{"doi":"10.1073/pnas.87.24.9712","title":"Studies on the initiation and elongation reactions in the simian virus 40 DNA replication system.","abstract":"<jats:p>The synthesis of oligoribonucleotides by DNA primase in the presence of duplex DNA containing the simian virus 40 (SV40) origin of replication was examined. Small RNA chains (10-15 nucleotides) were synthesized in the presence of the four common ribonucleoside triphosphates, SV40 large tumor antigen (T antigen), the human DNA polymerase alpha (pol alpha)-DNA primase complex, the human single-stranded DNA-binding protein (HSSB), and topoisomerase I isolated from HeLa cells. The DNA primase-catalyzed reaction showed an absolute requirement for T antigen, HSSB, and pol alpha. The requirement for HSSB was not satisfied by other SSBs that can support the T-antigen-catalyzed unwinding of DNA containing the SV40 origin of replication. Oligoribonucleotide synthesis occurred with a lag that paralleled the lag observed in DNA synthesis. These results indicate that the specificity for the HSSB in the SV40 replication reaction is due to the pol alpha-primase-mediated synthesis of the Okazaki fragments. In contrast to this specificity, the elongation of Okazaki fragments can be catalyzed by a variety of different DNA polymerases, including high levels of pol alpha, the polymerase delta holoenzyme, T4 polymerase holoenzyme, the Escherichia coli polymerase III holoenzyme, and other polymerases. These observations suggest that leading-strand synthesis in the in vitro SV40 replication system can be nonspecific.</jats:p>","journal":"Proceedings of the National Academy of Sciences","year":1990,"id":640856,"datarank":0.7266280629687888,"base_score":4.844187086458591,"endowment":4.844187086458591,"self_citation_contribution":0.7266280629687888,"citation_network_contribution":0.0,"self_endowment_contribution":0.7266280629687888,"citer_contribution":0.0,"corpus_percentile":null,"corpus_rank":null,"citation_count":126,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":null,"is_data_producer":false,"deposit_databanks":null,"is_oa":false,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":null,"fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":1665810,"name":"T Eki","orcid":null,"position":1,"is_corresponding":false},{"id":1665812,"name":"J Hurwitz","orcid":null,"position":2,"is_corresponding":false},{"id":173454,"name":"T Matsumoto","orcid":null,"position":0,"is_corresponding":false}],"reference_count":0,"raw_metadata":{"has_enrichment":true,"resolved":true,"title":"Studies on the initiation and elongation reactions in the simian virus 40 DNA replication system.","abstract":"<jats:p>The synthesis of oligoribonucleotides by DNA primase in the presence of duplex DNA containing the simian virus 40 (SV40) origin of replication was examined. Small RNA chains (10-15 nucleotides) were synthesized in the presence of the four common ribonucleoside triphosphates, SV40 large tumor antigen (T antigen), the human DNA polymerase alpha (pol alpha)-DNA primase complex, the human single-stranded DNA-binding protein (HSSB), and topoisomerase I isolated from HeLa cells. The DNA primase-catalyzed reaction showed an absolute requirement for T antigen, HSSB, and pol alpha. The requirement for HSSB was not satisfied by other SSBs that can support the T-antigen-catalyzed unwinding of DNA containing the SV40 origin of replication. Oligoribonucleotide synthesis occurred with a lag that paralleled the lag observed in DNA synthesis. These results indicate that the specificity for the HSSB in the SV40 replication reaction is due to the pol alpha-primase-mediated synthesis of the Okazaki fragments. In contrast to this specificity, the elongation of Okazaki fragments can be catalyzed by a variety of different DNA polymerases, including high levels of pol alpha, the polymerase delta holoenzyme, T4 polymerase holoenzyme, the Escherichia coli polymerase III holoenzyme, and other polymerases. These observations suggest that leading-strand synthesis in the in vitro SV40 replication system can be nonspecific.</jats:p>","is_dataset_classified":null,"base_score":4.844187086458591,"endowment":4.844187086458591,"datacite_reuse_total":0,"file_count":0,"downloads":0,"views":0,"has_version_chain":false,"is_dataset":false,"is_oa":false,"pmid":"2175912","pmcid":"PMC55243","openalex_id":"https://openalex.org/W2064495728","authors":[],"funders":[{"funder_name":"NIGMS NIH HHS","grant_id":"GM34559-07","title":null}],"total_grants":1,"fwci":12.4987,"citation_percentile":0.98793439,"influential_citations":0,"citation_trend":[{"year":2012,"count":2},{"year":2013,"count":3},{"year":2015,"count":1},{"year":2016,"count":2}],"oa_status":"green","license":null,"oa_locations":[{"url":"https://pnas.org/doi/pdf/10.1073/pnas.87.24.9712","host_type":"publisher"},{"url":"https://doi.org/10.1073/pnas.87.24.9712","host_type":"journal"},{"url":"https://pubmed.ncbi.nlm.nih.gov/2175912","host_type":"repository"},{"url":"https://www.ncbi.nlm.nih.gov/pmc/articles/55243","host_type":"repository"}],"fields_of_study":["Polyomavirus and related diseases","DNA Repair Mechanisms","Bacteriophages and microbial interactions","DNA Polymerase II","DNA Primase","DNA Replication","DNA, Viral","DNA-Binding Proteins","DNA-Directed DNA Polymerase","Escherichia coli","HeLa Cells","Humans","Kinetics","Oligoribonucleotides","RNA Nucleotidyltransferases","Simian virus 40","T-Phages"],"mesh_terms":["DNA Polymerase II","DNA-Directed DNA Polymerase","DNA Replication","DNA-Binding Proteins","DNA, Viral","Escherichia coli","HeLa Cells","Humans","Kinetics","Oligoribonucleotides","RNA Nucleotidyltransferases","Simian virus 40","T-Phages","DNA Primase","Hela Cells"],"keywords":["Okazaki fragments","Primase","DNA polymerase II","DNA polymerase","DNA replication","Biology","DNA polymerase delta","DNA clamp","DNA polymerase I","Molecular biology","Polymerase","Eukaryotic DNA replication","Replication factor C","DnaG","DNA","Biochemistry","Reverse transcriptase","RNA","Gene"],"sdg_mappings":[],"linked_datasets":[],"clinical_trials":[],"software_tools":[],"database_accessions":[],"source":"live","citation_network_status":"fetched"},"created_at":"2026-08-07T14:14:10.921693Z","pmid":null,"pmcid":null,"fwci":null,"citation_percentile":null,"influential_citations":0,"oa_status":null,"license":null,"views":0,"total_file_size_bytes":0,"version_count":0,"fair_f":null,"fair_a":null,"fair_i":null,"fair_r":null,"fair_zscore":null,"fair_rationale":null,"fair_model":null,"fair_agent_version":null,"fair_fulltext_source":null,"fair_has_llm":null,"fair_computed_at":null,"clinical_trials":[],"software_tools":[],"db_accessions":[],"linked_datasets":[],"topics":[]}