title: The Elg1 replication factor C-like complex functions in PCNA unloading during DNA replication.
abstract: The ring-shaped complex PCNA coordinates DNA replication, encircling DNA to act as a polymerase clamp and a sliding platform to recruit other replication proteins. PCNA is loaded onto DNA by replication factor C, but it has been unknown how PCNA is removed from DNA when Okazaki fragments are completed or the replication fork terminates. Here we show that the Elg1 replication factor C-like complex (Elg1-RLC) functions in PCNA unloading. Using an improved degron system we show that without Elg1, PCNA accumulates on Saccharomyces cerevisiae chromatin during replication. The accumulated PCNA can be removed from chromatin in vivo by switching on Elg1 expression. We find moreover that treating chromatin with purified Elg1-RLC causes PCNA unloading in vitro. Our results demonstrate that Elg1-RLC functions in unloading of both unmodified and SUMOylated PCNA during DNA replication, while the genome instability of an elg1Δ mutant suggests timely PCNA unloading is critical for chromosome maintenance.
authors.affiliation: Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, Scotland, UK.
authors.forename: Takashi
authors.initials: T
authors.lastname: Kubota
authors.forename: Kohei
authors.initials: K
authors.lastname: Nishimura
authors.forename: Masato T
authors.initials: MT
authors.lastname: Kanemaki
authors.forename: Anne D
authors.initials: AD
authors.lastname: Donaldson
mesh_terms: D002352:Carrier Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D002843:Chromatin / Q000378:metabolism; D015825:Chromosomes, Fungal / Q000378:metabolism; D004247:DNA / Q000378:metabolism; D004249:DNA Damage; D004261:DNA Replication; D004271:DNA, Fungal / Q000737:chemistry; D055786:Gene Knockout Techniques; D042822:Genomic Instability; D018809:Proliferating Cell Nuclear Antigen / Q000737:chemistry / Q000378:metabolism*; D011485:Protein Binding; D016196:S Phase; D012441:Saccharomyces cerevisiae / Q000235:genetics* / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D058207:Sumoylation; D044767:Ubiquitin-Protein Ligases / Q000235:genetics / Q000378:metabolism
chemical_list: D002352:Carrier Proteins; D002843:Chromatin; D004271:DNA, Fungal; C477609:Elg1 protein, S cerevisiae; C022262:Okazaki fragments; C546594:POL30 protein, S cerevisiae; D018809:Proliferating Cell Nuclear Antigen; D029701:Saccharomyces cerevisiae Proteins; D004247:DNA; D044767:Ubiquitin-Protein Ligases