STRUCTURE AND REGULATION OF L-TYPE CALCIUM CHANNELS - A CURRENT ASSESSMENT OF THE PROPERTIES AND ROLES OF CHANNEL SUBUNITS

L-type Ca channels ave complex heteromultimeric proteins that play imp ortant roles in the cardiovascular system. Recent studies have reveale d new insights into how the pore-forming alpha(1) subunits interact wi th accessory subunits to produce functional Ca channels. The function of L-type Ca channels is often regulated by receptor-mediated signal t ransduction events that ave thought to result in the phosphorylation o f proteins that comprise the Ca channels. Although the molecular event s underlying phosphorylation based regulation have been intensely inve stigated with the use of electrophysiological approaches, surprisingly few details are known about the biochemical events involved and many questions remain unanswered. (C) 1996, Elsevier Science Inc.