RMgmDB - Rodent Malaria genetically modified Parasites


Malaria parasiteP. berghei
MutatedGene model (rodent): PBANKA_0831000; Gene model (P.falciparum): PF3D7_0930300; Gene product: merozoite surface protein 1 (MSP1)
Details mutation: the last 330 bp of P. berghei msp1 replaced by the last 318 bp of P. vivax msp1
PhenotypeNo phenotype has been described
Last modified: 6 April 2020, 15:25
Successful modificationThe parasite was generated by the genetic modification
The mutant contains the following genetic modification(s) Gene mutation
Reference (PubMed-PMID number) Reference 1 (PMID number) : 32153555
MR4 number
Parent parasite used to introduce the genetic modification
Rodent Malaria ParasiteP. berghei
Parent strain/lineP. berghei ANKA
Name parent line/clone Not applicable
Other information parent line
The mutant parasite was generated by
Name PI/ResearcherDobrescu I, Bargieri DY
Name Group/DepartmentDepartment of Parasitology, Institute of Biomedical Sciences
Name InstituteUniversity of São Paulo
CitySão Paulo
Name of the mutant parasite
RMgm numberRMgm-4745
Principal namePb/PvMSP1(19)-ANKA
Alternative name
Standardized name
Is the mutant parasite cloned after genetic modificationYes
Asexual blood stageNot different from wild type
Gametocyte/GameteNot tested
Fertilization and ookineteNot tested
OocystNot tested
SporozoiteNot tested
Liver stageNot tested
Additional remarks phenotype

The mutant expresses a mutated msp1 gene in which the last 330 bp of P. berghei msp1 is replaced by the last 318 bp of P. vivax msp1.
The cloned PvMSP1(19) was sequenced and is identical to the sequences of P. vivax Sal-I and Belém strains.

Protein (function)

Normal blood stage growth multiplication in mice. This indicates that replacement of P. berghei ANKA or NK65 MSP119 by the P. vivax MSP119 had no impact on the parasite ability to multiply in the host blood, indicating that host cell invasion, intraerythrocytic schizogony, and merozoite egress of the hybrid mutant merozoites occur normally.

Additional information

From the Abstract:
'The Plasmodium berghei strains ANKA and NK65 were modified to express PvMSP119 instead of the endogenous PbMSP119. The hybrid parasites were used to challenge C57BL/6 or BALB/c mice immunized with PvMSP119-based vaccine formulations. The PvMSP119 was correctly expressed in the P. berghei hybrid mutant lines as confirmed by immunofluorescence using anti-PvMSP119 monoclonal antibodies and by Western blot. Replacement of the PbMSP119 by the PvMSP119 had no impact on asexual growth in vivo. High titers of specific antibodies to PvMSP119 were not sufficient to control initial parasitemia in the immunized mice, but late parasitemia control and a balanced inflammatory process protected these mice from dying, suggesting that an established immune response to PvMSP119 in this model can help immunity mounted later during infection.' 

Other mutants

  Mutated: Mutant parasite with a mutated gene
Details of the target gene
Gene Model of Rodent Parasite PBANKA_0831000
Gene Model P. falciparum ortholog PF3D7_0930300
Gene productmerozoite surface protein 1
Gene product: Alternative nameMSP1
Details of the genetic modification
Short description of the mutationthe last 330 bp of P. berghei msp1 replaced by the last 318 bp of P. vivax msp1
Inducable system usedNo
Short description of the conditional mutagenesisNot available
Additional remarks inducable system
Type of plasmid/construct(Linear) plasmid double cross-over
PlasmoGEM (Sanger) construct/vector usedNo
Modified PlasmoGEM construct/vector usedNo
Plasmid/construct map
Plasmid/construct sequence
Restriction sites to linearize plasmid
Selectable marker used to select the mutant parasitehdhfr
Promoter of the selectable markernot known
Selection (positive) procedurepyrimethamine
Selection (negative) procedureNo
Additional remarks genetic modificationTo generate the pPb/PvMSP119 plasmids, 1,526 bp of the sequence upstream the P. berghei ANKA MSP119 (nucleotides 3,521–5,046 of the genomic sequence of PBANKA_0831000) and the first 611 bp of the msp1 3′UTR were cloned flanking the sequence of the P. vivax MSP1(19) (318 bp, amplified from DNA of parasites isolated from a Brazilian patient and kindly provided by Dr. Marcelo U. Ferreira) followed by the P. berghei trap 3′UTR (600 bp) and a human Dihydrofolate Reductase cassette (hDHFR) using as background the pBlueScript (pBS-SK+) vector. The cloned PvMSP1(19) was sequenced and is identic to the sequences of P. vivax Sal-I and Belém strains. For transfections of the P. berghei NK65 line, a Green Fluorescent Protein (GFP) cassette was inserted between the hDHFR cassette and the msp1 3′UTR sequence in the pPb/PvMSP1(19) plasmid at SmaI site. The final vectors contain two homologous regions to target integration by double crossover at the P. berghei MSP1 locus replacing the endogenous MSP1(19) by the P. vivax MSP1(19) sequence.
Additional remarks selection procedure
Primer information: Primers used for amplification of the target sequences  Click to view information
Primer information: Primers used for amplification of the target sequences  Click to hide information
Sequence Primer 1
Additional information primer 1
Sequence Primer 2
Additional information primer 2
Sequence Primer 3
Additional information primer 3
Sequence Primer 4
Additional information primer 4
Sequence Primer 5
Additional information primer 5
Sequence Primer 6
Additional information primer 6