1. Asymmetric nucleosome PARylation at DNA breaks mediates directional nucleosome sliding by ALC1
- Author
-
Bacic, Luka, Gaullier, Guillaume, Mohapatra, Jugal, Mao, Guanzhong, Brackmann, Klaus, Panfilov, Mikhail, Liszczak, Glen, Sabantsev, Anton, Deindl, Sebastian, Bacic, Luka, Gaullier, Guillaume, Mohapatra, Jugal, Mao, Guanzhong, Brackmann, Klaus, Panfilov, Mikhail, Liszczak, Glen, Sabantsev, Anton, and Deindl, Sebastian
- Abstract
The chromatin remodeler ALC1 is activated by DNA damage-induced poly(ADP-ribose) deposited by PARP1/PARP2 and their co-factor HPF1. ALC1 has emerged as a cancer drug target, but how it is recruited to ADP-ribosylated nucleosomes to affect their positioning near DNA breaks is unknown. Here we find that PARP1/HPF1 preferentially initiates ADP-ribosylation on the histone H2B tail closest to the DNA break. To dissect the consequences of such asymmetry, we generate nucleosomes with a defined ADP-ribosylated H2B tail on one side only. The cryo-electron microscopy structure of ALC1 bound to such an asymmetric nucleosome indicates preferential engagement on one side. Using single-molecule FRET, we demonstrate that this asymmetric recruitment gives rise to directed sliding away from the DNA linker closest to the ADP-ribosylation site. Our data suggest a mechanism by which ALC1 slides nucleosomes away from a DNA break to render it more accessible to repair factors., Authors in the list of papers of Luka Bacic's thesis: Bacic, L., Gaullier, G., Mohapatra, J., Sabantsev, A., Mao, G., Liszczak, G., & Deindl, S.
- Published
- 2024
- Full Text
- View/download PDF