Figure 2From: The ArabidopsisAt1g30680 gene encodes a homologue to the phage T7 gp4 protein that has both DNA primase and DNA helicase activitiesDNA primase assay. The recombinant Twinkle homologue purified from E. coli cells was tested for DNA primase activity. Panel A, lane L (DNA single-base ladder), oligo dT9-18 included as size markers (same for panel B). Lane T, reaction products with the recombinant protein. Lane C, reaction products using a bacterial fraction with the empty vector as control. Panel B shows incorporation of primers into high molecular weight DNA in the presence (lane 6) but not the absence (lane 5) of E. coli DNA polymerase I and dNTPs. Lanes 3 and 4 are the control protein fraction in the absence (lane 3) and presence (lane 4) of DNA polymerase I and dNTPs.Back to article page