SUBUNIT IDENTIFICATION AND RECONSTITUTION OF THE N-TYPE CA2+ CHANNEL COMPLEX PURIFIED FROM BRAIN

Calcium channels play an important role in regulating various neuronal processes, including synaptic transmission and cellular plasticity. T he N-type calcium channels, which are sensitive to omega-conotoxin, ar e involved in the control of transmitter release from neurons. A funct ional N-type calcium channel complex was purified from rabbit brain. T he channel consists of a 230-kilodalton subunit (alpha1B) that is tigh tly associated with a 160-kilodalton subunit (alpha2delta), a 57-kilod alton subunit (beta3), and a 95-kilodalton glycoprotein subunit. The c omplex formed a functional calcium channel with the same pharmacologic al properties and conductance as those of the native omega-conotoxin-s ensitive calcium channel in neurons.