RMgmDB - Rodent Malaria genetically modified Parasites


Malaria parasiteP. berghei
Genetic modification not successful
DisruptedGene model (rodent): PBANKA_1446100; Gene model (P.falciparum): Pf3D7_ 1231400; Gene product: membrane protein ICM1 (ICM1)
PhenotypeNo phenotype has been described
Last modified: 18 May 2021, 18:00
Successful modificationThe gene/parasite could not be changed/generated by the genetic modification.
The following genetic modifications were attempted Gene disruption
Number of attempts to introduce the genetic modification 4
Reference (PubMed-PMID number) Reference 1 (PMID number) : 33762339
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).
Attempts to generate the mutant parasite were performed by
Name PI/ResearcherBalestra AC, Brochet M
Name Group/DepartmentDepartment of Microbiology and Molecular Medicine, Faculty of Medicine
Name InstituteUniversity of Geneva

  Disrupted: Mutant parasite with a disrupted gene
Details of the target gene
Gene Model of Rodent Parasite PBANKA_1446100
Gene Model P. falciparum ortholog Pf3D7_ 1231400
Gene productmembrane protein ICM1
Gene product: Alternative nameICM1
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 usedYes
Name of PlasmoGEM construct/vectorPbGEM-265644
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 modificationThe unsuccessful attempts to disrupt this gene indicate an essential function during asexual blood-stage growth/multiplication.

From the paper:
'We identify a multipass membrane protein, termed important for calcium mobilization-1 (ICM1; Pf3D7_1231400) that interacts with and is phosphorylated by PKG in two different Plasmodium developmental stages and species. Through stage-specific knockdown and reverse genetic approaches, we show that ICM1 is essential for calcium mobilization in both the clinically relevant asexual blood stages and in gametocytes that mediate transmission to mosquitoes. Our findings highlight this putative transporter or channel as a crucial link between PKG function and calcium signaling'.
PKG is involved in release of merozoites from red blood cells and hepatocytes, induction of gametogenesis and parasite transmission upon ingestion of gametocytes by a blood-feeding mosquito, and sustaining cellular motility necessary for parasite dissemination. A major function of PKG in all these processes is the tightly regulated mobilization of calcium from intracellular stores within seconds of activation

In the paper evidence is presented that:
- ICM1 may represent a structurally divergent polytopic membrane protein with architectural similarities to mammalian channels, transporters, and IP3 receptors.
- ICM1 is phosphorylated in a PKG-dependent manner
- Stage-specific knockdown of PbICM1 reveals a crucial role in early calcium mobilization required to initiate gametogenesis
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