Related Experiment Video
Updated: Oct 30, 2025
07:46
CRISPR/Cas9 Editing of the C. elegans rbm-3.2 Gene using the dpy-10 Co-CRISPR Screening Marker and Assembled Ribonucleoprotein Complexes.
Published on: December 11, 2020
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Highly Efficient CRISPR-Mediated Base Editing in Sinorhizobium meliloti
Longxiang Wang1, Yuan Xiao2, Xiaowei Wei2
1State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China.
Frontiers in Microbiology
|July 5, 2021
Summary
New CRISPR-based base editing tools precisely modify rhizobial genes. These adenine, cytidine, and guanine base editors accelerate functional genomics and genome manipulation in symbiotic nitrogen fixation (SNF) bacteria.
Area of Science:
- Microbiology
- Molecular Biology
- Genetics
Background:
- Rhizobia are crucial soil bacteria for symbiotic nitrogen fixation (SNF) in legumes.
- Existing genetic manipulation methods in *Sinorhizobium meliloti* are inefficient and labor-intensive.
Purpose of the Study:
- To develop precise and efficient gene modification tools for rhizobia using CRISPR/Cas9.
- To establish adenine, cytidine, and guanine base editing systems for *Sinorhizobium meliloti*.
Main Methods:
- Development of an adenine base editor (ABE) by fusing Cas9 nickase to adenine deaminase.
- Engineering of a cytidine base editor (CBE) and a guanine base editor (GBE) using modified deaminases.
- Utilizing Golden Gate Assembly for assembling multiple synthetic guide RNA (sgRNA) cassettes for multigene editing.
Main Results:
- ABE enabled precise adenine-to-guanine transitions without double-strand breaks (DSB).
- CBE and GBE facilitated cytidine-to-thymine and cytidine-to-guanine modifications, respectively.
- The developed base editors allow for simultaneous multigene mutations or disruptions.
Conclusions:
- CRISPR-mediated base editing offers precise and efficient genome manipulation in rhizobia.
- These tools will significantly accelerate functional genomics studies in rhizobia.
- The new methods overcome limitations of traditional genetic manipulation techniques.
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