Temperature acclimation of Trypanosoma cruzi epimastigote and metacyclic trypomastigote lipids.

This study examines the changes in cellular lipids that take place when Trypanosoma cruzi epimastigotes and metacyclic trypomastigotes are transferred from 28 to 37 degrees C. We found a rise in the sterol to phospholipid ratio, as well as in the triacylglycerol and steryl ester cellular content in T. cruzi epimastigotes.

Diversity of roles of protein kinase C alpha in the proliferation of Swiss 3T3 cells.

We examined the role of protein kinase C alpha (PKC alpha ) in the stimulation of DNA synthesis of Swiss 3T3 cells induced by bombesin, platelet-derived growth factor (PDGF) and phorbol 12-myristate 13-acetate (PMA). We found that cells in which this kinase had been down-regulated showed a partially abrogated mitogenic response to bombesin. The response to PDGF was unaltered; however, the response to PMA was completely suppressed.

The molecular basis of the self/nonself selectivity of a coelenterate toxin.

Coelenterates produce potent hemolysins inhibited by sphingomyelin (SM). Remarkably, instead of this lipid, their membranes contain a phosphono analogue of it. Using coelenterolysin (CL), a toxin produced by the sea anemone Phymactis clematis, we have examined a possible connection between these two peculiar traits.