RPA governs endonuclease switching during processing of Okazaki fragments in eukaryotes

摘要: Extensive work on the maturation of lagging strands during replication simian virus 40 DNA suggests that initiator RNA primers Okazaki fragments are removed by combined action two nucleases, RNase HI and Fen1, before join1,2,3,4,5. Despite well established in vitro roles these enzymes6, genetic analyses yeast revealed null mutants and/or Fen1 not lethal7,8,9, suggesting an additional enzymatic activity may be required for removal RNA. One such enzyme is Saccharomyces cerevisiae Dna2 helicase10,11,12/endonuclease12, which essential cell viability13,14 suited to removing fragments15. In addition, interacts genetically physically with several proteins involved elongation or fragments10,16. Here we show endonucleases act sequentially facilitate complete primer The sequential enzymes governed a single-stranded DNA-binding protein, protein-A (RPA). Our results demonstrate processing eukaryotes differs significantly from, more complicated than, occurring prokaryotes. We propose novel biochemical mechanism eukaryotic fragments.