Note to users. If you're seeing this message, it means that your browser cannot find this page's style/presentation instructions -- or possibly that you are using a browser that does not support current Web standards. Find out more about why this message is appearing, and what you can do to make your experience of our site the best it can be.

Subscribe

Logo for

J Appl Physiol 89 (2): 731-741

Copyright © 2000 by the American Physiological Society.

Vol. 89, Issue 2, 731-741, August 2000

In situ localization of cholesterol in skeletal muscle by use of a monoclonal antibody

Mark S. F. Clarke1,4, Charles R. Vanderburg2, Marcas M. Bamman3, Robert W. Caldwell4, and Daniel L. Feeback5

1 Division of Space Life Sciences, Universities Space Research Association, and 5 Life Sciences Research Laboratories, National Aeronautics and Space Administration/Johnson Space Center, Houston, Texas 77058; 2 Research Space Management Group, Massachusetts General Hospital, Boston, Massachusetts 02114; 3 Division of Exercise Physiology, University of Alabama at Birmingham, Birmingham, Alabama 35294; and 4 Department of Pharmacology and Toxicology, Medical College of Georgia, Augusta, Georgia 30912

A common perception is that cholesterol, the major structural lipid found in mammalian membranes, is localized nearly exclusively to the plasma membrane of living cells and that it is found in much smaller quantities in internal membranes. This perception is based almost exclusively on cell fractionation studies, in which density gradient centrifugation is used for purification of discrete subcellular membrane fractions. Here we describe a monoclonal antibody, MAb 2C5-6, previously reported to detect purified cholesterol in synthetic membranes (Swartz GM Jr, Gentry MK, Amende LM, Blanchette-Mackie EJ, and Alving CR. Proc Natl Acad Sci USA 85: 1902-1906, 1988), that is capable of detecting cholesterol in situ in the membranes of skeletal muscle sections. Localization of cholesterol, the dihydropyridine receptor of the T tubule, and the Ca2+-ATPase of the sarcoplasmic reticulum (SERCA2) by means of double and triple immunostaining protocols clearly demonstrates that cholesterol is primarily localized to the sarcoplasmic reticulum membranes of skeletal muscle rather than the sarcolemmal or T tubule membranes. The availability of this reagent and its ability to spatially localize cholesterol in situ may provide a greater understanding of the relationship between membrane cholesterol content and transmembrane signaling in skeletal muscle.

immunolocalization; sarcoplasmic reticulum


To Advertise     Find Products


Science Signaling. ISSN 1937-9145 (online), 1945-0877 (print). Pre-2008: Science's STKE. ISSN 1525-8882