Mutant/mutation
The mutant c01::gfp lacks expresses a C-terminal GFP-tagged version of PIMMS01

Protein (function)
PfPIMMS01 encodes a 163 amino acid-long protein (19 kDa) with a predicted signal peptide (aa 1–27). Its P. berghei orthologue, PbPIMMS01, encodes a much shorter 85 amino acid-long protein (9 kDa) and also contains a predicted signal peptide (aa 1–26). This suggests that both proteins are putatively secreted. While the central part of the deduced protein is highly conserved between all PIMMS01 orthologues, all rodent PIMMS01 proteins are shorter than their orthologues in human parasites, lacking the entire second half of the protein. InterPro domain analysis revealed no recognizable domain, and BLAST searches showed that the protein is Plasmodium specific.  

Phenotype
Severely reduced sporozoite numbers, suggesting that insertion of GFP compromises the function of the  protein. Also HA-tagging resulted in reduced oocyst and sporozoite numbers.
See RMgm-4997 for a mutant lacking expression of PIMMS01, showing reduced oocyst and sporozoite formation

Additional information
Three genes were selected for analysis that exhibit highly abundant transcripts 24 h post blood feeding in the midguts of Anopheles coluzzii mosquitoes.
 
PIMMS01: PF3D7_0112100; PBANKA_0201700 
PIMMS57: PF3D7_1244500; PBANKA_1457700
PIMMS22: PF3D7_0814600; PBANKA_1422900 
((PIMMS: Plasmodium Infection of the Mosquito Midgut Screen)

PbPIMMS01 and PbPIMMS57 transcripts were highly abundant in purified mature ookinetes and not detectable in mixed blood stages and purified gametocytes. While PbPIMMS57 appears to be specific for ookinetes, low levels of PbPIMMS01 transcripts are also detected in mature oocysts and midgut sporozoites at 10 days and 15 days post blood-feeding. Like PfPIMMS22, expression of PbPIMMS22 starts in gametocytes and continues at high levels at 24 hour and peaks in midgut sporozoites at day 15.

Western blot analysis using an a-GFP antibody on the nonfunctional c01::gfp line confirmed high levels of PbPIMMS01::GFP fusion protein at the expected molecular weight. The protein was found to be highly expressed in mature ookinetes of the c01::gfp line and be absent from blood stages or gametocytes or any stage of the ANKA 2.34 background. Similarly, western blot analysis on the c01::3xha transgenic line using an a-HA antibody confirmed expression of the PbPIMMS01::3xHA fusion protein in the ookinete at the expected molecular weights and absence from gametocytes. The protein was only detected in the Triton X100 soluble fraction suggesting that it is not membrane associated. Despite the strong evidence that the PbPIMMS01 GFP- and HA-tagged proteins are non-functional, these are still likely to be localised incorrectly. IFAs on the developmentally compromised c01::gfp and c01::3xha transgenic lines revealed strong cytoplasmic localization of both PbPIMMS01::GFP and PbPIMMS01::3xHA, which indicates that the protein may be stuck in a secretory pathway and suggests that the native polypeptide may be associated with the ookinete outer membrane especially during invasion. Peptide antibodies raised against P. berghei PIMMS01 did not work in western blots and IFAs.

From the abstract:
PIMMS01 and PIMMS57 are specifically and highly expressed in ookinetes, while PIMMS22 transcription starts already in gametocytes and peaks in sporozoites. All three genes show strong phenotypes associated with the ookinete to oocyst transition, as their disruption leads to very low numbers of oocysts and complete abolishment of transmission. PIMMS22 has a secondary essential function in the oocyst. 

Other mutants