Download MendeleyAutoinhibition imposed by a large conformational switch of INO80 regulates nucleosome positioning.
Kaur, U., Wu, H., Cheng, Y., Narlikar, G.J.(2025) Science 389: eadr3831-eadr3831
- PubMed: 40674492
- DOI: https://doi.org/10.1126/science.adr3831
- Primary Citation of Related Structures:
9C9G, 9C9S, 9C9T, 9C9X, 9C9Z, 9CAN, 9CAT, 9CAU, 9CB7, 9CCD - PubMed Abstract:
Increasing the flanking DNA from 40 to 80 base pairs (bp) causes ~100-fold faster nucleosome sliding by INO80. A prevalent hypothesis posits that the Arp8 module within INO80 enables a ruler-like activity. Using cryogenic electron microscopy, we show that on nucleosomes with 40 bp of flanking DNA, the Arp8 module rotates 180° away from the DNA. Deleting the Arp8 module enables rapid sliding irrespective of flanking DNA length. Thus, rather than enabling a ruler-like activity, the Arp8 module acts as a brake on INO80 remodeling when flanking DNA is short. This autoinhibition-based mechanism has broad implications for understanding how primitive nucleosome mobilization enzymes may have evolved into sophisticated remodelers.
- Department of Biochemistry and Biophysics, University of California San Francisco, San Francisco, CA, USA.
Organizational Affiliation:
