Microneme Proteins in Apicomplexans

  • Vern B. CarruthersEmail author
  • Fiona M. Tomley
Part of the Subcellular Biochemistry book series (SCBI, volume 47)


The invasive stages (zoites) of most apicomplexan parasites are polarised cells that use their actinomyosin-powered gliding motility or “glideosome” system to move over surfaces, migrate through biological barriers and invade and leave host cells. Central to these processes is the timely engagement and disengagement of specific receptors upon the regulated release of apical invasion proteins from parasite secretory organelles (micronemes, rhoptries). In this short review, we summarise recent progress on identification and functional characterisation of apical invasion proteins mobilised to the parasite surface from the microneme organelles. We have restricted our focus to Toxoplasma, Eimeria, Cryptosporidium and the nonerythrocytic stages of Plasmodium because these organisms have been the most intensively studied apicomplexans that invade nucleated cells and because invasion by erythrocytic stages of Plasmodium is covered in the next chapter.


Toxoplasma Gondii Apical Membrane Antigen Apicomplexan Parasite Parasite Invasion Host Cell Surface 
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© Landes Bioscience and Springer Science+Business Media 2008

Authors and Affiliations

  1. 1.Department of Microbiology and ImmunologyUniversity of Michigan School of MedicineAnn ArborUSA
  2. 2.Division of MicrobiologyInstitute for Animal HealthBerkshireUK

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