Functional dissection of the apicomplexan glideosome molecular architecture.
The glideosome of apicomplexan parasites is an actin- and myosin-based machine located at the pellicle, between the plasma membrane (PM) and inner membrane complex (IMC), that powers parasite motility, migration, and host cell invasion and egress. It is composed of myosin A, its light chain MLC1, and two gliding-associated proteins, GAP50 and GAP45. We identify GAP40, a polytopic protein of the IMC, as an additional glideosome component and show that GAP45 is anchored to the PM and IMC via its N- and C-terminal extremities, respectively. While the C-terminal region of GAP45 recruits MLC1-MyoA to the IMC, the N-terminal acylation and coiled-coil domain preserve pellicle integrity during invasion. GAP45 is essential for gliding, invasion, and egress. The orthologous Plasmodium falciparum GAP45 can fulfill this dual function, as shown by transgenera complementation, whereas the coccidian GAP45 homolog (designated here as) GAP70 specifically recruits the glideosome to the apical cap of the parasite.
Department of Microbiology and Molecular Medicine, Centre Medical Universitaire, University of Geneva, CH-1211 Geneva 4, Switzerland.
Karine
K
Frénal
Valérie
V
Polonais
Jean-Baptiste
JB
Marq
Rolf
R
Stratmann
Julien
J
Limenitakis
Dominique
D
Soldati-Favre
D000199:Actins / Q000378:metabolism; D000215:Acylation; D000595:Amino Acid Sequence; D002462:Cell Membrane / Q000378:metabolism; D002478:Cells, Cultured; D017124:Conserved Sequence; D005816:Genetic Complementation Test; D006790:Host-Parasite Interactions; D006801:Humans; D008565:Membrane Proteins / Q000378:metabolism*; D008969:Molecular Sequence Data; D018994:Myosin Light Chains / Q000378:metabolism*; D010963:Plasmodium falciparum / Q000378:metabolism*; D015800:Protozoan Proteins / Q000378:metabolism*; D014122:Toxoplasma / Q000378:metabolism*; D014162:Transfection
D000199:Actins; D008565:Membrane Proteins; D018994:Myosin Light Chains; D015800:Protozoan Proteins; C509918:glideosome-associated protein 45, Plasmodium falciparum