The goal of this research is to explore similarities and differences in the translational regulation of a subunit of RNA polymerase and a ribosomal protein operon across diverse prokaryotes. The rpoS gene, encoding the alternative sigma factor sigma s, which influences bacterial virulence, is translationally regulated as a response to environmental changes in both Escherichia coli and Borrelia burgdorferi, the causative agent of Lyme disease. The roles of B. burgdorferi rpoS mRNA sequence, length, and secondary structure, and the roles of trans-acting regulators, in particular a small non-coding RNA molecule, on translational initiation events will be characterized. In E. coli, the four ribosomal proteins of the alpha operon are translationally repressed by ribosomal protein S4, one of the proteins encoded in the operon. In Prochlorococcus marinus, Synechococcus sp. WH8102 and B. burgdorferi, rpsD, encoding S4, maps outside of the operon, suggesting a different mechanism of regulation. Both in vitro assays, using cell free extracts, and in vivo expression assays will be used to identify the cis-acting and trans-acting factors important in the translational regulation of the α operon in these diverse bacteria and to elucidate their mechanism of translational regulation.
Recent Publications and Presentations
- “In Vitro Studies Examining Borrelia burgdorferi rpoS Translational Initiation and Regulation,” Joshua Linscott, Nicholas Swerdlow and Paula Schlax, National IDeA Symposium of Biomedical Research Excellence, Bethesda, MD, June 16-18, 2010.
- “Translational Initiation and Regulation of rpoS,” Joshua Linscott, Nicholas Swerdlow and Paula Schlax,Molecular Genetics of Bacteria and Phages Conference, Madison, WI, August 4-9. 2009.
- “Transcription Start Site Mapping of Essential Genes in Diverse Bacteria,” Brian St. Thomas, Joanna Mangar and Paula Schlax, MDIBL Summer Student Research Presentations, Mount Desert Island Biological Laboratories, July 28, 2009.
- “The role of transcript length in the translational regulation of rpoS, a key virulence regulator in the Lyme disease spirochete Borrelia burgdorferi,” Nick Swerdlow, Josh Linscott, P.J. Schlax, Council on Undergraduate Research, Posters on the Hill, May 2009.