A yeast replicative helicase, Dna2 helicase, interacts with yeast FEN-1 nuclease in carrying out its essential function.
We have recently described a new helicase, the Dna2 helicase, that is essential for yeast DNA replication. We now show that the yeast FEN-1 (yFEN-1) nuclease interacts genetically and biochemically with Dna2 helicase. FEN-1 is implicated in DNA replication and repair in yeast, and the mammalian homolog of yFEN-1 (DNase IV, FEN-1, or MF1) participates in Okazaki fragment maturation. Overproduction of yFEN-1, encoded by RAD27/RTH1, suppresses the temperature-sensitive growth of dna2-1 mutants. Overproduction of Dna2 suppresses the rad27/rth1 delta temperature-sensitive growth defect. dna2-1 rad27/rth1 delta double mutants are inviable, indicating that the mutations are synthetically lethal. The genetic interactions are likely due to direct physical interaction between the two proteins, since both epitope-tagged yFEN-1 and endogenous yFEN-1 coimmunopurify with tagged Dna2. The simplest interpretation of these data is that one of the roles of Dna2 helicase is associated with processing of Okazaki fragments.
Budd
M E
ME
Braun Laboratories, California Institute of Technology, Pasadena 91125, USA.
Campbell
J L
JL
D000251:Adenosine Triphosphatases / Q000235:genetics / Q000378:metabolism*; D001483:Base Sequence; D000071877:Checkpoint Kinase 1; D004265:DNA Helicases / Q000235:genetics / Q000378:metabolism*; D004260:DNA Repair; D004261:DNA Replication; D004271:DNA, Fungal / Q000096:biosynthesis / Q000235:genetics; D004706:Endodeoxyribonucleases / Q000235:genetics / Q000378:metabolism*; D045585:Flap Endonucleases; D005800:Genes, Fungal; D009154:Mutation; D010641:Phenotype; D011494:Protein Kinases / Q000235:genetics; D012441:Saccharomyces cerevisiae / Q000201:enzymology* / Q000235:genetics / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins; D013489:Suppression, Genetic
D004271:DNA, Fungal; D029701:Saccharomyces cerevisiae Proteins; D011494:Protein Kinases; D000071877:Checkpoint Kinase 1; D004706:Endodeoxyribonucleases; D045585:Flap Endonucleases; C468323:RAD27 protein, S cerevisiae; D000251:Adenosine Triphosphatases; D004265:DNA Helicases; C410222:DNA2 protein, S cerevisiae