Characterization of a major protein in GLUT4 vesicles. Concentration in the vesicles and insulin-stimulated translocation to the plasma membrane

• Published in: The Journal of biological chemistry 1994-02, Vol.269 (8), p.6089-6092
• Main Authors: MASTICK, C. C, AEBERSOLD, R, LIENHARD, G. E
• Format: Article
• Language: English
• Subjects: Adipocytes - drug effects; Adipocytes - metabolism; Amino Acid Sequence; Analytical, structural and metabolic biochemistry; Animals; Antibodies - immunology; Biological and medical sciences; Biological Transport; Cell Membrane - metabolism; Fundamental and applied biological sciences. Psychology; Glucose Transporter Type 4; Insulin - pharmacology; Miscellaneous; Molecular Sequence Data; Monosaccharide Transport Proteins - metabolism; Muscle Proteins; Peptides - metabolism; Proteins; Proteins - immunology; Proteins - metabolism; Rats; Rats, Sprague-Dawley; Subcellular Fractions - metabolism
• ISSN: 0021-9258; 1083-351X
• DOI: 10.1016/s0021-9258(17)37573-7

GLUT4-enriched vesicles from fat and muscle cells contain a major protein of 165 kDa. In the present study we have prepared GLUT4 vesicles from a large number of rat adipocytes, isolated the 165-kDa protein by SDS-gel electrophoresis, and obtained the sequences of four tryptic peptides. Comparison of the sequences with those in protein data banks showed that the 165-kDa protein had not previously been sequenced. An antibody preparation against one of the peptides immunoblotted the 165-kDa protein. By this means it was found that the 165-kDa protein was concentrated in GLUT4 vesicles, and that insulin treatment of rat adipocytes caused a translocation of the protein to the plasma membrane that paralleled the translocation of GLUT4.