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A Fluorescence-based Method to Study Bacterial Gene Regulation in Infected Tissues
Published on: February 19, 2019
Quantifying translational coupling in E. coli synthetic operons using RBS modulation and fluorescent reporters
Ayelet Levin-Karp1, Uri Barenholz, Tasneem Bareia
1Department of Plant Sciences, Weizmann Institute of Science , Rehovot 76100, Israel.
ACS Synthetic Biology
|May 10, 2013
Summary
Translational coupling, the link between gene translation rates in operons, was quantified in E. coli synthetic operons. Gene expression enhancement varied over 10-fold, influenced by upstream gene sequence and intergenic distance.
Area of Science:
- Molecular Biology
- Systems Biology
- Synthetic Biology
Background:
- Translational coupling describes the interdependence of translation efficiency between adjacent genes in an operon.
- Previous studies observed translational coupling in prokaryotes but lacked quantitative characterization of its modulation range and governing factors.
Purpose of the Study:
- To systematically quantify and characterize translational coupling in synthetic Escherichia coli (E. coli) operons.
- To investigate the factors influencing the degree of translational coupling, including upstream gene sequence and intergenic distance.
Main Methods:
- Utilized a library of plasmids with fluorescent reporter genes in E. coli synthetic operons.
- Employed a range of ribosome binding site (RBS) sequences to control gene expression.
- Quantified translational coupling by measuring how upstream gene translation rate affects downstream gene expression.
Main Results:
- Downstream gene expression was enhanced by upstream gene expression through translational coupling, with enhancement levels ranging from minimal to over 10-fold.
- The level of translational coupling was comparable between the second and third gene positions within the synthetic operons.
- Translational coupling strength was found to be dependent on the distance between the upstream gene's stop codon and the downstream gene's start codon.
Conclusions:
- This study provides the first systematic and quantitative characterization of translational coupling in synthetic E. coli operons.
- The findings offer insights into the mechanisms of translational expression modulation.
- The quantitative data can aid in the precise manipulation of gene expression for synthetic biology applications.
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