A novel single-stranded DNA-binding protein from the Novikoff hepatoma which stimulates DNA polymerase beta. Purification and general characterization
We have isolated and purified to homogeneity a novel single-stranded DNA-binding protein from the Novikoff hepatoma. This protein is distinguished from other eukaryotic DNA-binding proteins by binding weakly, but cooperatively, to single-stranded DNA, by its ability to partially destabilize a double...
Gespeichert in:
Veröffentlicht in: | The Journal of biological chemistry 1983-03, Vol.258 (5), p.3126-3133 |
---|---|
Hauptverfasser: | , |
Format: | Artikel |
Sprache: | eng |
Schlagworte: | |
Online-Zugang: | Volltext |
Tags: |
Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
|
Zusammenfassung: | We have isolated and purified to homogeneity a novel single-stranded DNA-binding protein from the Novikoff hepatoma. This protein is distinguished from other eukaryotic DNA-binding proteins by binding weakly, but cooperatively, to single-stranded DNA, by its ability to partially destabilize a double helix at 37 degrees C, and by its ability to stimulate DNA polymerase beta. The protein exists as a globular monomer of Mr = 48,000 and is capable of binding 45-49 nucleotides. It does not form a complex with the polymerase, but binds the DNA template, allowing an increased rate and extent of DNA synthesis. The enhancement of synthesis is greatest with larger gap-sized templates and with low polymerase concentrations. The mechanism of stimulation is thought to be due largely to placing the template strand into a conformation that facilitates rapid polymerization rather than strand displacement in advance of the polymerase. This protein has been named SSB-48. |
---|---|
ISSN: | 0021-9258 1083-351X |
DOI: | 10.1016/S0021-9258(18)32840-0 |