The convergence of head-on DNA unwinding forks induces helicase oligomerization and activity transition - Archive ouverte HAL Access content directly
Journal Articles Proceedings of the National Academy of Sciences of the United States of America Year : 2022

The convergence of head-on DNA unwinding forks induces helicase oligomerization and activity transition

Abstract

Significance Bloom syndrome helicase (BLM) is a multifunctional helicase that primarily catalyzes the separation of two single strands of DNA. Here, using a single-molecule optical tweezers approach combined with confocal microscopy, we monitored both the enzymatic activity and oligomeric status of BLM at the same time. Strikingly, a head-on collision of BLM-medicated DNA unwinding forks was found to effectively switch their oligomeric state and activity. Specifically, BLMs, upon collision, immediately fuse across the fork junctions and covert their activities from dsDNA unwinding to ssDNA translocation and protein displacement. These findings explain how BLM plays multiple functional roles in homologous recombination (HR). The single-molecule approach used here provides a reference model for investigating the relationship between protein oligomeric state and function.
Fichier principal
Vignette du fichier
pnas.2116462119.pdf (1.8 Mo) Télécharger le fichier
Origin : Publication funded by an institution

Dates and versions

hal-03874779 , version 1 (27-01-2023)

Identifiers

Cite

Lulu Bi, Zhenheng Qin, Teng Wang, Yanan Li, Xinshuo Jia, et al.. The convergence of head-on DNA unwinding forks induces helicase oligomerization and activity transition. Proceedings of the National Academy of Sciences of the United States of America, 2022, 119 (23), ⟨10.1073/pnas.2116462119⟩. ⟨hal-03874779⟩
17 View
8 Download

Altmetric

Share

Gmail Facebook Twitter LinkedIn More