Studying gene expression: database searches and promoter fusions to investigate transcriptional regulation in bacteria.

A laboratory project was designed to illustrate how to search biological databases and utilize the information provided by these resources to investigate transcriptional regulation in Escherichia coli. The students searched several databases (NCBI Genomes, RegulonDB and EcoCyc) to learn about gene function, regulation, and the organization of transcriptional units. A fluorometer and GFP promoter fusions were used to obtain fluorescence data and measure changes in transcriptional activity. The class designed and performed experiments to investigate the regulation of genes necessary for biosynthesis of amino acids and how expression is affected by environmental signals and transcriptional regulators. Assessment data showed that this activity enhanced students' knowledge of databases, reporter genes and transcriptional regulation.