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Updated: Jan 30, 2026
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Preparation of Multifunctional Silk-Based Microcapsules Loaded with DNA Plasmids Encoding RNA Aptamers and Riboswitches
Published on: October 8, 2021
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Riboswitch Signal Amplification by Controlling Plasmid Copy Number
Mohammed Dwidar1, Yohei Yokobayashi1
1Nucleic Acid Chemistry and Engineering Unit , Okinawa Institute of Science and Technology Graduate University , Onna , Okinawa 904 0495 , Japan.
ACS Synthetic Biology
|January 26, 2019
Summary
This study introduces a novel dual-riboswitch system to enhance gene expression control in synthetic biology. The innovative design significantly improves the ON/OFF ratio, addressing limitations of current riboswitch technology.
Area of Science:
- Synthetic biology
- Molecular biology
- Genetic engineering
Background:
- Riboswitches are RNA devices controlling gene expression based on chemical signals.
- Current riboswitches suffer from limited dynamic range and high OFF-state leakage.
- Synthetic riboswitches offer potential in diverse biological applications.
Purpose of the Study:
- To overcome limitations in riboswitch dynamic range and leakage.
- To develop a novel dual-riboswitch system for precise gene expression control.
- To demonstrate the utility of this system in controlling gene expression and CRISPR interference.
Main Methods:
- Designed and constructed a single-plasmid system with two theophylline-activated riboswitches.
- One riboswitch regulates the gene of interest; the other controls RepL protein for plasmid copy number.
- Applied the system to control CRISPR interference (CRISPRi) in Escherichia coli.
Main Results:
- Achieved a high ON/OFF gene expression ratio of up to 3900.
- Successfully controlled CRISPR interference targeting endogenous genes.
- Observed expected phenotypic changes in Escherichia coli.
Conclusions:
- The dual-riboswitch plasmid system significantly enhances gene expression control.
- This system effectively addresses limitations of dynamic range and leakage in riboswitches.
- The developed system is a valuable tool for synthetic biology applications, including CRISPRi.
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