Membrane Effects on Ion Channel Function

Science's STKE  13 Apr 2004:
Vol. 2004, Issue 228, pp. tw136-TW136
DOI: 10.1126/stke.2282004TW136

What is the effect of the membrane environment on ion channel function? Are ion channel subunits solely responsible for channel properties, or can lipids alter the gating of potassium channels? Oliver et al. (see the Perspective by Hilgemann) demonstrate that membrane lipids can convert A-type potassium channels into delayed rectifiers, and vice versa. Phosphoinositides such as PIP2 immobilize the inactivation domain and thus remove N-type inactivation from A-type potassium channels. Conversely, the fatty acids arachidonic acid and anandamide equip delayed-rectifier channels with rapid voltage-dependent inactivation.

D. Oliver, C.-C. Lien, M. Soom, T. Baukrowitz, P. Jonas, B. Fakler, Functional conversion between A-type and delayed rectifier K+ channels by membrane lipids. Science 304, 265-270 (2004). [Abstract] [Full Text]

D. W. Hilgemann, Oily barbarians breach ion channel gates. Science 304, 223-224 (2004). [Summary] [Full Text]