The molecular basis for the essential role of cholesterol in mammalian (and other
cholesterol-requiring) cells has long been the object of intense interest. Cholesterol has
been found to modulate the function of membrane proteins critical to cellular function.
Current literature supports two mechanisms for this modulation. In one mechanism, the
requirement of 'free volume'by integral membrane proteins for conformational changes as
part of their functional cycle is antagonized by the presence of high levels of cholesterol in …