title: The ring-type polymerase sliding clamp family.
abstract: Ring-type polymerases consist of a DNA polymerase, a ring-shaped sliding clamp protein and a clamp-loading complex. Sliding clamp proteins are found in all organisms and are called proliferating cell nuclear antigen (PCNA) in eukaryotes and the beta clamp in prokaryotes. Both PCNA and beta form a ring around DNA, which is made up of two subunits of three domains each in beta but three subunits of two domains each in PCNA. Despite this difference and a lack of detectable sequence homology, the structures of the two rings are very similar. The sliding clamp slides along DNA and tethers the polymerase to the DNA, enabling rapid and processive DNA replication.
authors.affiliation: Howard Hughes Medical Institute and Rockefeller University, 1230 York Avenue, New York, NY 10021, USA. bruck@mod.rockefeller.edu
authors.forename: I
authors.initials: I
authors.lastname: Bruck
authors.forename: M
authors.initials: M
authors.lastname: O'Donnell
mesh_terms: D000818:Animals; D004247:DNA / Q000235:genetics / Q000378:metabolism; D004261:DNA Replication / Q000235:genetics; D004259:DNA-Directed DNA Polymerase / Q000235:genetics* / Q000378:metabolism; D019143:Evolution, Molecular; D006801:Humans; D008954:Models, Biological; D018809:Proliferating Cell Nuclear Antigen / Q000235:genetics* / Q000378:metabolism
chemical_list: D018809:Proliferating Cell Nuclear Antigen; D004247:DNA; C023140:DNA replicase; D004259:DNA-Directed DNA Polymerase