TY - JOUR
T1 - Regulated step in cholesterol feedback localized to budding of SCAP from ER membranes
AU - Nohturfft, Axel
AU - Yabe, Daisuke
AU - Goldstein, Joseph L.
AU - Brown, Michael S.
AU - Espenshade, Peter J.
N1 - Funding Information:
We thank Amanda Hogle, Tammy Dinh, and Clinton Steffey for excellent technical assistance; Lisa Beatty, Jill Abadia, and Anna Fuller for invaluable help with tissue culture; Drs. Jennifer Lippincott-Schwartz, David Meyer, Kelley Moremen, Tom Rapoport, and Jaakko Saraste for generously providing antibodies and plasmids; and Dr. Richard Anderson for advice on confocal microscopy. This work was supported by grants from the National Institutes of Health (NIH) (HL-20948) and the Perot Family Foundation. P. J. E. is a recipient of an NIH Research Science Fellowship Grant (HL-09993).
PY - 2000/8/4
Y1 - 2000/8/4
N2 - SREBPs exit the ER in a complex with SCAP. Together, they move to the Golgi where SREBP is cleaved, releasing a fragment that activates genes encoding lipid biosynthetic enzymes. Sterols block ER exit, preventing cleavage, decreasing transcription, and achieving feedback control of lipid synthesis. Here, we report an in vitro system to measure incorporation of SCAP into ER vesicles. When membranes were isolated from sterol-depleted cells, SCAP entered vesicles in a reaction requiring nucleoside triphosphates and cytosol. SCAP budding was diminished in membranes from sterol-treated cells. Kinetics of induction of budding in vitro matched kinetics of ER exit in living cells expressing GFP-SCAP. These data localize the sterol-regulated step to budding of SCAP from ER and provide a system for biochemical dissection.
AB - SREBPs exit the ER in a complex with SCAP. Together, they move to the Golgi where SREBP is cleaved, releasing a fragment that activates genes encoding lipid biosynthetic enzymes. Sterols block ER exit, preventing cleavage, decreasing transcription, and achieving feedback control of lipid synthesis. Here, we report an in vitro system to measure incorporation of SCAP into ER vesicles. When membranes were isolated from sterol-depleted cells, SCAP entered vesicles in a reaction requiring nucleoside triphosphates and cytosol. SCAP budding was diminished in membranes from sterol-treated cells. Kinetics of induction of budding in vitro matched kinetics of ER exit in living cells expressing GFP-SCAP. These data localize the sterol-regulated step to budding of SCAP from ER and provide a system for biochemical dissection.
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U2 - 10.1016/S0092-8674(00)00037-4
DO - 10.1016/S0092-8674(00)00037-4
M3 - Article
C2 - 10975522
AN - SCOPUS:0034604350
SN - 0092-8674
VL - 102
SP - 315
EP - 323
JO - Cell
JF - Cell
IS - 3
ER -