverse environmental signals, such as changes in temperature, osmolarity, iron, and oxidative stress. They are also important components of many regulatory pathways and have been shown to have key roles in regulation of factors important for virulence.  To date, only a few small RNAs and RNA binding proteins have been described in the literature for P. syringae.  Using several global approaches, which include a combination of biocomputational methods, molecular biology, and high throughput sequencing, we are identifying and characterizing small non-coding RNAs of P. syringae.  These studies will aid in the understanding of global gene regulation in P. syringae and provide data for other Pseudomonads and plant pathogens.