-!- This is a heterogeneous group of serine/threonine protein kinases that do not have an activating compound and are either non-specific or their specificity has not been analyzed to date. -!- Formerly EC 2.7.1.37 and EC 2.7.1.70.

-!- Activated by tubulin. -!- Involved in the formation of paired helical filaments, which are the main fibrous component of all fibrillary lesions in brain and are associated with Alzheimer's disease. -!- Formerly EC 2.7.1.135.

-!- Requires calmodulin for activity. -!- The enzyme phosphorylates a specific serine residue in each of the subunits of the dimeric phosphorylase b. -!- For muscle phosphorylase but not liver phosphorylase, this is accompanied by a further dimerization to form a tetrameric phosphorylase. -!- The enzyme couples muscle contraction with energy production via glycogenolysis--glycolysis by catalyzing the Ca(2+)-dependent phosphorylation and activation of glycogen phosphorylase b. -!- The gamma subunit of the tetrameric alpha-beta-gamma-delta enzyme is the catalytic subunit. -!- Formerly EC 2.7.1.38.