Mutant/mutation
The mutant lacks expression of Pla1

Protein (function)
A total of 22 genes have been identified thus far, having similarities to the representative members of at least one of the four groups of known phospholipases; PLA, PLB, PLC and PLD. Out of these, 15 have the α/β hydrolase fold, four have the patatin-like phospholipase (PLP) domain and the remaining three have lecithin:cholesterol acyltransferase (LCAT), exonuclease-endonuclease-phosphatase (EEP) and DDHD domains. An interesting class of enzymes is the intracellular PLA1 family. In most eukaryotes, there is only one enzyme of this family while there are three members in mammals. Early  characterization efforts identified a phosphatidic acid (PA) preferring phospholipase A1 (PAPLA1) a putative phospholipase, DDHD1 (PbPla1, PlasmoDB accession number: PBANKA_1423100), which is the only P. berghei homolog of PA-PLA1 (Pla1)

Phenotype
Salivary gland sporozoite in vivo infectivity was checked by i.v injecting in C57BL/6 mice. Initially, 5,000 sporozoites from WT GFP or Pla1- were used, and while the appearance of blood-stage infection was observed on the third day in all mice infected with WT GFP, a delay of 2.5 – 3.5 days was observed in the appearance of Pla1- blood-stage infection. To quantify the sporozoite invasion and subsequent development in the liver, we infected mice with 5x103 sporozoites and the liver parasite burden was quantified at  40  h p.i. by measuring the parasite 18S rRNA copy number using real-time PCR. There was no significant difference in liver parasite burdens between WT GFP and Pla1-. EEFs were also counted at 40 h p.i. in multiple experiments and no difference from wild type was observed, signifying normal productive invasion and development by Pla1- sporozoites (Fig. 4C). EEF growth was also monitored by measuring their areas at 40 h and 65 h p.i., with no significant difference from WT GFP. Subsequently, maturation of EEFs and the formation of merozoites was observed by anti-MSP1 staining. Both nuclear division and merozoite formation appeared normal in Pla1-EEFs. In vitro cell detachment was quantified for Pla1- and comparatively fewer detached cells  (DCs) were detected floating in the cell culture medium even up to 70 h p.i. Evidence is presented that Pla1 has a role in merosome release.

Additional information
See mutant RMgm-5204 expressing a C-terminal 3xHA-mCherry-tagged version of Pla1 with expression in blood stages and liver stages

Other mutants