The level of the glycogen targetting regulatory subunit R5 of protein phosphatase 1 is decreased in the livers of insulin-dependent diabetic rats and starved rats.

@article{Browne2001TheLO,
  title={The level of the glycogen targetting regulatory subunit R5 of protein phosphatase 1 is decreased in the livers of insulin-dependent diabetic rats and starved rats.},
  author={Gareth J. Browne and Mirela Delibegovi{\'c} and Stefaan Keppens and Willy Stalmans and Patricia Townsend Wade Cohen},
  journal={The Biochemical journal},
  year={2001},
  volume={360 Pt 2},
  pages={
          449-59
        }
}
Hepatic glycogen synthesis is impaired in insulin-dependent diabetic rats owing to defective activation of glycogen synthase by glycogen-bound protein phosphatase 1 (PP1). The identification of three glycogen-targetting subunits in liver, G(L), R5/PTG and R6, which form complexes with the catalytic subunit of PP1 (PP1c), raises the question of whether some or all of these PP1c complexes are subject to regulation by insulin. In liver lysates of control rats, R5 and R6 complexes with PP1c were… 

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A novel glycogen‐targeting subunit of protein phosphatase 1 that is regulated by insulin and shows differential tissue distribution in humans and rodents

It is shown here that the mammalian gene PPP1R3E encodes a novel glycogen‐targeting subunit of PP1 that is expressed in rodent liver that is downregulated in the livers of diabetic rodents and restored by insulin treatment.

Human skeletal muscle expresses a glycogen-targeting subunit of PP1 that is identical to the insulin-sensitive glycogen-targeting subunit G(L) of liver.

The species-specific difference in the level of expression of G(L) mRNA and protein in skeletal muscle has important implications for understanding the mechanisms by which insulin regulates glycogen synthesis in human skeletal muscle and for questions regarding whether rodents are appropriate models for this purpose.

Central Role for Protein Targeting to Glycogen in the Maintenance of Cellular Glycogen Stores in 3T3-L1 Adipocytes

Data indicate that disruption of PTG expression resulted in the uncoupling of PP1 activity from glycogen metabolizing enzymes, the enhancement of glycogenolysis, and a dramatic decrease in cellular glycogen levels, suggesting that PTG primarily acts to suppress glycogen breakdown.

Human Skeletal Muscle Expresses a Glycogen-Targeting Subunit of PP1 That Is Identical to the Insulin-Sensitive Glycogen-Targeting Subunit GL of Liver

The species-specific difference in the level of expression of GL mRNA and protein in skeletal muscle has important implications for understanding the mechanisms by which insulin regulates glycogen synthesis in human skeletal muscle and for questions regarding whether rodents are appropriate models for this purpose.

The PP 1R 6 protein phosphatase holoenzyme is involved in the glucose-induced dephosphorylation and inactivation of AMP-activated protein kinase , a key regulator of insulin secretion , in MIN 6 cells

The PP1-R6 protein phosphatase holoenzyme is involved in the glucoseinduced dephosphorylation and inactivation of AMPactivated protein kinase, a key regulator of insulin secretion, in MIN6 cells.

The PP1-R6 protein phosphatase holoenzyme is involved in the glucose-induced dephosphorylation and inactivation of AMP-activated protein kinase, a key regulator of insulin secretion, in MIN6 beta cells.

The characterization of the PP1-R6 complex identifies this holoenzyme as a possible target for therapeutic intervention with the aim of regulating the activity of AMPK in pancreatic β cells.

Differential Regulation of Glycogenolysis by Mutant Protein Phosphatase-1 Glycogen-targeting Subunits*

PTG and GL are hepatic protein phosphatase-1 (PP1) glycogen-targeting subunits, which direct PP1 activity against glycogen synthase (GS) and/or phosphorylase (GP). The C-terminal 16 amino residues of

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