Fig. (5).

A schematic description for the efficacy enhancement of certain plant type I RIPs using triterpenoidal saponins. 1. The toxin reaches the cell 2. Internalization and formation of endosomal vesicles, 3. Maturation of the endosomal vesicles along with the entrapped toxin, 4. Late endosome formation. 5. The toxin undergoes lysosomal degradation and thus the toxic effect is not elicited. 6. Particular saponins accumulates inside the endo/lysosomes by unknown mechanisms. The presence of saponins faciliates the endo/lysosomal release of the toxin in a pH dependent manner. 7. The toxin induces cell death inside the cytosol via apoptosis.