RMgmDB - Rodent Malaria genetically modified Parasites

Summary

RMgm-52

Malaria parasite	P. berghei
Genotype
Mutated	Gene model (rodent): PBANKA_1349800; Gene model (P.falciparum): PF3D7_1335900; Gene product: thrombospondin-related anonymous protein \| sporozoite surface protein 2 (sporozoite surface protein 2; SSP2; SSP-2; TRAP) Details mutation: Mutations in both the A- and TSR-domain
Phenotype	Sporozoite; Liver stage;

Last modified: 4 March 2010, 23:36

*RMgm-52

Successful modification	The parasite was generated by the genetic modification
The mutant contains the following genetic modification(s)	Gene mutation
Reference (PubMed-PMID number)	Reference 1 (PMID number) : 11927544
MR4 number
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Parent parasite used to introduce the genetic modification
Rodent Malaria Parasite	P. berghei
Parent strain/line	P. berghei NK65
Name parent line/clone	Not applicable
Other information parent line
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The mutant parasite was generated by
Name PI/Researcher	K. Matuschewski, V. Nussenzweig, R. Menard
Name Group/Department	Department of Pathology, Kaplan Cancer Center
Name Institute	New York New York University School of Medicine
City	New York
Country	USA
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Name of the mutant parasite
RMgm number	RMgm-52
Principal name	Ado/TSR
Alternative name
Standardized name
Is the mutant parasite cloned after genetic modification	Yes
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Phenotype
Asexual blood stage	Not different from wild type
Gametocyte/Gamete	Not different from wild type
Fertilization and ookinete	Not different from wild type
Oocyst	Not different from wild type
Sporozoite	Normal numbers of midgut sporozoites are formed. Strongly decreased numbers of salivary gland sporozoites (<5% of wild type)). Sporozoites show normal gliding motility. Sporozoites were not infective to rats (Sprague/Dawley). Adhesion to HepG2 cells in vitro was not affected. The sporozoites did not invade HepG2 cells in vitro.
Liver stage	Sporozoites were not infective to rats (Sprague/Dawley). Adhesion to HepG2 cells in vitro was not affected. The sporozoites did not invade HepG2 cells in vitro.
Additional remarks phenotype	Mutant/mutation The mutant expresses a mutated form of TRAP (thrombospondin-related anonymous protein). In the mutated gene a conserved threonine (Thr126) in the A-domain is replaced by alanine, aiming at disrupting the adhesive function of the A-domain and the basic residues (256KIRKRK261 cluster) in the C-terminal cluster in the TSR-domain were changed to alanine residues. Protein (function) TRAP 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). TRAP is located in the micronemes of sporozoites. The protein plays a role in the gliding motility of sporozoites and invasion of host cells as has been shown by analysis of mutant parasites lacking expression of TRAP(RMgm-47; RMgm-53). Phenotype Analysis of the phenotype of the mutant with a mutated A-domain and TSR domain show that both domains are not involved in gliding motility but play a role in entry into cells of both the salivary gland and the liver. It does not act as an adhesin. The role of the different domains of the protein in motility and invasion has been analysed in other mutant parasites expressing mutated forms of TRAP (see below). Other mutants P. berghei mutants have been generated with mutated cytoplasmic tails of TRAP (RMgm-54; RMgm-55; RMgm-56; RMgm-57; RMgm-149; RMgm-150; RMgm-151). Other P. berghei mutants have been generated with mutated extracellular (adhesive) domains (A-domain: RMgm-48; RMgm-49; TSR domain: RMgm-50; RMgm-51. A P. berghei mutant has been generated in which the endogenous P. berghei trap was replaced with (mutated forms of) P. falciparum trap (RMgm-58)

Mutated: Mutant parasite with a mutated gene

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Details of the target gene

Gene Model of Rodent Parasite

PBANKA_1349800

Gene Model P. falciparum ortholog

PF3D7_1335900

Gene product

thrombospondin-related anonymous protein | sporozoite surface protein 2

Gene product: Alternative name

sporozoite surface protein 2; SSP2; SSP-2; TRAP

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Details of the genetic modification

Short description of the mutation

Mutations in both the A- and TSR-domain

Inducable system used

Short description of the conditional mutagenesis

Not available

Additional remarks inducable system

Type of plasmid/construct

Plasmid single cross-over

PlasmoGEM (Sanger) construct/vector used

Modified PlasmoGEM construct/vector used

Plasmid/construct map

Plasmid/construct sequence

Restriction sites to linearize plasmid

Selectable marker used to select the mutant parasite

pbdhfr

Promoter of the selectable marker

pbdhfr

Selection (positive) procedure

pyrimethamine

Selection (negative) procedure

Additional remarks genetic modification

The construct used results in 'disruption of the wild type trap-gene and introduction of a full length mutated trap gene under control of the wild type regulatory (3'UTR, 5'UTR) sequences. In the mutated gene a conserved threonine (Thr126) in the A-domain is replaced by alanine, aiming at disrupting the adhesive function of the A-domain and the basic residues (256KIRKRK261 cluster) in the C-terminal cluster in the TSR-domain were changed to alanine residues.

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

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