1G5DiCre is a genetically modifed parasite clone (on the 3D7 background) in which the SERA5 gene has been modified by single crossover homologous recombination to reconstitute a chimeric (partly recodonised) gene which encodes the wild-type protein. An introduced DiCre cassette lies just downstream of the chimeric SERA5 gene. These parasites therefore constitutively express the DiCre proteins and so can be used to flox any gene. Note that they contain a single residual loxP site just downstream of the modified SERA5 gene. Plasmid pHH1-SERA5del3preDiCre. This is designed to target any P. falciparum gene in the 1G5DiCre parasite clone, introducing a floxed 3' UTR. Following single-crossover integration into the 1G5DiCre genome, induction of DiCre activity by rapamycin treatment (100 nM final concentration for 2-4 h) will result in excision of the introduced PbDT 3' UTR. The plasmid can be modified to target any gene. To do this, simply replace the existing SERA5 targeting sequence with a targeting sequence of choice, using the unique XhoI site plus one of the upstream HpaI or AflII sites.
Dr. Mike Blackman
UK Biosafety level:
Please state in any acknowledgements, "Plasmodium falciparum 1G5DiCre was obtained from The European Malaria Reagent Repository (http://www.malariaresearch.eu)". It is a condition of the supply of this reagent that you also cite the reference and source given above in any publication.