Regulation of Pfh1 helicase activity by nucleic acid interactions and mitochondrial SSB - PubMed
5 hours ago
- #Pfh1 helicase
- #mitochondrial SSB interactions
- #DNA unwinding kinetics
- Pfh1 helicase operates through unwinding-rewinding cycles at DNA forks, optimizing ATP usage.
- Interactions with translocating strand affect ATP affinity; interactions with displaced strand control unwinding speed.
- spRim1 binding to displaced strand disrupts interactions, increasing unwinding velocity.
- Unwinding processivity is limited to ~20 bp before transition to rewinding.
- Rewinding is ATP-dependent and incompatible with strand switching; ATP turnover modulates DNA contacts and rewinding rate.
- spRim1 accelerates rewinding by competing with helicase-DNA interactions and aids recovery of active unwinding conformation.
- Pfh1 balances unwinding and rewinding via coordinated ATP-dependent strand interactions, offering insights into Pif1-family regulation.