INCORPORATION OF RECONSTITUTED ACETYLCHOLINE-RECEPTORS FROM TORPEDO INTO THE XENOPUS OOCYTE MEMBRANE

Xenopus oocytes are a valuable aid for studying the molecular structur e and function of ionic channels and neurotransmitter receptors. Their use has recently been extended by the demonstration that oocytes can incorporate foreign membranes carrying preassembled receptors and chan nels. Here we show that when reconstituted in an artificial lipid matr ix and injected into Xenopus oocytes, purified nicotinic acetylcholine receptors are efficiently inserted into the plasma membrane, where th ey form ''clusters'' of receptors that retain their native properties. This constitutes an innovative approach that, besides allowing the an alyses of membrane fusion processes, is also a powerful technique for studying the characteristics and regulation of many membrane proteins (with their native stoithiometry and configuration) upon reinsertion i nto the membrane of a very convenient host cell system.