Phosphorylation of a P-glycoprotein homologue in Plasmodium falciparum

Abstract

A P-glycoprotein homologue has been previously identified in Plasmodium falciparum and was termed PGH 1. This paper describes studies analyzing the phosphorylation of the PGH 1 molecule. It was found, by metabolic labeling with [32P]orthophosphate, that PGH 1 was phosphorylated throughout the entire asexual erythrocytic life cycle of the parasite, with the maximum level of 32P incorporation during the trophozoite and schizont stages. Incubation of trophozoites with modulators of mammalian protein kinases suggests that a Ca2+-dependent protein kinase is involved in phosphorylation of PGH 1. PGH 1 could also be phosphorylated in the presence of γ-32P ATP on purified digestive vacuoles where th..