Figure 3.
Regulation of glucokinse activity in liver by liver specific GCK regulatory protein (GCKRP). In hepatocytes, in contrast to glucose sensing cells in regulation of glucose homeostasis, there is a specific inhibitory protein that regulates GCK activity. The figure schematically represents the association of GCK and GCKRP and the metabolic factors that affect that interaction. This can be considered a “switch” that turns enzyme activity on when blood glucose in elevated and off when it is low relative to normal (for background and details, see Zelent et al. (2014). SL, small lobe; LL, large lobe; ARR, allosteric regulatory region; SIS-1, sugar isomerase; SIS-2, sugar isomerase-2; LID, lid.