Journal article
Replication protein A modulates its interface with the primed DNA template during RNA–DNA primer elongation in replicating SV40 chromosomes
Nucleic acids research, Vol.29(18), pp.3892-3899
09/15/2001
DOI: 10.1093/nar/29.18.3892
PMCID: PMC55912
PMID: 11557822
Abstract
The eukaryal single-stranded DNA binding protein replication
protein A (RPA) binds short oligonucleotides with high affinity
but exhibits low cooperativity in binding longer templates, opposite
to prokaryal counterparts. This discrepancy could reflect the smaller
size of the replicative template portion availed to RPA. According
to current models, this portion accommodates an RNA–DNA
primer (RDP) of <40 nt (nested discontinuity) or a several-fold
longer Okazaki fragment (initiation zone). Previous
in
situ
UV-crosslinking revealed that RPA also interacts with
nascent DNA, especially growing RDPs. Here we compare nascent SV40
DNA chains UV-crosslinked to the middle and large RPA subunits and
use the data to re-examine the two models. The middle subunit interacted
with the nascent chains after a few DNA residues were added to the
RNA primer while the large subunit became accessible after extension by
several more. Upon RDP maturation, the middle subunit disengaged
while the large subunit remained accessible during further limited
extension. A corresponding shift in preference in favor of the large subunit
has been reported for purified RPA and synthetic gapped duplexes
upon reduction of the gap from 19 to 9 nt. Combined, these facts
support the proposal that the mature RDP faces downstream a correspondingly
small gap, possibly created by removal of the RNA primer moiety
from an adjacent, previously synthesized RDP (nested discontinuity) but
insufficient for continuous elongation of the RDP into an Okazaki
fragment (initiation zone).
Details
- Title: Subtitle
- Replication protein A modulates its interface with the primed DNA template during RNA–DNA primer elongation in replicating SV40 chromosomes
- Creators
- Gilad Mass - Department of Biochemistry, Tel Aviv University, Ramat Aviv, 69978 IsraelTamar Nethanel - Department of Biochemistry, Tel Aviv University, Ramat Aviv, 69978 IsraelOlga I Lavrik - Department of Biochemistry, Tel Aviv University, Ramat Aviv, 69978 IsraelMarc S Wold - Department of Biochemistry, Tel Aviv University, Ramat Aviv, 69978 IsraelGabriel Kaufmann - Department of Biochemistry, Tel Aviv University, Ramat Aviv, 69978 Israel
- Resource Type
- Journal article
- Publication Details
- Nucleic acids research, Vol.29(18), pp.3892-3899
- Publisher
- Oxford University Press; Oxford, UK
- DOI
- 10.1093/nar/29.18.3892
- PMID
- 11557822
- PMCID
- PMC55912
- ISSN
- 0305-1048
- eISSN
- 1362-4962
- Language
- English
- Date published
- 09/15/2001
- Academic Unit
- Radiation Oncology; Biochemistry and Molecular Biology
- Record Identifier
- 9984024416902771
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