Role of the membrane interface on the conformation of the caveolin scaffolding domain: A CD and NMR study

Circular dichroism (CD) and NMR spectroscopy were used to study the conformational properties of two synthetic peptides, D82–R101 and D82–I109, encompassing the caveolin scaffolding domain (D82–R101), in the presence of dodecylphosphocholine (DPC) micelles. Our data show that a stable helical conformation of the caveolin scaffolding domain in a membrane mimicking system is only obtained for the peptide including the L102–I109 hydrophobic stretch, a part of the caveolin intra-membrane domain. Through chemical shift variations, an ensemble of six residues of the D82–L109 peptide, mainly located in the V94TKYWFYR101 motif were found to detect the presence of phosphatidylserine solubilized in DPC micelles. Our results constitute a first step for elucidating at a residue level the conformational properties of the central region of the caveolin-1 protein.