Mutant/mutation
The mutant expresses a C-terminally mCherry-tagged version of type II NADH:quinone oxidoreductase (NDH2).

Protein (function)
In Plasmodium parasites, NDH2 is one out of five mitochondrial dehydrogenases that feed electrons into the mitochondrial electron transport chain (mtETC). Typically, eukaryotes possess a multi-component rotenone-sensitive NADH:ubiquinone oxidoreductase, also termed complex I, which is located in the inner mitochondrial membrane. It catalyzes the transfer of electrons from NADH to ubiquinone (coenzyme Q, Q) leading to the reduced form, ubiquinol (QH2), and is involved in establishing the electro potential across the inner mitochondrial membrane (Δψm) by pumping hydrogen ions out of the mitochondrial matrix. Plasmodium spp., however, has a rotenone-insensitive, single subunit NADH:quinone oxidoreductase, also termed alternative complex I or NDH2. This enzyme is found in some bacteria and archea as well as in yeast and plants.
Phenotype analyses of a mutant lacking expression of NDH2 (see RMgm-630) indicate that NDH2 is not essential for asexual blood stages, gametocytes and ookinetes. NDH2 has an essential role during oocyst development and the formation of sporozoites.

Phenotype
Phenotype analyses of a mutant lacking expression of NDH2 (see RMgm-630) indicate that NDH2 is not essential for asexual blood stages, gametocytes and ookinetes. NDH2 has an essential role during oocyst development and the formation of sporozoites.

Phenotype analyses of the mutant expressing mCherry-tagged NDH2 by immuno-fluorescence using anti-mCherry antibodies showed low expression in asexual blood stages. Gametocytes displayed an intense punctuate or branched staining, indicative of abundant NDH2 protein that localizes to a cellular organelle, most likely the mitochondrion. In ookinetes, a prominent concentration of the signal in a branched structure adjacent to the parasite nucleus was detectable. NDH2 protein was prominent in oocysts and late liver stages, but absent in sporozoites. In gametocytes and ookinetes, the mCherry-signals showed overlap with signals of mitotracker, a mitochondrial-specific fluorescent dye.

Additional information

Other mutants
RMgm-630: A mutant lacking expression of NDH2 and expressing GFP under the control of the ndh2 promoter.