Skip to Main content Skip to Navigation
Journal articles

Cryofracture Electron Microscopy of the Ookinete Pellicle of Plasmodium gallinaceum Reveals the Existence of Novel Pores in the Alveolar Membranes

Abstract : The malaria parasite invades the midgut tissue of its mosquito host as a motile form called the ookinete. We have examined the pellicle of the ookinete of Plasmodium gallinaceum by freeze-fracture and quick-freeze, deep-etch electron microscopy. The general organization is analogous to that of invasive stages of other members of Apicomplexa. The pellicle is composed of three membranes: the plasma membrane, and the two linked intermediate and inner membranes, which in the ookinete form one flattened vacuole that is located beneath the plasma membrane. The edges of this vacuole form a longitudinal suture. Beneath the vacuole is found an array of microtubules that are connected to the inner membrane by intramembranous particles. During freeze-fracture, the membranes can split along their hydrophobic planes, thus yielding six fracture faces, each of which displays a characteristic pattern of intramembranous particles. Additionally, we find that the ookinete pellicle differs from all other apicomplexan motile stages by the presence of large pores. These pores are of unknown function, but clearly might constitute a novel pathway for the transport of molecules to and from the cortex, which is independent of the well-described route through the apical micronemal/rhoptry complex. The pores may be the route by which motor proteins or other non micronemal surface proteins are trafficked, such as P25/P28 and SOAP, some of which are implicated in transmission blocking immunity.
Document type :
Journal articles
Complete list of metadata

https://hal-pasteur.archives-ouvertes.fr/pasteur-03661338
Contributor : Richard Paul Connect in order to contact the contributor
Submitted on : Friday, May 6, 2022 - 5:25:06 PM
Last modification on : Thursday, May 12, 2022 - 5:22:48 PM

Identifiers

Collections

Citation

Anna Raibaud, Pietro Lupetti, Richard E. Paul, David Mercati, Paul T Brey, et al.. Cryofracture Electron Microscopy of the Ookinete Pellicle of Plasmodium gallinaceum Reveals the Existence of Novel Pores in the Alveolar Membranes. Journal of Structural Biology, Elsevier, 2001, 135 (1), pp.47-57. ⟨10.1006/jsbi.2001.4396⟩. ⟨pasteur-03661338⟩

Share

Metrics

Record views

8