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Updated: Jul 15, 2026
08:13
A Cre-Lox P Recombination Approach for the Detection of Cell Fusion In Vivo
Published on: January 4, 2012
A genomic approach to gene fusion technology
T K Van Dyk1, Y Wei, M K Hanafey
1DuPont Company, Biochemical Sciences and Engineering, Wilmington, DE 19880, USA. Tina.K.Van-Dyk@usa.dupont.com
Summary
Researchers developed a genomewide collection of Escherichia coli (E. coli) bioluminescent reporter gene fusions. This tool validates gene expression data and aids in discovering gene regulation and operons.
Area of Science:
- Microbiology
- Molecular Biology
- Genomics
Background:
- Gene expression profiling analyzes cellular responses to perturbations.
- Reporter gene technology is underutilized compared to DNA array-based methods.
- Understanding transcriptional regulation in E. coli is crucial.
Purpose of the Study:
- To create and validate a genomewide collection of E. coli bioluminescent reporter gene fusions.
- To provide an independent method for testing gene expression data.
- To demonstrate the utility of reporter gene fusions in defining operons.
Main Methods:
- Constructed a genome-registered collection of E. coli chromosomal DNA fusions to a Photorhabdus luminescens luxCDABE reporter.
- Mapped approximately 30% of E. coli's transcriptional units.
- Tested reporter fusions against known stress responses (heat shock, SOS, OxyR, SoxRS, cya/crp).
- Validated DNA microarray results using selected luxCDABE fusions.
Main Results:
- The reporter gene fusion collection accurately mirrored E. coli's transcriptional responses to various stimuli.
- Data from luxCDABE fusions confirmed or contradicted DNA microarray findings.
- Combined gene fusion and microarray data suggested a 20-gene operon for type I extracellular polysaccharide production.
Conclusions:
- The genomewide reporter gene fusion collection is a valuable tool for studying gene expression in E. coli.
- This resource serves as an independent validation for other gene expression analyses.
- Partnering reporter gene fusions with DNA microarrays enhances promoter discovery and operon definition.
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