Single plasma membrane K+ channel detection by using dual-color quantum dot labeling.
K+ channels are widely expressed in eukaryotic and prokaryotic cells, where one of their key functions is to set the membrane potential. Many K+ channels are tetramers that share common architectural properties. The crystal structure of bacterial and mammalian K+ channels has been resolved and provides the basis for modeling their three-dimensional structure in different functional states. This wealth of information on K+ channel structure contrasts with the difficulties to visualize single K+ channel proteins in their physiological environment. We describe a method to identify single Ca2+-activated K+ channel molecules in the plasma membrane of migrating cells. Our method is based on dual-color labeling with quantum dots. We show that >90% of the observed quantum dots correspond to single K+ channel proteins. We anticipate that our method can be adopted to label any other ion channel in the plasma membrane on the single molecule level.
Nechyporuk-Zloy
Volodymyr
V
Institute of Physiology II, Univ. of Münster, Robert-Koch-Strasse 27b, D-48149 Münster, Germany.
Stock
Christian
C
Schillers
Hermann
H
Oberleithner
Hans
H
Schwab
Albrecht
A
D000818:Animals; D002460:Cell Line; D002462:Cell Membrane / Q000378:metabolism* / Q000648:ultrastructure*; D004285:Dogs; D007668:Kidney / Q000378:metabolism* / Q000648:ultrastructure*; D008832:Microchemistry / Q000379:methods; D036641:Microscopy, Fluorescence, Multiphoton / Q000379:methods*; D024681:Potassium Channels, Calcium-Activated / Q000378:metabolism* / Q000648:ultrastructure*; D045663:Quantum Dots; D013194:Staining and Labeling / Q000379:methods
D024681:Potassium Channels, Calcium-Activated