Translocation properties of novel cell penetrating transportan and penetratin analogues

Novel analogues of the cell-penetrating peptides penetratin and transportan were synthesized. The distribution of the biotin-labeled peptides in Bowes melanoma cell line has been investigated by indirect fluorescence with flu orescein-streptavidin detection. The time course of uptake of I-125-labeled transportan analogues has been characterized in the same cell line. Molecu lar modeling was used to analyze the penetration and the orientation of mol ecules in a simulated biological membrane. The results, both from molecular modeling and fluorescence studies, imply that penetratin and transportan d o not enter the cells by related mechanisms and that they do not belong to the same family of translocating peptides.