Mutant/mutation
The mutant expresses a mCherry-tagged version of HSP20 (small heat shock protein, HSP20).

Protein
Plasmodium HSP20 was identified by homology searches using the Toxoplasma gondii HSP20 sequence (gi: 78368731) as query. Plasmodium HSP20 contains a central α-crystallin domain (Pfam: PF00011).

Phenotype analyses of mutants lacking expression of HSP20 (RMgm-672, RMgm-675) provide evidence that HSP20 is involved in ookinete and sporozoite motility.

Phenotype
Through analysis of expression of mCherry-tagged HSP20 and using a polyclonal antiserum against HSP20 it is shown that HSP70 is abundantly expressed in ookinetes, oocysts and sporozoites (and no or very low expression in blood stages and maturing liver stages). In addition evidence is presented that HSP20 redistributes to the apical tip in motile sporozoites. In gliding sporozoites, tagged HSP20 localizes to the plasma membrane of gliding sporozoites and accumulates at the ventral side of the anterior tip and at the posterior half. The observations in addition with immuno-electron-microscopy observations suggest that HSP20 is recruited to the cortical side of the pellicle in gliding sporozoites and that this polarization of HSP20 is a molecular signature of mature, motile, and infectious sporozoites.

Additional information
Analyis of the expression of HSP20 in infected hepatoma cells with a polyclonal antiserum showed that at 4 h after hepatocyte invasion, the HSP20 signal, likely derived from the infecting sporozoite, is still clearly detectable. This signal is progressively lost from later stage parasites, being no longer detectable in mature liver stages.

Other mutants
RMgm-675, RMgm-672:  Mutants lacking expression of HSP20 (and expressing GFP).