Abstract
Examination of the time and temperature dependence of insulin-stimulated GLUT4/IRAP-containing vesicle trafficking demonstrated an approximate 7-fold increase in the half-time for plasma membrane translocation at 23 °C (t( 1/2 ) = ~30 min) compared with 37 °C (t( 1/2 ) = ~4 min) without a significant change in the extent of either GLUT4 or IRAP translocation. Localization of the endogenous GLUT4 and expressed GLUT4-enhanced green fluorescent protein fusion protein in intact 3T3L1 adipocytes demonstrated that at 23°C there was a time-dependent accumulation of discrete GLUT4-containing vesicles adjacent to the inner face of the cell surface membrane but that was not contiguous and/or physically incorporated into the plasma membrane. Together, these data demonstrate that the temperature-dependent decrease in the rate of GLUT4 and IRAP translocation results from a reduction in GLUT4/IRAP- containing vesicle fusion and not trafficking or docking to the plasma membrane.
Original language | English (US) |
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Pages (from-to) | 37357-37361 |
Number of pages | 5 |
Journal | Journal of Biological Chemistry |
Volume | 274 |
Issue number | 52 |
DOIs | |
State | Published - Dec 24 1999 |
Externally published | Yes |
ASJC Scopus subject areas
- Biochemistry
- Molecular Biology
- Cell Biology