Thermal properties of red blood cells infected by malaria parasites.
Three membrane thermotropic transitions at 8, 20, and 40 degrees C have been detected in human red blood cells (RBC) by using spin-labeled stearic acids. Red blood cells infected in vitro by Plasmodium falciparum showed the disappearance of the 8 degrees C transition and a lowering of the 40 degrees C transition to 32 degrees C. The disappearance of the 8 degrees C transition was observed in synchronized cultures of P. falciparum trophozoites as well as in mouse RBC infected in vivo by an asynchronous population of P. berghei. Furthermore, erythrocytes infected by P. falciparum showed an increase in the phosphorylation of protein 4.1. This protein was shown previously to be involved in the 8 degrees C transition, (T. Forte, T. L. Leto, M. Minetti, and V. T. Marchesi, Biochemistry 24, 7876-7880 (1985). Our results suggest that the malaria parasite invasion produces a disorganization of the protein 4.1-membrane interaction.
Forte
T
T
Istituto Superiore di Sanità, Laboratorio di Biologia Cellulare, Rome, Italy.
Roca
L
L
D000818:Animals; D003598:Cytoskeletal Proteins; D004578:Electron Spin Resonance Spectroscopy; D004910:Erythrocyte Membrane / Q000502:physiology*; D004912:Erythrocytes / Q000469:parasitology* / Q000502:physiology; D006801:Humans; D066298:In Vitro Techniques; D008288:Malaria / Q000097:blood*; D008565:Membrane Proteins / Q000032:analysis / Q000097:blood / Q000302:isolation & purification; D051379:Mice; D009479:Neuropeptides; D010766:Phosphorylation; D010962:Plasmodium berghei / Q000472:pathogenicity*; D010963:Plasmodium falciparum / Q000472:pathogenicity*; D013049:Spectrin / Q000032:analysis; D013113:Spin Labels; D013696:Temperature; D013816:Thermodynamics
D003598:Cytoskeletal Proteins; D008565:Membrane Proteins; D009479:Neuropeptides; D013113:Spin Labels; C028841:erythrocyte membrane band 4.1 protein; C120557:erythrocyte membrane protein band 4.1-like 1; D013049:Spectrin