Download MendeleyStructural and molecular basis of PCNA-activated FAN1 nuclease function in DNA repair.
Li, F., Phadte, A.S., Bhatia, M., Barndt, S., Monte Carlo Iii, A.R., Hou, C.D., Yang, R., Strock, S., Pluciennik, A.(2025) Nat Commun 16: 4411-4411
- PubMed: 40368897
- DOI: https://doi.org/10.1038/s41467-025-59323-y
- Primary Citation of Related Structures:
9CG4, 9CHM, 9CL7, 9CMA - PubMed Abstract:
FAN1 is a DNA dependent nuclease whose proper function is essential for maintaining human health. For example, a genetic variant in FAN1, Arg507 to His hastens onset of Huntington's disease, a repeat expansion disorder for which there is no cure. How the Arg507His mutation affects FAN1 structure and enzymatic function is unknown. Using cryo-EM and biochemistry, we have discovered that FAN1 arginine 507 is critical for its interaction with PCNA, and mutation of Arg507 to His attenuates assembly of the FAN1-PCNA complex on a disease-relevant extrahelical DNA extrusions formed within DNA repeats. This mutation concomitantly abolishes PCNA-FAN1-dependent cleavage of such extrusions, thus unraveling the molecular basis for a specific mutation in FAN1 that dramatically hastens the onset of Huntington's disease. These results underscore the importance of PCNA to the genome stabilizing function of FAN1.
- Department of Biochemistry and Molecular Biology, Thomas Jefferson University, Philadelphia, PA, USA.
Organizational Affiliation:
