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Updated: Aug 23, 2026

Biotinylated Cell-penetrating Peptides to Study Intracellular Protein-protein Interactions
Published on: December 20, 2017
Calcitonin-derived carrier peptide plays a major role in the membrane localization of a peptide-cargo complex
Sylvie Boichot1, Ulrike Krauss, Thomas Plénat
1Nanostructures et Complexes Membranaires, C.B.S. CNRS UMR5048-INSERM U554, 29 rue de Navacelles, 34090 Montpellier Cedex, France.
Abstract:
Bilayers made of dioleoylphosphatidylcholine (DOPC)/dipalmitoylphosphatidylcholine (DPPC) mixture containing or not cholesterol (Chl) were used to investigate the interaction of a carrier peptide with membranes. Atomic force microscopy revealed that the C-terminal 9-32 fragment of human calcitonin (hCT (9-32)), free or coupled to enhanced green fluorescent protein (hCT-eGFP) cargo forms aggregates in the DOPC fluid phase in absence of Chl and in the DPPC enriched liquid-ordered phase when Chl is present. The data show that hCT (9-32) plays a determinant role in the membrane localization of the peptide-cargo complex. They suggest that carpet-like mechanism for membrane destabilization may be involved in the carrier function of hCT (9-32).
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