Microneme
From Palaeos.org
Electron-dense, convoluted tubular organelles forming part of the apical complex in in the Apicomplexa. Micronemes are often associated with, or give rise to, the rhoptries. Also called sarconeme. Apicomplexan parasites actively secrete proteins at their apical pole as part of the host cell invasion process in response to free Ca++ in the parasite's cytoplasm. The adhesive micronemal proteins are involved in the recognition of host cell receptors. Redistribution of these receptor-ligand complexes toward the posterior pole of the parasites is powered by the actinomyosin system of the parasite and is presumed to drive parasite gliding motility and host cell penetration.
[edit] References
Carruthers, VB & LD Sibley (1999), Mobilization of intracellular calcium stimulates microneme discharge in Toxoplasma gondii. Mol. Microbiol. 31: 421–428.
Lovett, JL, N Marchesini, SNJ Moreno & LD Sibley (2002), Toxoplasma gondii microneme secretion involves intracellular Ca2+ release from inositol 1,4,5-triphosphate (IP3)/ryanodine- sensitive Stores. J. Biol. Chem. 277: 25870–25876.
Credits
ATW?
