Mfd Dynamically Regulates Transcription via a Release and Catch-Up Mechanism
Tung T Le1, Yi Yang1, Chuang Tan1
1Howard Hughes Medical Institute, Cornell University, Ithaca, NY 14853, USA; Physics Department & LASSP, Cornell University, Ithaca, NY 14853, USA.
Cell
|December 12, 2017
Summary
The bacterial Mfd ATPase protein patrols DNA to resolve transcription conflicts. It uses a unique "release and catch-up" mechanism to efficiently manage stalled RNA polymerases (RNAPs).
Area of Science:
- Molecular Biology
- Biochemistry
- Genetics
Background:
- The bacterial Mfd ATPase is a transcription factor.
- It resolves transcription conflicts by interacting with stalled RNA polymerases (RNAPs).
- The precise mechanism of Mfd-RNAP interaction and Mfd's preference for stalled RNAPs were unknown.
Purpose of the Study:
- To elucidate the mechanism by which Mfd ATPase interacts with stalled RNAPs.
- To understand how Mfd facilitates the resolution of transcription conflicts.
- To investigate the coordination between Mfd and RNAP during DNA processing.
Main Methods:
- Development and application of a novel real-time translocase assay.
- Observation of Mfd translocation on DNA in real-time.
- Analysis of Mfd's interaction dynamics with RNAPs under various conditions.
Main Results:
- Mfd ATPase exhibits autonomous DNA translocation.
- A "release and catch-up" mechanism enables Mfd to efficiently patrol DNA for stalled RNAPs.
- Mfd can prevent RNAP backtracking, rescue backtracked RNAPs, or dissociate RNAPs if obstacles are too severe.
Conclusions:
- Mfd ATPase employs a unique autonomous translocation mechanism for DNA patrolling.
- Mfd's actions ensure efficient RNAP management and conflict resolution.
- This study reveals a delicate coordination between Mfd and RNAP, optimizing DNA processes.
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