Sie befinden Sich nicht im Netzwerk der Universität Paderborn. Der Zugriff auf elektronische Ressourcen ist gegebenenfalls nur via VPN oder Shibboleth (DFN-AAI) möglich. mehr Informationen...
Reconstitution of complete SV40 DNA replication with purified replication factors
Ist Teil von
The Journal of biological chemistry, 1994-04, Vol.269 (14), p.10923-10934
Ort / Verlag
Bethesda, MD: American Society for Biochemistry and Molecular Biology
Erscheinungsjahr
1994
Link zum Volltext
Quelle
MEDLINE
Beschreibungen/Notizen
The identification and purification of human cell proteins required for the production of form I DNA following DNA replication
from the simian virus 40 (SV40) origin is described. Using these proteins, complete SV40 DNA replication was reconstituted
with only purified DNA replication factors: SV40 large tumor antigen (TAg), replication protein A (RPA), DNA topoisomerases
I and II, DNA polymerase alpha-primase, replication factor C (RFC), the proliferating cell nuclear antigen (PCNA), DNA polymerase
delta, maturation factor 1 (MF1), and DNA ligase I. MF1, a 5' to 3' exonuclease and DNA ligase I were both identified as essential
components for production of covalently closed circular relaxed (form I) DNA. MF1 is probably the same exonuclease previously
shown by others to function during DNA synthesis on artificial DNA templates or in conjunction with DNA polymerase alpha from
the SV40 origin. Combined with these previous studies, our results suggest that MF1 functions to remove an RNA primer attached
to every Okazaki fragment during lagging strand DNA synthesis. Interestingly, whereas mammalian DNA ligase I functioned in
the reconstituted replication system, mammalian DNA ligase III did not substitute and the phage T4 DNA ligase functioned inefficiently,
suggesting that DNA ligase I has a specific role as a replicative DNA ligase in eukaryotic cells.