The decrease in the short variant of gsalpha protein is associated with an increase in [3H]CGP12177 binding, [3H]ouabain binding and Na, K-ATPase activity in brown adipose tissue plasma membranes of cold-acclimated hamsters.

L Bourová; J Novotn; P Svoboda

doi:10.1677/jme.0.0220055

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The decrease in the short variant of gsalpha protein is associated with an increase in [3H]CGP12177 binding, [3H]ouabain binding and Na, K-ATPase activity in brown adipose tissue plasma membranes of cold-acclimated hamsters.

L Bourová·J Novotn·P Svoboda

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Abstract

Sucrose density gradient purified plasma membranes isolated from brown adipose tissue of cold-acclimated hamsters (4-10 weeks at 0-4 degreesC) were analysed for the content of the short (GsalphaS) and long (GsalphaL) variants of Gsalpha protein (the alpha subunit of the stimulatory G protein) and compared with the membranes isolated from control animals. The relative ratio between the two variants (GsalphaS/GsalphaL) decreased from 0.48 to 0.24 (P<0.01). This result, obtained by electrophoretic resolution of membrane proteins by standard SDS-PAGE and an immunoblot analysis with an antiserum oriented against an internal sequence of Gsalpha, was verified by resolution on urea-containing gels and an antiserum oriented against the C-terminus decapeptide of Gsalpha. Under these conditions, the GsalphaS/GsalphaL ratio was decreased from 0.41 to 0.31 (P<0.05). The total amount of both isoforms (GsalphaS plus GsalphaL) decreased to 83% (P<0.05) or 68% (P<0.01) by standard or urea SDS-PAGE respectively. These data demonstrate that cold-acclimation of hamster brown adipose tissue is associated with preferential decrease in the plasma membrane density of the short variant of the Gsalpha protein.%This decrease was paralleled by an increase in the other plasma membrane constituents, [3H]CGP12177 binding sites, [3H]ouabain binding sites and Na,K-ATPase activity to 147%, 212% and 191% respectively.

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Acclimatization Adipose Tissue, Brown Animals Cell Membrane Centrifugation, Density Gradient Cold Temperature Cricetinae Enzyme Inhibitors GTP-Binding Protein alpha Subunits, Gs Membrane Proteins Mesocricetus Mitochondria Molecular Weight Ouabain Propanolamines Protein Isoforms Sodium-Potassium-Exchanging ATPase Journal Article Research Support, Non-U.S. Gov't

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L Bourová, J Novotn, P Svoboda. 1999. The decrease in the short variant of gsalpha protein is associated with an increase in [3H]CGP12177 binding, [3H]ouabain binding and Na, K-ATPase activity in brown adipose tissue plasma membranes of cold-acclimated hamsters.. https://doi.org/10.1677/jme.0.0220055

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