1. Molecular interactions between Anopheles stephensi midgut cells and Plasmodium berghei: the time bomb theory of ookinete invasion of mosquitoes
- Author
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Joanne Thompson, Fotis C. Kafatos, Yeon Soo Han, and Carolina Barillas-Mury
- Subjects
Vacuolar Proton-Translocating ATPases ,Plasmodium berghei ,Models, Biological ,General Biochemistry, Genetics and Molecular Biology ,Epithelial Damage ,Anopheles ,parasitic diseases ,Botany ,medicine ,Animals ,Fragmentation (cell biology) ,Molecular Biology ,Anopheles stephensi ,Actin ,DNA Primers ,Wound Healing ,Base Sequence ,Cell Death ,Virulence ,General Immunology and Microbiology ,biology ,General Neuroscience ,Serine Endopeptidases ,fungi ,Epithelial Cells ,Midgut ,Articles ,biology.organism_classification ,Actins ,Epithelium ,Cell biology ,DNA-Binding Proteins ,Proton-Translocating ATPases ,medicine.anatomical_structure ,Cytoplasm ,Trans-Activators ,Nitric Oxide Synthase ,Digestive System - Abstract
We present a detailed analysis of the interactions between Anopheles stephensi midgut epithelial cells and Plasmodium berghei ookinetes during invasion of the mosquito by the parasite. In this mosquito, P.berghei ookinetes invade polarized columnar epithelial cells with microvilli, which do not express high levels of vesicular ATPase. The invaded cells are damaged, protrude towards the midgut lumen and suffer other characteristic changes, including induction of nitric oxide synthase (NOS) expression, a substantial loss of microvilli and genomic DNA fragmentation. Our results indicate that the parasite inflicts extensive damage leading to subsequent death of the invaded cell. Ookinetes were found to be remarkably plastic, to secrete a subtilisin‐like serine protease and the GPI‐anchored surface protein Pbs21 into the cytoplasm of invaded cells, and to be capable of extensive lateral movement between cells. The epithelial damage inflicted is repaired efficiently by an actin purse‐string‐mediated restitution mechanism, which allows the epithelium to ‘bud off’ the damaged cells without losing its integrity. A new model, the time bomb theory of ookinete invasion, is proposed and its implications are discussed.
- Published
- 2000
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