Glycogen synthase, function

In contrast to inhibitor 1, DARPP-32 and NIPP1, which regulate signal transduction, the function of inhibitor 2 appears to be different. There is evidence that inhibitor 2 associates with PP1, as the phosphatase is newly synthesized and contributes to the proper folding of the enzyme [40]. Inhibitor 2 can thus be considered a chaperone protein. The inactive PP 1-inhibitor 2 complex can then be activated upon phosphorylation of inhibitor 2 by glycogen synthase kinase-3. Whether this process is regulated in neurons in association with synaptic activity remains unknown. 

A crucial kinase that functions as an intermediary in numerous intracellular signaling pathways is the enzyme glycogen synthase kinase-3 (GSK-3) 898... 

The complete deduced amino-acid sequences of the open reading frames of the Waxy genes from maize and barley are known. About 75% identity can be seen in the sequence with respect to amino acids. If functionally similar amino acids are considered, then the homology is about 81%. Thus, these two proteins are similar in sequence and probably carry out the same function in the starch granule. There is, however, very little sequence homology with the bacterial glycogen synthase beyond the N-terminal sequence. 

In humans, Li+ therapy is used in the clinical treatment of certain bipolar disorders (e.g., manic depression), where its action is presumed to be inhibition of abnormal PI signaling, due to a decrease in inositol substrate availability (Lachman and Papolos, 1989). More recent studies have indicated the presence of other Li+-sensitive enzymes in animals that may also function as in vivo targets for Li+ action in animal development. These include the inositol polyphosphate-1 phosphatase (IPPase) (York et al., 1995) and glycogen synthase kinase-3(3 (Klein and Melton, 1996). However, why inositol would rescue the phenotypes putatively caused by the inhibition of such enzymes remains unclear thus, this area is still ripe for experimentation that could reconcile these issues. 

Li L, Liu Z, Liu J Tai X, Hu X, Liu X et al (2013) Ginsenoside Rd attenuates beta-amyloid-induced tau phosphorylation by altering the functional balance of glycogen synthase kinase 3beta and protein phosphatase 2A. Neurobiol Dis 54 320-328... 

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