title: Cell penetration properties of a highly efficient mini maurocalcine Peptide.
abstract: Maurocalcine is a highly potent cell-penetrating peptide isolated from the Tunisian scorpion Maurus palmatus. Many cell-penetrating peptide analogues have been derived from the full-length maurocalcine by internal cysteine substitutions and sequence truncation. Herein we have further characterized the cell-penetrating properties of one such peptide, MCaUF1-9, whose sequence matches that of the hydrophobic face of maurocalcine. This peptide shows very favorable cell-penetration efficacy compared to Tat, penetratin or polyarginine. The peptide appears so specialized in cell penetration that it seems hard to improve by site directed mutagenesis. A comparative analysis of the efficacies of similar peptides isolated from other toxin members of the same family leads to the identification of hadrucalcin's hydrophobic face as an even better CPP. Protonation of the histidine residue at position 6 renders the cell penetration of MCaUF1-9 pH-sensitive. Greater cell penetration at acidic pH suggests that MCaUF1-9 can be used to specifically target cancer cells in vivo where tumor masses grow in more acidic environments.
authors.affiliation: Unité Inserm U836, Grenoble Institute of Neuroscience, Université Joseph Fourier, La Tronche, Chemin Fortuné Ferrini, Bâtiment Edmond Safra, 38042 Grenoble Cedex 09, France. michel.dewaard@ujf-grenoble.fr.
authors.forename: Céline
authors.initials: C
authors.lastname: Tisseyre
authors.forename: Eloi
authors.initials: E
authors.lastname: Bahembera
authors.forename: Lucie
authors.initials: L
authors.lastname: Dardevet
authors.forename: Jean-Marc
authors.initials: JM
authors.lastname: Sabatier
authors.forename: Michel
authors.initials: M
authors.lastname: Ronjat
authors.forename: Michel
authors.initials: M
authors.lastname: De Waard