RMgmDB - Rodent Malaria genetically modified Parasites


Malaria parasiteP. berghei
DisruptedGene model (rodent): PBANKA_1218100; Gene model (P.falciparum): PF3D7_0320400; Gene product: oocyst capsule protein Cap380, putative (PbCap380, Plasmodium oocyst capsule protein)
Phenotype Oocyst; Sporozoite;
Last modified: 29 December 2009, 15:02
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) : 18248630
MR4 number
Parent parasite used to introduce the genetic modification
Rodent Malaria ParasiteP. berghei
Parent strain/lineP. berghei ANKA
Name parent line/clone P. berghei ANKA 2.34
Other information parent lineP. berghei ANKA 2.34 is a cloned, gametocyte producer line of the ANKA strain (PubMed: PMID: 15137943).
The mutant parasite was generated by
Name PI/ResearcherP. Srinivasan; M. Jacobs-Lorena
Name Group/DepartmentMalaria Research Institute, Department of Molecular Microbiology and Immunology
Name InstituteJohns Hopkins School of Public Health
Name of the mutant parasite
RMgm numberRMgm-363
Principal namePbCap380(−)
Alternative name
Standardized name
Is the mutant parasite cloned after genetic modificationYes
Asexual blood stageNot different from wild type
Gametocyte/GameteNot different from wild type
Fertilization and ookineteNot different from wild type
OocystNormal numbers of midgut ookinetes are produced. Ookinetes can invade and traverse the midgut epithelium comparable to wild type ookinetes. Ookinetes transform efficiently in oocysts but the number of oocysts declined as development proceeded. When analysed at day 15 after the infectious blood meal, neither mature oocysts nor sporozoites could be detected. In a few mosquitoes small, disintegrating oocysts were observed.
SporozoiteNo mature oocysts and (oocyst-derived) sporozoites are formed
Liver stageNot tested
Additional remarks phenotype

The mutant lacks expression of PbCap380 (Plasmodium oocyst capsule protein).

Protein (function)
Anti-PbCap380 antibody staining showed that PbCAPp380 can be detected soon after the ookinete transforms into an oocyst (36 h) and remains on the oocyst periphery till sporozoites begin to be released at around day 15. Confocal microscopy of day 15 oocysts double-labelled with anti-PbCap380 and anti-PbCSP antibodies show that PbCap380 localizes externally to the CS protein, suggesting that it is part of the protective capsule. Immuno-electron microscopy confirmed that PbCap380 localizes to the capsule.

The phenotype analyses indicate an essential role of PbCap380 for development of the oocyst and its involvement in the formation of the oocyst capsule (wall). Mutant parasites form oocysts in normal numbers but are gradually eliminated.

Additional information
Quantitative RT-PCR analysis showed that PbCap380 is expressed only during oocyst differentiation in the mosquito.
Two gene models exist: PB000071.00.0 and PB300510.00.0

Other mutants

  Disrupted: Mutant parasite with a disrupted gene
Details of the target gene
Gene Model of Rodent Parasite PBANKA_1218100
Gene Model P. falciparum ortholog PF3D7_0320400
Gene productoocyst capsule protein Cap380, putative
Gene product: Alternative namePbCap380, Plasmodium oocyst capsule protein
Details of the genetic modification
Inducable system usedNo
Additional remarks inducable system
Type of plasmid/construct usedPlasmid single 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 genePartial
Additional remarks partial/complete disruption
Selectable marker used to select the mutant parasitepbdhfr
Promoter of the selectable markerpbdhfr
Selection (positive) procedurepyrimethamine
Selection (negative) procedureNo
Additional remarks genetic modificationThe mutant has been generated using a construct that disrupt the gene by single cross-over integration (insertion vector). The disadvantage of using an insertion construct is that the construct can be removed from the genome, thereby restoring the wild type genotype.
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
Additional information primer 1IntgF
Additional information primer 2IntgR
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