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Updated: Jan 27, 2026
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Direct Restart of a Replication Fork Stalled by a Head-On RNA Polymerase
Published on: April 29, 2010
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Dynamics of Replication Fork Progression Following Helicase-Polymerase Uncoupling in Eukaryotes
Martin R G Taylor1, Joseph T P Yeeles1
1Division of Protein and Nucleic Acid Chemistry, Medical Research Council Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge, CB2 0QH, UK.
Journal of Molecular Biology
|March 22, 2019
Summary
Leading-strand polymerase stalling at DNA damage slows replication forks. Cessation of leading-strand synthesis, not coupling factors, triggers this slowdown, balancing checkpoint activation and DNA stability.
Area of Science:
- Molecular Biology
- DNA Replication
- Biochemistry
Background:
- DNA damage can stall replication forks, impacting genome integrity.
- Leading-strand synthesis is crucial for efficient replication fork progression.
Purpose of the Study:
- To investigate the molecular mechanisms underlying replication fork stalling at leading-strand DNA damage.
- To identify the key triggers and consequences of leading-strand polymerase stalling.
Main Methods:
- Biochemical approaches were employed to analyze replication fork dynamics.
- Studies focused on polymerase stalling (Pol ε, Pol δ) at various DNA lesions.
Main Results:
- Leading-strand polymerase stalling results from slower unwinding and prolonged stalled fork structures.
- Fork slowing and stalling are associated with continuous lagging-strand synthesis.
- These responses are triggered by the cessation of leading-strand polymerization, independent of specific coupling factors.
Conclusions:
- Cessation of leading-strand polymerization is a critical intrinsic response to DNA damage.
- This mechanism balances the activation of the DNA replication checkpoint with the prevention of excessive single-stranded DNA exposure.
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