Summary

RMgm-892
Malaria parasiteP. berghei
Genotype
DisruptedGene model (rodent): PBANKA_0932100; Gene model (P.falciparum): PF3D7_1115900; Gene product: palmitoyltransferase DHHC9 (DHHC9)
PhenotypeNo phenotype has been described
Last modified: 22 April 2016, 18:19
  *RMgm-892
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) : 23638681
Reference 2 (PMID number) : 27084458
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/ResearcherK. Frénal, J.Rayner, O. Billker, E. Bushell, D. Soldati-Favre
Name Group/DepartmentMalaria Programme
Name InstituteWellcome Trust Sanger Insitute
CityCambridge Hinxton
CountryUK
Name of the mutant parasite
RMgm numberRMgm-892
Principal namePbDHHC9 _KO
Alternative name
Standardized name
Is the mutant parasite cloned after genetic modificationYes
Phenotype
Asexual blood stageNot different from wild type
Gametocyte/GameteNot tested
Fertilization and ookineteNot different from wild type
OocystNot different from wild type
SporozoiteNot different from wild type
Liver stageNot different from wild type
Additional remarks phenotype

Mutant/mutation/phenotype

Reference PMID 23638681
This protein was selected in a study aimed at determining the repertoire of  DHHC-CRD S-acyl transferase protein family as putative candidates for protein S-acyl transferases (PATs). The genes encoding these proteins were targeted for deletion to analyse their essentiality for blood stages In addition, mutants were generated that express a HA-tagged version of the protein to identify its cellular location

The generation of parasites with a disrupted gene indicate a non-essential role during asexual blood stage growth/multiplication The gene deletion mutant has not been cloned and the phenotype of the gene deletion mutant has not been not analysed in detail (the growth rate has not been determined).

Reference PMID 27084458
In this study the mutant have been cloned and analysed in more detail during mosquito and liver stage development. No phenotype was detected in oocyst and sporozoite production, gliding motility of ookinetes and sporozoites and sporozoite infectivity.

In the same paper a double knock-out mutant is described lacking both DHHC3 (PBANKA_0927300) and DHHC9. This mutant shows a stronger reduction in oocyst and sporozoite production compared to the single DHHC3-ko parasites (RMgm-888). In addition, ookinete development was affected (aberrant, shorter ookintes) with less than 1% normal mature ookinetes).

Background:
Protein palmitoylation in particular is  a fundamental, dynamic, and widespread posttranslational mechanism that controls transport, properties and activity of proteins across eukaryotes. Unlike other irreversible lipid modifications such as myristoylation and prenylation, the addition of a 16-carbon saturated palmitate group to the sulfhydryl group of a cysteine to form a hydroxylamine-sensitive thioester linkage, is a reversible modification. This constitutes a fast and dynamic mechanism to spatiotemporally control protein function by impacting reversibly on protein trafficking, stability and clustering. While palmitoylation frequently facilitates membrane association of a soluble protein by the addition of a hydrophobic anchor, this modification also occurs on transmembrane proteins, involving other effects such as structural conformation changes, protein-protein interactions or the clustering to specific lipid domains leading, for example, to assembly of signalling complexes.
Palmitoylation can control the affinity of a protein for lipid membranes, which allows it to impact protein trafficking, stability, folding, signalling and interactions. The publication of the palmitome of the schizont stage of P. falciparum implicated a role for palmitoylation in host cell invasion, protein export and organelle biogenesis.

The enzymes mediating transfer of palmitate from palmitoyl-CoA to a protein substrate were first identified in Saccharomyces cerevisiae and subsequently in mammals. Protein S-acyl transferases (PATs) belong to the DHHC family of proteins that exhibit a catalytic Asp-His-His-Cys conserved motif located within a cysteine-rich domain (CRD) and frequently between two transmembrane regions, facing the cytosol. Substrate recognition and catalysis occur after the protein substrates have associated with membrane via another lipidation.

Other mutants
See the link DHHC for a number of other related mutants


  Disrupted: Mutant parasite with a disrupted gene
Details of the target gene
Gene Model of Rodent Parasite PBANKA_0932100
Gene Model P. falciparum ortholog PF3D7_1115900
Gene productpalmitoyltransferase DHHC9
Gene product: Alternative nameDHHC9
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-121226
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 parasitehdhfr/yfcu
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