Dual Genetic Selection of Synthetic Riboswitches in Escherichia coli

  • Yoko Nomura
  • Yohei Yokobayashi
Part of the Methods in Molecular Biology book series (MIMB, volume 1111)


This chapter describes a genetic selection strategy to engineer synthetic riboswitches that can chemically regulate gene expression in Escherichia coli. Riboswitch libraries are constructed by randomizing the nucleotides that potentially comprise an expression platform and fused to the hybrid selection/screening marker tetAgfpuv. Iterative ON and OFF selections are performed under appropriate conditions that favor the survival or the growth of the cells harboring the desired riboswitches. After the selection, rapid screening of individual riboswitch clones is performed by measuring GFPuv fluorescence without subcloning. This optimized dual genetic selection strategy can be used to rapidly develop synthetic riboswitches without detailed computational design or structural knowledge.

Key words

Riboswitch Aptamer Gene regulation RNA engineering Translational regulation 



We thank the previous members of our group, in particular, Dr. Norihito Muranaka and Dr. Vandana Sharma who contributed to the development of the dual genetic selection methods. The work was supported by National Science Foundation.


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Copyright information

© Springer Science+Business Media New York 2014

Authors and Affiliations

  • Yoko Nomura
    • 1
  • Yohei Yokobayashi
    • 1
  1. 1.Department of Biomedical EngineeringUniversity of California, DavisDavisUSA

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