RMgmDB - Rodent Malaria genetically modified Parasites

Summary

RMgm-1470
Malaria parasiteP. berghei
Genotype
DisruptedGene model (rodent): PBANKA_0512000; Gene model (P.falciparum): PF3D7_1027900; Gene product: palmitoyltransferase DHHC10, putative (DHHC10)
Transgene
Transgene not Plasmodium: A fusion of GFP (gfp-mu3) and Luciferase Firefly (LucIAV)
Promoter: Gene model: PBANKA_1133300; Gene model (P.falciparum): PF3D7_1357100; Gene product: elongation factor 1-alpha (eef1a)
3'UTR: Gene model: PBANKA_0719300; Gene product: bifunctional dihydrofolate reductase-thymidylate synthase, putative (dhfr/ts)
Replacement locus: Gene model: PBANKA_0306000; Gene product: 6-cysteine protein (230p)
Phenotype Fertilization and ookinete; Oocyst; Sporozoite;
Last modified: 30 June 2016, 16:03
  *RMgm-1470
Successful modificationThe parasite was generated by the genetic modification
The mutant contains the following genetic modification(s) Gene disruption, Introduction of a transgene
Reference (PubMed-PMID number) Reference 1 (PMID number) : 27303037
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 676m1cl1 (RMgm-29)
Other information parent line676m1cl1 (RMgm-29) is a reference ANKA mutant line which expresses GFP-luciferase under control of a constitutive promoter. This reference line does not contain a drug-selectable marker (PubMed: PMID: 16242190).
The mutant parasite was generated by
Name PI/ResearcherSantos JM; Janse CJ; Mair GR
Name Group/DepartmentParasitology, Department of Infectious Diseases
Name InstituteUniversity of Heidelberg Medical School
CityHeidelberg
CountryGermany
Name of the mutant parasite
RMgm numberRMgm-1470
Principal name2365cl2
Alternative nameΔdhhc10-b
Standardized name
Is the mutant parasite cloned after genetic modificationYes
Phenotype
Asexual blood stageNot different from wild type
Gametocyte/GameteNot different from wild type
Fertilization and ookineteNormal numbers of gametocytes are produced. Normal fertilisation rate and ookinete production. Ookinetes however lack crystalloids (crystalloid body; crystalloid organelle).
OocystNormal numbers of oocysts are produced. However, oocysts fail to produce sporozoites
SporozoiteNo sporozoites are formed
Liver stageNot tested
Additional remarks phenotype

Mutant/mutation

The mutant lacks expression of DHHC10 and expresses a fusion protein of GFP and luciferase under the constitutive eef1a promoter

Protein (function)
Many proteins are post-translationally modified by the addition of lipids. Palmitoylation results in the addition of a C-16 fatty acid to a cysteine residue within a given protein. Palmitoylation is reversible and thus can dynamically regulate a protein’s subcellular localization, gene expression and activity.
Blocking palmitoylation in P. falciparum with 2-bromopalmitate (2-BMP) results in a complete failure to develop merozoites during the blood stage of the life cycle. Preventing palmitoylation of proteins through targeted mutagenesis of cysteine residues within the modification target results in the mis-localization of proteins found in the inner membrane complex (IMC).
The palmitoylation reaction is catalysed by TM-spanning enzymes called palmitoyl-S-acyl-transferases (PAT). One family of PATs is characterised by the presence of a conserved DH(H/Y)C motif, and certain apicomplexan organisms express more than 10 individual S-acyltransferases. They differ in localisation and timing of expression, and therefore are likely to modify distinct protein populations and biological functions.
The global extent of palmitoylation in asexual blood stages of P. falciparum comprises several hundred proteins; they include factors involved in gliding motility, invasion, adhesion, IMC function, signalling, protein transport and proteolytic activity. Of 11 PATs known from rodent malaria parasites five have been detected in blood stage parasites of P. berghei using an HA-tagging approach: they are DHHC3 (IMC), DHHC5 (ER), DHHC7 (rhoptry), DHHC8 (punctate_not_Golgi), and DHHC9 (IMC). Seven DHHC-PATs were found to be redundant for P. berghei blood stage development in a reverse genetic screen: they are DHHC 3, 5, 6, 7, 9, 10 and 11.
Three PATs are under putative translational control in the female P. berghei gametocyte: dhhc2, dhhc3 and dhhc10.

