9.B.215 The Plasmodium Basal Complex Transmembrane Protein (BTP) Family
The intraerythrocytic developmental cycle of Plasmodium falciparum is completed with the release of up to 32 invasive daughter cells, the merozoites, into the blood stream. Before release, the final step of merozoite development is the assembly of the cortical pellicle, a multi-layered membrane structure. This unique apicomplexan feature includes the inner membrane complex (IMC) and the parasite's plasma membrane. A dynamic ring structure, referred to as the basal complex, is part of the IMC and helps to divide organelles and abscises in the maturing daughter cells. Kono et al. 2016 analyzed the dynamics of the basal complex of P. falciparum. They identified a novel transmembrane protein of the basal complex termed BTP1, which is probably specific to the genus Plasmodium. It colocalizes with the known basal complex marker protein MORN1 and shows distinct dynamics as well as localization when compared to other IMC proteins during schizogony. Using a parasite plasma membrane marker cell line, Kono et al. 2016 correlated dynamics of the basal complex with the acquisition of the maternal membrane. The found that the plasma membrane invagination and IMC propagation are interlinked during the final steps of cell division. A transport function for BTP1 has been suggested.
References:
BTP1 of 650 aas with 4 C-terminal TMSs. The N- and C-termini may be cytoplasmic (Kono et al. 2016). May be involved in pellicle formation.
BTP1 of Plasmodium falciparum
Integral membrane protein of 363 aas and 3 or 4 TMSs.
IMP of Theileria annulata
Uncharacterized membrane protein of 583 aas and 3 or 4 TMSs.
UP of Babesia bigemina
Uncharacterized protein of 158 aas and 4 TMSs.
UP of Cryptosporidium andersoni
Uncharacterized protein of 213 aas and 3 or 4 TMSs.
UP of Vitrella brassicaformis
Uncharacterized transmembrane protein of 604 aas with one N-terminal TMS and 4 C-terminal TMSs.
UP of Toxoplasma gondii
Uncharacterized protein of 414 aas and 4 TMSs
UP of Eimeria brunetti
Uncharacterized protein of 514 aas and 4 TMSs.
UP of Neospora caninum