RMgmDB - Rodent Malaria genetically modified Parasites


Malaria parasiteP. yoelii
DisruptedGene model (rodent): PY17X_0415800; Gene model (P.falciparum): PF3D7_0315200; Gene product: circumsporozoite- and TRAP-related protein (CTRP)
Phenotype Fertilization and ookinete; Oocyst;
Last modified: 29 July 2021, 14:17
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) : 34301597
MR4 number
Parent parasite used to introduce the genetic modification
Rodent Malaria ParasiteP. yoelii
Parent strain/lineP. y. yoelii 17XNL
Name parent line/clone Not applicable
Other information parent line
The mutant parasite was generated by
Name PI/ResearcherYang Z, Yuan J
Name Group/DepartmentState Key Laboratory of Cellular Stress Biology, Innovation Center for Cell Signal Network, School o
Name InstituteXiamen University
CityXiamen, Fujian
Name of the mutant parasite
RMgm numberRMgm-5051
Principal nameΔctrp
Alternative name
Standardized name
Is the mutant parasite cloned after genetic modificationNo
Asexual blood stageNot tested
Gametocyte/GameteNot tested
Fertilization and ookineteOokinetes are formed but no traversal through mosquito midgut cells. Motility of ookinetes is impaired.
OocystOokinetes are formed but no traversal through mosquito midgut cells. Motility of ookinetes is impaired.
SporozoiteNot tested
Liver stageNot tested
Additional remarks phenotype

The mutant lacks expression of CTRP
The mutant has been generated using CRISPR/cas9 genome editing (using constructs as described for mutant RMgm-1095

Protein (function)
CTRP is a type 1 transmembrane protein, containing two adhesive domains in its extracellular portion, an A-domain of von Willebrand factor and a thrombospondin type I repeat (TSR, TSP). CTRP has six tandemly arrayed A domains followed by seven TSP type 1-like domains. CTRP is located in the micronemes of ookinetes. This structure is similar to that of TRAP (PF13_0201; PB000374.03.0), a malaria sporozoite protein critical for sporozoite motility and invasion into host cells.
CTRP plays a role in the motility of ookinetes and invasion of midgut epithelial cells.

Ookinetes are formed but no traversal through mosquito midgut cells. Motility of ookinetes is impaired. 

Additional information

Other mutants


  Disrupted: Mutant parasite with a disrupted gene
Details of the target gene
Gene Model of Rodent Parasite PY17X_0415800
Gene Model P. falciparum ortholog PF3D7_0315200
Gene productcircumsporozoite- and TRAP-related protein
Gene product: Alternative nameCTRP
Details of the genetic modification
Inducable system usedNo
Additional remarks inducable system
Type of plasmid/construct usedCRISPR/Cas9 construct: integration through double strand break repair
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/yfcu
Promoter of the selectable markereef1a
Selection (positive) procedurepyrimethamine
Selection (negative) procedureNo
Additional remarks genetic modificationCRISPR-Cas9 plasmid pYCm was used for all the parasite genetic modification. To construct vectors for gene editing, we amplified 5′ and 3′ genomic sequence (400 to 500 bp) of target genes as homologous arms using specific primers and inserted the sequences into specific restriction sites in pYCm. Oligonucleotides for single guide RNAs (sgRNAs) were mixed in pairs, denatured at 95°C for 3 min, annealed at room temperature for 5 min, and ligated into pYCm. The sgRNAs were designed to target the coding region of a gene using the online program EuPaGDT. DNA fragments encoding 6HA, 4Myc, 3V5, and GFP or mCherry were inserted between the left and right arms in frame with the gene of interest. For each gene, two sgRNAs were designed to target sites close to the C- or N-terminal part of the coding region. Infected red blood cells (iRBCs) were electroporated with 5 to 10 μg of plasmid DNA using the Lonza Nucleofector . Transfected parasites were immediately intravenously injected into a naïve mouse and were exposed to pyrimethamine (6 mg/ml) 24 hours after transfection.
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