TY - JOUR
T1 - Comparison of GLUT1, GLUT3, and GLUT4 mRNA and the subcellular distribution of their proteins in normal human muscle
AU - Stuart, Charles A.
AU - Wen, Gary
AU - Gustafson, W. Clay
AU - Thompson, E. Aubrey
N1 - Funding Information:
From the Departments of Internal Medicine and Human Biological Chemistry and Genetics, The University of Texas Medical Branch at Galveston, Galveston, TX. Submitted January 18, 2000; accepted May 16, 2000. Supported in part by grants from the National Institutes of Health (DK33749), the National Aeronautics and Space Administration (NAGW-4032), and the National Institutes of Health National Center for Research Resources General Clinical Research Center Program (MO1 RR00073). Address reprint requests to Charles A. Stuart, MD, The University of Texas Medical Branch at Galveston, 301 University Blvd, Galveston, TX 77555-1060. Copyright r 2000 by W.B. Saunders Company 0026-0495/00/4912-0015$10.00/0 doi:10.1053/meta.2000.18559
PY - 2000
Y1 - 2000
N2 - Basal, "insulin-independent" glucose uptake into skeletal muscle is provided by glucose transporters positioned at the plasma membrane. The relative amount of the three glucose transporters expressed in muscle has not been previously quantified. Using a combination of qualitative and quantitative ribonuclease protection assay (RPA) methods, we found in normal human muscle that GLUT1, GLUT3, and GLUT4 mRNA were expressed at 90 ± 10, 46 ± 4, and 156 ± 12 copies/ng RNA, respectively. Muscle was fractionated by DNase digestion and differential sedimentation into membrane fractions enriched in plasma membranes (PM) or low-density microsomes (LDM). GLUT1 and GLUT4 proteins were distributed 57% to 67% in LDM, whereas GLUT3 protein was at least 88% in the PM-enriched fractions. These data suggest that basal glucose uptake into resting human muscle could be provided in part by each of these three isoforms.
AB - Basal, "insulin-independent" glucose uptake into skeletal muscle is provided by glucose transporters positioned at the plasma membrane. The relative amount of the three glucose transporters expressed in muscle has not been previously quantified. Using a combination of qualitative and quantitative ribonuclease protection assay (RPA) methods, we found in normal human muscle that GLUT1, GLUT3, and GLUT4 mRNA were expressed at 90 ± 10, 46 ± 4, and 156 ± 12 copies/ng RNA, respectively. Muscle was fractionated by DNase digestion and differential sedimentation into membrane fractions enriched in plasma membranes (PM) or low-density microsomes (LDM). GLUT1 and GLUT4 proteins were distributed 57% to 67% in LDM, whereas GLUT3 protein was at least 88% in the PM-enriched fractions. These data suggest that basal glucose uptake into resting human muscle could be provided in part by each of these three isoforms.
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U2 - 10.1053/meta.2000.18559
DO - 10.1053/meta.2000.18559
M3 - Article
C2 - 11145124
AN - SCOPUS:0034535380
SN - 0026-0495
VL - 49
SP - 1604
EP - 1609
JO - Metabolism: Clinical and Experimental
JF - Metabolism: Clinical and Experimental
IS - 12
ER -