title: Probing length effects and mechanism of cell penetrating agents mounted on a polyproline helix scaffold.
abstract: Cell penetrating peptides (CPP) displaying a type II polyproline helix backbone of different length and amphiphilic character were synthesized and their cellular uptake was compared. The longer CPP sequence, P14LRR, displayed a 7- to 12-fold higher uptake in MCF-7 cells as compared to its shorter counterpart, P11LRR, and a 35-fold higher uptake as compared to Tatp. These results demonstrate that an increased number of cationic and hydrophobic residues can strongly influence the extent of cellular internalization. Mechanistic investigations suggest internalization via a receptor independent endocytotic pathway with these agents.
authors.affiliation: Department of Chemistry, Purdue University, 560 Oval Drive, West Lafayette, Indiana 47907, USA.
authors.forename: Iris
authors.initials: I
authors.lastname: Geisler
authors.forename: Jean
authors.initials: J
authors.lastname: Chmielewski
mesh_terms: D004705:Endocytosis; D057927:Hydrophobic and Hydrophilic Interactions; D015336:Molecular Probe Techniques; D010455:Peptides / Q000737:chemistry* / Q000494:pharmacology; D017433:Protein Structure, Secondary; D014407:Tumor Cells, Cultured
chemical_list: D010455:Peptides; C011083:polyproline