Regulation of glycogen

Glycogen synthase kinase 3 (GSK3) is inactivated by insulin and lithium and, like insulin, Li also activates glycogen synthase (GS)viainhibition of GSK3. Li also mimics insu-lin’s ability to stimulate glucose transport (GT), an obser-vation that has led to the suggestion that GSK3 may coordinate hormonal increases in GT and glycogen synthe-sis. Here we have used Li and SB-415286, a selective GSK3 inhibitor, to establish the importance of GSK3 in the hor-monal activation of GT in terms of its effect on GS in L6 myotubes and3T3-L1adipocytes. ...

10p tumor12 20-04-2013 34 4   Download

14-3-3 Proteins are dimeric phophoserine-binding molecules that participate in important cellular processes such as cell proliferation, cell-cycle control and the stress response. In this work, we report that several isoforms of 14-3-3s are expressed in neonatal rat cardiomyocytes. To understand their function, we utilized a general 14-3-3 peptide inhibitor, R18, to disrupt 14-3-3 functions in cardiomyocytes.

0p awards 06-04-2013 38 1   Download

Stimulation of glycogen-targeted protein phosphatase 1 (PP1) activity by insulin contributes to the dephosphorylation and activation of hepatic gly-cogen synthase (GS) leading to an increase in glycogen synthesis. The gly-cogen-targeting subunits of PP1, GLand R5⁄PTG, are downregulated in the livers of diabetic rodents and restored by insulin treatment. We show here that the mammalian genePPP1R3Eencodes a novel glycogen-target-ing subunit of PP1 that is expressed in rodent liver.

12p awards 06-04-2013 31 5   Download

The Per-Arnt-Sim (PAS) domain serine⁄threonine kinase PASKIN, or PAS kinase, links energy flux and protein synthesis in yeast, regulates glycogen synthesis and protein translation in mammals, and might be involved in insulin regulation in the pancreas.

12p cosis54 05-01-2013 33 3   Download