Mutant/mutation
The mutant lacks expression of CTRP ( and expresses a C-terminal mCherry tagged P28 protein.

The ctrp gene was disrupted in mutant RMgm-4071 that expresses a C-terminal mCherry tagged P28 protein.

Both for tagging P28 and for disruption of CTRP the CRISPR/Cas9 method was used as described for mutant RMgm-1095  with a slight modification of the pYCm vector. In this vector the original hdhfr slectable marker was replaced by the hdhfr-yfcu selectable marker. This allows for killing mutated parasites that still contain remaining episomal plasmids by 5-FC treatment of mice. Removal of the episomal plasmid is essential for subsequent mutations in the same parasite using the CRISPR/Cas9 method.

Protein (function)
CTRP 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). CTRP has six tandemly arrayed A domains followed by seven TSP type 1-like domains. CTRP is located in the micronemes of ookinetes. This structure is similar to that of TRAP (PF13_0201; PB000374.03.0), a malaria sporozoite protein critical for sporozoite motility and invasion into host cells.
CTRP plays a role in the motility of ookinetes and invasion of midgut epithelial cells.

Phenotype
Ookinetes show reduced motility (complete defect in forward gliding motility). No oocyst are formed.

Additional information
See mutant RMgm-1095 for a detailed description of the CRISPR/Cas9 method.
Both for tagging P28 and for disruption of CTRP the CRISPR/Cas9 method was used as described for mutant RMgm-1095  with a slight modification of the pYCm vector. In this vector the original hdhfr slectable marker was replaced by the hdhfr-yfcu selectable marker. This allows for killing mutated parasites that still contain remaining episomal plasmids by 5-FC treatment of mice. Removal of the episomal plasmid is essential for subsequent mutations in the same parasite using the CRISPR/Cas9 method.

Other mutants