Honors Thesis Archive

Author	Brian R. Mann
Additional Authors	Pete Chandrangsu, Justin Lemke, and Richard Gourse
Title	The Omega Subunit of RNA Polymerase: Identification and Regulation of the rpoZ Promoter in Escherichia coli
Department	Biochemistry/Molecular Biology
Advisor	Margaret Goodman
Year	2010
Honors	University Honors
Full Text	View Thesis (1377 KB) At the author's request, an electronic copy of this thesis is only available to on-campus users.
Abstract	The omega subunit (ω) is one of five proteins in bacterial RNA polymerase: α₁, α₂, β, β', and ω. Omega is transcribed from the rpoZ gene in the spoT operon, but little is known about the ω promoter region or the exact start site of rpoZ transcription in Escherichia coli. Previous S1 nuclease mapping of the rpoZ intergenic region identified a possible ω promoter that was found to have surprisingly low activity by the Gourse lab. Reanalysis of the rpoZ intergenic region in vivo and in vitro via primer extension identified an alternative promoter but no obvious -10 or -35 hexamer. Another possibility is that part of rpoZ expression is the result of read-through from the upstream gmk gene. Mapping of the gmk intergenic region by primer extension identified start sites at five possible positions. Future analyses of the ω subunit will confirm the sequences of the rpoZ and gmk promoters and assess the associated transcriptional regulation.