An 88‐kDa protein of Plastmidium falciparum is related to the band‐3‐binding domain of human erythrocyte ankyrin

Abstract

Three typtic‐peptide sequences of an 88‐kDa pair of phosphoproteins of the malaria parasite Plasmodium falciparum were determined. They exhibit a striking similarity to corresponding sequences of the 89‐kDa domain of human erythrocyte ankyrin. [35S]Methionine labeling of the two proteins demonstrated thier parasitic origin. Using an appropriate oligonucletide probe, Southern‐blot analysis of genomic malaria DNA and Norhtern‐blot analysis of malaria RNA suggest the existence of ankyrin‐related sequences in the parasite genome and the presence of an ankyrin‐related transcirpt of about 3.2 kb. Our studies provide further evidence of malaria‐specific analogues of host‐cell proteins, implying an unusual kind of parasite/host interaction.

Export of Plasmodium falciparum calcium‐dependent protein kinase 1 to the parasitophorous vacuole is dependent on three N‐terminal membrane anchor motifs

“…[9,10( n )‐ 3 H]myristic acid (10–60 Ci mmol −1 ; New England Nuclear) in ethanol was allowed to dry on a tissue culture plate surface in quantities that brings the concentration of the isotope to 200 µCi ml −1 after addition of 5 ml of parasite culture (10% haematocrit). Labelling was performed at 37°C for 4 h. Labelled parasites were isolated by saponin lysis as described by Suetterlin et al . (1992).…”

“…[9,10(n)-3 H]myristic acid (10-60 Ci mmol -1 ; New England Nuclear) in ethanol was allowed to dry on a tissue culture plate surface in quantities that brings the concentration of the isotope to 200 mCi ml -1 after addition of 5 ml of parasite culture (10% haematocrit). Labelling was performed at 37∞C for 4 h. Labelled parasites were isolated by saponin lysis as described by Suetterlin et al (1992). The parasites were then lysed in an appropriate volume of RIPA buffer [50 mM Tris-HCl pH 8, 150 mM NaCl, 0.5% sodium deoxycholate, 50 mM NaF, 0.1% SDS, 1% Triton X-100, 5 mM EDTA supplemented with freshly added DTT (1 mM), PMSF (phenylmethylsulphonyl fluoride; 1 mM), pepstatin A (1 mg ml -1 ) and leupeptin (1 mg ml -1 )].…”

Hundreds of ankyrin‐like repeats in functionally diverse proteins: Mobile modules that cross phyla horizontally?

“…Mad.3-Human-(; Feml-(:aeei-c: a long divergent evolution of both proteins. 45 Given the similarity between human and mouse ankyrin (97% , Table II), the different ankyrin variants in mammals, and assuming correct data, an acquisition of erythrocyte ankyrin by the protozoon Plasmodium falciparum is very likely.…”

Cytoskeleton of Apicomplexan Parasites

“…It has been postulated that ROPE may be involved in invasion, by interacting with the erythrocyte cytoskeleton via molecular mimicry of spectrin. P. falciparum expresses an 88-kDa phosphoprotein that is nearly identical to the amino-terminal region of ankyrin, a region of the protein that binds band 3 (170). This protein may also help the parasite reorganize the membrane skeleton via molecular mimicry.…”