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Updated: Jun 28, 2026

Peptide-based Identification of Functional Motifs and their Binding Partners
Published on: June 30, 2013
A novel cell-penetrating peptide sequence derived by structural minimization of a snake toxin exhibits preferential
Gandhi Rádis-Baptista1, Beatriz G de la Torre, David Andreu
1Department of Experimental and Health Sciences, Pompeu Fabra UniVersity, Dr Aiguader, 80, E-08003 Barcelona, Spain.
Abstract:
Structural simplification of a 42-residue venom peptideby N-to-C-terminal splicing led to two sequences [YKQCHKKGGXKKGSG, where X = nil (1) or 6-aminohexanoyl (2)], both efficiently uptaken by HeLa cells and, most interestingly, specifically localized at the nucleolus. Retro-2 was uptaken less efficiently, but a single (His --> Ile) replacement recovered the translocation ability. None of the peptides were cytotoxic up to 100 microM. Enantio-1 did not translocate, suggesting that peptide uptake was receptor-mediated.
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