Multistep loading of a DNA sliding clamp onto DNA by replication factor C Journal Article

Authors: Schrecker, M.; Castaneda, J. C.; Devbhandari, S.; Kumar, C.; Remus, D.; Hite, R. K.
Article Title: Multistep loading of a DNA sliding clamp onto DNA by replication factor C
Abstract: The DNA sliding clamp proliferating cell nuclear antigen (PCNA) is an essential co-factor for many eukaryotic DNA metabolic enzymes. PCNA is loaded around DNA by the ATP-dependent clamp loader replication factor C (RFC), which acts at single-stranded (ss)/double-stranded DNA (dsDNA) junctions harboring a recessed 3' end (3' ss/dsDNA junctions) and at DNA nicks. To illuminate the loading mechanism we have investigated the structure of RFC:PCNA bound to ATPγS and 3' ss/dsDNA junctions or nicked DNA using cryogenic electron microscopy. Unexpectedly, we observe open and closed PCNA conformations in the RFC:PCNA:DNA complex, revealing that PCNA can adopt an open, planar conformation that allows direct insertion of dsDNA, and raising the question of whether PCNA ring closure is mechanistically coupled to ATP hydrolysis. By resolving multiple DNA-bound states of RFC:PCNA we observe that partial melting facilitates lateral insertion into the central channel formed by RFC:PCNA. We also resolve the Rfc1 N-terminal domain and demonstrate that its single BRCT domain participates in coordinating DNA prior to insertion into the central RFC channel, which promotes PCNA loading on the lagging strand of replication forks in vitro. Combined, our data suggest a comprehensive and fundamentally revised model for the RFC-catalyzed loading of PCNA onto DNA. © 2022, Schrecker, Castaneda et al.
Keywords: genetics; dna replication; protein conformation; metabolism; dna repair; chemistry; dna; saccharomyces cerevisiae proteins; replication factor c; adenosine triphosphate; cycline; saccharomyces cerevisiae protein; replication protein c; proliferating cell nuclear antigen; molecular biophysics; pcna; structural biology; s. cerevisiae
Journal Title: eLife
Volume: 11
ISSN: 2050-084X
Publisher: eLife Sciences Publications Ltd.  
Date Published: 2022-08-08
Start Page: e78253
Language: English
DOI: 10.7554/eLife.78253
PUBMED: 35939393
PROVIDER: scopus
PMCID: PMC9359705
Notes: Article -- Export Date: 1 September 2022 -- Source: Scopus
Citation Impact
MSK Authors
  1. Dirk Remus
    19 Remus
  2. Charanya   Kumar
    6 Kumar
  3. Richard Kevin Hite
    19 Hite