RMgmDB - Rodent Malaria genetically modified Parasites


Malaria parasiteP. berghei
DisruptedGene model (rodent): PBANKA_1018100; Gene model (P.falciparum): PF3D7_1426500; Gene product: ABC transporter G family member 2 (ABCG2)
Phenotype Gametocyte/Gamete;
Last modified: 22 June 2020, 14:03
Successful modificationThe parasite was generated by the genetic modification
The mutant contains the following genetic modification(s) Gene disruption
Reference (PubMed-PMID number) Reference 1 (PMID number) : 32445722
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/ResearcherKenthirapalan S, Maier AG
Name Group/DepartmentResearch School of Biology
Name InstituteThe Australian National University
Name of the mutant parasite
RMgm numberRMgm-4835
Principal namePbgabcg2(-)
Alternative name
Standardized name
Is the mutant parasite cloned after genetic modificationYes
Asexual blood stageNot different from wild type
Gametocyte/GameteEvidence is presented for increased gametocyte conversion rates
Fertilization and ookineteNot tested
OocystNot tested
SporozoiteNot tested
Liver stageNot tested
Additional remarks phenotype

The mutant lacks expression of ABCG2

Protein (function)
In different Plasmodium parasites 14-16 ABC-transporter genes have been identified (16 in P. falciparum, 14 in P. berghei) with one member of the ABCG subfamily (ABCG2).

Expression of PfgABCG2 of P. falciparum in the sexual stages is restricted to female gametocytes, where it localizes to a distinct single spherical structure near the apical end, termed the gametocyte-specific spot. Deletion of gABCG2 in P. falciparum results in an increase in gametocytes of both sexes and reduced levels of cholesteryl esters, diacylglycerol and triacylglycerol. These neutral lipids play a role in storing energy and building blocks for metabolic synthesis. It was, therefore, proposed that P. falciparum gABCG2 might play a role in accumulation of neutral lipids, and the gametocyte-specific spot represents a modified lipid body serving as a storage compartment for lipids that are required for parasite development in the mosquito. Access to neutral lipids in the mosquito is restricted due to the inability of both the parasite and the host to synthesize some of the neutral lipids such as cholesterol and due to competition. For instance, triacylglycerols are rapidly absorbed in the midgut, since they are a significant component for egg production. Based on sequence homology, our hypothesis was that P. berghei gABCG2 is a functional homolog of P. falciparum gABCG2. It was previously shown that P. berghei gABCG2 is dispensable for progression through the entire life cycle, in good agreement with the data on blood infection from P. falciparum

Evidence is presented for increased gametocyte conversion rates

Additional information
From the abstract:
'Here, we present detailed functional profiling of the female gametocyte-specific ATP-binding cassette transporter gABCG2 in the murine parasite P. berghei and compare our findings with data from the orthologous gene in the human parasite Plasmodium falciparum. We show that P. berghei gABCG2 is female-specific and continues to be expressed in zygotes and ookinetes. In contrast to a distinct localization to Iipid-rich gametocyte-specific spots as observed in P. falciparum, the murine malaria parasite homolog is found at the parasite plasma membrane. P. berghei lacking gABCG2 displays fast asexual blood-stage replication and increased proportions of female gametocytes, consistent with the corresponding P. falciparum knock-out phenotype.'
Cross-species replacement of gABCG2 in either the murine (RMgm-4836) or the human parasite did not restore normal growth rates, demonstrating the lack of successful complementation.

Other mutants

  Disrupted: Mutant parasite with a disrupted gene
Details of the target gene
Gene Model of Rodent Parasite PBANKA_1018100
Gene Model P. falciparum ortholog PF3D7_1426500
Gene productABC transporter G family member 2
Gene product: Alternative nameABCG2
Details of the genetic modification
Inducable system usedNo
Additional remarks inducable system
Type of plasmid/construct used(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
Partial or complete disruption of the geneComplete
Additional remarks partial/complete disruption
Selectable marker used to select the mutant parasitehdhfr
Promoter of the selectable markereef1a
Selection (positive) procedurepyrimethamine
Selection (negative) procedureNo
Additional remarks genetic modification
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