Activation of HMG-CoA reductase by microsomal phosphatase
HMG-CoA reductase activity can be modulated by a reversible phosphorylation-dephosphorylation with the phosphorylated form of the enzyme being inactive and the dephosphorylated form, active. Phosphatases from diverse sources, including cytosol, have been shown to dephosphorylate and activate HMG-CoA...
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1983-03-01
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Series: | Journal of Lipid Research |
Online Access: | http://www.sciencedirect.com/science/article/pii/S0022227520379979 |
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doaj-dba227b37619473aa49c35fea26411932021-04-24T05:50:19ZengElsevierJournal of Lipid Research0022-22751983-03-01243290296Activation of HMG-CoA reductase by microsomal phosphataseK R FeingoldM H WileyA H MoserS R LearM D SipersteinHMG-CoA reductase activity can be modulated by a reversible phosphorylation-dephosphorylation with the phosphorylated form of the enzyme being inactive and the dephosphorylated form, active. Phosphatases from diverse sources, including cytosol, have been shown to dephosphorylate and activate HMG-CoA reductase. The present study demonstrates phosphatase activity capable of activating HMG-CoA reductase that is associated with purified microsomes. The incubation of microsomes at 37 degrees C for 40 min results in a twofold stimulation of HMG-CoA reductase activity, and this stimulation is blocked by sodium fluoride or phosphate. The ability of microsomes to increase HMG-CoA reductase activity occurs regardless of whether microsomes are prepared by ultracentrifugation or calcium precipitation. Additionally, phosphatases capable of activating HMG-CoA reductase are present in both the smooth and rough endoplasmic reticulum. Freeze-thawing does not prevent microsomes from activating HMG-CoA reductase but preincubation results in a significant decrease in the ability of microsomes to increase HMG-CoA reductase activity. Thus, the present study demonstrates that purified liver microsomes contain phosphatase activity capable of activating HMG-CoA reductase.http://www.sciencedirect.com/science/article/pii/S0022227520379979 |
collection |
DOAJ |
language |
English |
format |
Article |
sources |
DOAJ |
author |
K R Feingold M H Wiley A H Moser S R Lear M D Siperstein |
spellingShingle |
K R Feingold M H Wiley A H Moser S R Lear M D Siperstein Activation of HMG-CoA reductase by microsomal phosphatase Journal of Lipid Research |
author_facet |
K R Feingold M H Wiley A H Moser S R Lear M D Siperstein |
author_sort |
K R Feingold |
title |
Activation of HMG-CoA reductase by microsomal phosphatase |
title_short |
Activation of HMG-CoA reductase by microsomal phosphatase |
title_full |
Activation of HMG-CoA reductase by microsomal phosphatase |
title_fullStr |
Activation of HMG-CoA reductase by microsomal phosphatase |
title_full_unstemmed |
Activation of HMG-CoA reductase by microsomal phosphatase |
title_sort |
activation of hmg-coa reductase by microsomal phosphatase |
publisher |
Elsevier |
series |
Journal of Lipid Research |
issn |
0022-2275 |
publishDate |
1983-03-01 |
description |
HMG-CoA reductase activity can be modulated by a reversible phosphorylation-dephosphorylation with the phosphorylated form of the enzyme being inactive and the dephosphorylated form, active. Phosphatases from diverse sources, including cytosol, have been shown to dephosphorylate and activate HMG-CoA reductase. The present study demonstrates phosphatase activity capable of activating HMG-CoA reductase that is associated with purified microsomes. The incubation of microsomes at 37 degrees C for 40 min results in a twofold stimulation of HMG-CoA reductase activity, and this stimulation is blocked by sodium fluoride or phosphate. The ability of microsomes to increase HMG-CoA reductase activity occurs regardless of whether microsomes are prepared by ultracentrifugation or calcium precipitation. Additionally, phosphatases capable of activating HMG-CoA reductase are present in both the smooth and rough endoplasmic reticulum. Freeze-thawing does not prevent microsomes from activating HMG-CoA reductase but preincubation results in a significant decrease in the ability of microsomes to increase HMG-CoA reductase activity. Thus, the present study demonstrates that purified liver microsomes contain phosphatase activity capable of activating HMG-CoA reductase. |
url |
http://www.sciencedirect.com/science/article/pii/S0022227520379979 |
work_keys_str_mv |
AT krfeingold activationofhmgcoareductasebymicrosomalphosphatase AT mhwiley activationofhmgcoareductasebymicrosomalphosphatase AT ahmoser activationofhmgcoareductasebymicrosomalphosphatase AT srlear activationofhmgcoareductasebymicrosomalphosphatase AT mdsiperstein activationofhmgcoareductasebymicrosomalphosphatase |
_version_ |
1721511826970116096 |