Mutant/mutation
The mutant lacks expression of nucleoside transporter 1 (NT1) and expresses GFP under the control of the Plasmodium berghei hsp70 promoter.

Protein (function)
Plasmodium lacks the enzymatic machinery necessary for the synthesis of the purine ring de novo and rely solely on the uptake of host purines for DNA synthesis. For P. falciparum it has been demonstrated that the translocation of host purines into the parasite is mainly mediated by the plasma membrane permease PfNT1 (nucleotide transporter 1). Genetic studies demonstrated that PfNT1 plays an essential role in parasite development and replication within human erythrocytes and parasites lacking PfNT1 are conditionally lethal, growing only when purines are provided at supra-physiological concentrations (El Bissati et al., 2006, PNAS 103, 9286-91; El Bissati, 2008, Mol. Biochem. Parasitol. 161, 130-9).

Phenotype
Reduced growth and multiplication of asexual blood stage parasites. Parasites do not induce experimental cerebral complications in C57BL/6 mice and mice can resolve infections.

Additional information
See also RMgm-387 for a P. yoelii mutant lacking expression of NT1. Asexual blood stages of this mutant also show a strongly reduced growth and multiplication. Cloning of the P. yoelii mutant by limiting dilution was not possible (see 'Additional information').

Other mutants
RMgm-387: a P. yoelii mutant lacking expression of NT1