Apoptosis in procyclic Trypanosoma brucei rhodesiense in vitro

Apoptosis is a phenomenon previously associated exclusively with metazoan organisms. We show here that procyclic insect form Trypanosoma brucei rhodesiense, a protozoan parasite, when treated in vitro with concanavalin A displayed several features normally associated with apoptosis in metazoan cells. Lectin treatment induced cleavage of nuclear DNA into oligonucleosomal fragments, suggesting activation of an endogenous nuclease in the parasite. Treated trypanosomes, although agglutinated and non-motile, exhibited fluorescence after treatment with the vital stain fluorescein diacetate and retained (3)H-uridine indicating that their cell membranes remained intact during the period of DNA fragmentation. Electron micrographs showed characteristic morphology of cells undergoing apoptosis, including surface membrane vesiculation and migration of chromatin to the periphery of the nuclear membrane while mitochondria remained intact. These results suggest that treatment with concanavalin A triggers a cell death mechanism in T. b. rhodesiense similar to the process of apoptosis described in metazoa.     

European checkerspots (Melitaeini: Lepidoptera,Nymphalidae) are not aposematic – the point of view of great tits (Parus major)

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Dynamic changes in the microbial community composition in microbial fuel cells fed with sucrose

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ONTOGENETIC NICHE SHIFT IN THE BRACHIOPOD TEREBRATALIA TRANSVERSA: RELATIONSHIP BETWEEN THE LOSS OF ROTATION ABILITY AND ALLOMETRIC GROWTH

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Specificity of Lysine:N-Hydroxylase: A Hypothesis for a Reactive Substrate Intermediate in the Catalytic Mechanism

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Stimulation of in vivo tumor growth and phorbol ester-induced inflammation by N,N-diethyl-2-[4-(phenylmethyl)phenoxy] ethanamine HCl, a potent ligand for intracellular histamine receptors

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