Mutant/mutation
The mutant lacks expression of AQP (aquaglyceroporin) and expresses GFP under the control of the constitutive and strong hsp70 promoter. The construct to delete the aqp gene contains a GFP expression cassette. In this cassette the gfp gene is under the control of the hsp70 promoter (see for more information on the basic plasmid pBAT-SIL6 the mutant RMgm-757)
The mutant parasite is cloned by FACS sorting (and not by limiting dilution) based on GFP expression.

Protein (function)
Aquaporins constitute a family of cellular water and solute channels. They are functionally divided into two groups, the aquaporins, which are water-specific channels, and aquaglyceroporins, which are highly permeated by glycerol and other solutes and variably permeated by water. Aquaglyceroporins are the only glycerol channels identified in mammals.

Phylogenetic analysis, in comparison with representative AQPs of human and Arabidopsis thaliana, revealed a strong association of Plasmodium AQP (PBANKA_091560; PF3D7_1132800) with human type II aquaporins and, more distantly, with the A. thaliana nodulin-like intrinsic protein  (NIP) family. Toxoplasma gondii AQP1 (TGME49_015450) clusters with the second, unusually long, predicted Plasmodium AQP (PBANKA_142710; PF3D7_0810400) and associates more closely to a clade containing the A. thaliana small basic intrinsic protein (SIP) family members and humanAQP11 and 12. Aquaporins are characterized by two ‘‘NPA’’ boxes that are relatively well conserved across most subfamilies. Sequence alignments of these motifs of P. berghei and P. falciparum AQP1 with selected aquaporin sequences, i.e. human AQP3, 7, 9, and 10 and the A. thaliana NIP subfamily members, reveals significant conservation but also some striking differences. PbAQP1 and PfAQP1 are both marked by unusual variations in the invariant ‘‘NPA’’ sequences. Furthermore, a highly conserved proline in the second ‘‘NPA’’ box is absent in both malaria parasites.

Phenotype
Phenotype analyses during blood, mosquito and liver stage parasites indicate that AQP is not essential during the complete life cycle and no phenotype was detected that was different from wild type parasites. See also mutant RMgm-265 which is an independent P. berghei mutant lacking expression of AQP. Blood stages of this mutant showed a slightly reduced growth rate.

Additional information
See also mutant RMgm-790 that expresses a C-terminal mCherry/cmyc-tagged version of AQP. mCherry-tagged AQP was found to be localized in the cytoplasm of blood stages (asexual stages and gametocytes)

See also mutant RMgm-265. Analysis of localisation of AQP using antibodies indicated a location at the plasmamembrane of blood stages

Other mutants
RMgm-265 - An independent mutant lacking expression of AQP
RMgm-790 - A mutant expressing a C-terminal mCherry/cmyc-tagged version of AQP.