Attempts to disrupt the dhhc2 gene in P. berghei were unsuccessful (see RMgm-1350) indicating an essential role of DHCC2 for blood stage development/multiplication. Phenotype analyses of the promoter-swap mutant indicate that DHHC2 plays an important role in the development of zygotes into mature ookinetes (RMgm-1349; RMgm-1351). The promoter-swap mutant produced normal numbers of female and male gametocytes and gametes and normal fertilisation rates and production of zygotes. However zygotes failed to develop into mature ookinetes. No oocysts are formed.

Phenotype
Normal numbers of gametocytes are produced. Normal fertilisation rate and ookinete production. Ookinetes however lack crystalloids (crystalloid body; crystalloid organelle). Normal numbers of oocysts are produced. However, oocysts fail to produce sporozoites.

Additional information
dhhc10 transcripts are present in female gametocytes but protein is absent (see mutant RMgm-1472 that expresses a GFP-tagged version of DHHC10). Evidence is presented for translational repression in female gametocytes. The protein is produced after fertilisation in developing zygots/ookinetes. Evidence is presented for a location of DHHC10 in the crystalloid organelles (see also RMgm-1472, RMgm-1473, RMgm-1474).

Other mutants
See palmitoyltransferase
See DHHC10


  Disrupted: Mutant parasite with a disrupted gene
Details of the target gene
Gene Model of Rodent Parasite PBANKA_0512000
Gene Model P. falciparum ortholog PF3D7_1027900
Gene productpalmitoyltransferase DHHC10, putative
Gene product: Alternative nameDHHC10
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 parasitetgdhfr
Promoter of the selectable markerpbdhfr
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

  Transgene: Mutant parasite expressing a transgene
Type and details of transgene
Is the transgene Plasmodium derived Transgene: not Plasmodium
Transgene nameA fusion of GFP (gfp-mu3) and Luciferase Firefly (LucIAV)
Details of the genetic modification
Inducable system usedNo
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 parasitegfp (FACS)
Promoter of the selectable markereef1a
Selection (positive) procedureFACS (flowsorting)
Selection (negative) procedureNo
Additional remarks genetic modificationThe GFP-Luciferase gene (1 copy) has been inserted into the 230p locus by double cross-over integration.
Additional remarks selection procedureThis reporter mutant expressing GFP-Luciferase does not contain a drug-selectable marker. This mutant has been selected by FACS sorting after transfection based on GFP fluorescence.
Other details transgene
Promoter
Gene Model of Parasite PBANKA_1133300
Gene Model P. falciparum ortholog PF3D7_1357100
Gene productelongation factor 1-alpha
Gene product: Alternative nameeef1a
Primer information details of the primers used for amplification of the promoter sequence  Click to view information
Primer information details of the primers used for amplification of the promoter sequence  Click to hide information
Sequence Primer 1
Additional information primer 1
Sequence Primer 2
Additional information primer 2
3'-UTR
Gene Model of Parasite PBANKA_0719300
Gene productbifunctional dihydrofolate reductase-thymidylate synthase, putative
Gene product: Alternative namedhfr/ts
Primer information details of the primers used for amplification the 3'-UTR sequences  Click to view information
Primer information details of the primers used for amplification the 3'-UTR sequences  Click to hide information
Sequence Primer 1
Additional information primer 1
Sequence Primer 2
Additional information primer 2
Insertion/Replacement locus
Replacement / InsertionReplacement locus
Gene Model of Parasite PBANKA_0306000
Gene product6-cysteine protein
Gene product: Alternative name230p
Primer information details of the primers used for amplification of the target sequences  Click to view information
Primer information details of the 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