State of the Art in the Studies on Crotamine, a Cell Penetrating Peptide from South American Rattlesnake

Figure 2

Crotamine action in normal (red) and cancer (blue) cells. Crotamine is a positively charged (blue) protein. In normal cells, crotamine uptake occurs through clatrin-dependent endocytosis followed by lysosome accumulation, followed by its release in the cytosol due to the disruption of the vesicles containing crotamine. In normal cells, crotamine interacts electrostatically with centrioles and chromosomes and can be used as a biotechnological tool, as carrier of bioactive molecules, and as a marker of cell cycle. Cancer cells, which have more negatively charged molecules on their surface compared to normal cells, potentially attract crotamine strongly. In cancer cells, crotamine intracellular concentration appears to be higher than that observed in normal cells, thus probably leading to cell lyses and cell death. In cancer cells, crotamine inhibits tumor growth and kills tumor cells, besides representing a potential tool for in vivo cancer cells identification.