Functional nicotinic acetylcholine receptor reconstitution in Au(111)-supported Thiolipid Monolayers

DIEGO E. PISSINIS; CAROLINA DIAZ; ELIANA MAZA; IDA C. BONINI; FRANCISCO J. BARRANTES; ROBERTO C. SALVAREZZA.; PATRICIA L. SCHILARDI

Nanoscale

Royal Society Of Chemistry

Año: 2015 vol. 7 p. 15789 - 157897

2040-3364

The insertion and function of the muscle-type nicotinic acetylcholine receptor (nAChR) in Au(111)-supported thiolipid self-assembled monolayers has been studied by atomic force microscopy (AFM), surface plasmon resonance (SPR), and electrochemical techniques. It was possible for the first time to resolve the supramolecular arrangement of the protein spontaneously inserted in a thiolipid monolayer in aqueous solution. Geometric supramolecular arrays of nAChRs were observed, most commonly in a triangular form compatible with three nAChR dimers of ~20 nm each. Addition of the full agonist carbamoylcholine activated and opened the nAChR ion channel, as revealed by the increase in capacitance relative to that of the nAChR-thiolipid system under basal conditions. Thus, the self-assembled system appears to be a viable biomimetic model to measure ionic conductance mediated by ion-gated ion channels under different experimental conditions, with potential applications in biotechnology and pharmacology.