DNA 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.
Diray-Arce et al. BMC Plant Biology 2013 13:36 doi:10.1186/1471-2229-13-36