Mutant/mutation
The mutant lacks expresses a C-terminal mCherry-tagged version of SERA4 and expresses GFP under the constitutive eef1a promoter

Protein (function)
The Plasmodium berghei PbSERA4 (PBANKA_0304800) gene encodes a cysteine-type SERA and is conserved and syntenic across the primate and rodent Plasmodium species. The predicted orthologue of PbSERA4 in Plasmodium falciparum is PfSERA7 (PF3D7_0207400), and the proteins encoded by these genes are 44% identical and 57% similar. Within the signature papain family cysteine protease domain (PFAM: PF00112), PbSERA4 and PfSERA7 share 66% amino acid identity and include the strictly conserved catalytic residues, i.e. an amino-terminal glutamine, the catalytic cysteine residue, a central histidine, and a carboxy-terminal asparagine.

Phenotype
Analyses of a mutant lacking expression of SERA4 (RMgm-4871) provided evidence that that liver-stage Pbsera4(-) parasites are released inefficiently from infected hepatocytes, but that they are infectious to red blood cells.

Analyses of the mutant expressing mCherry-tagged SERA 4 showed:
'We detected PbSERA4-mCherry signal in late asexual blood stages and gametocytes, and we could observe red fluorescence throughout exflagellation of male gametes. We failed to detect a red fluorescent signal in PbSERA4-mCherry sporozoites isolated from mosquito midguts or salivary glands despite the presence of PbSERA4 transcripts. No mCherry signal could be detected in early liver-stage P. berghei. However fluorescent protein expression in both lines is evident later in the liver stage. PbSERA4-mCherry could be detected 48 hours after infection of cultured cells with PbSERA4-mCherry sporozoites. The PbSERA4-mCherry signal progressively increased, and late liver schizonts and liver merozoites exhibited bright fluorescence'. 

Additional information

Other mutants