Non-catalytic subunit of AMP-activated protein kinase (AMPK),an energy sensor protein kinase that plays a key role in regulating cellular energy metabolism.In response to reduction of intracellular ATP levels,AMPK activates energy-producing pathways and inhibits energy-consuming processes: inhibits protein,carbohydrate and lipid biosynthesis,as well as cell growth and proliferation.AMPK acts via direct phosphorylation of metabolic enzymes,and by longer-term effects via phosphorylation of transcription regulators.Also acts as a regulator of cellular polarity by remodeling the actin cytoskeleton;probably by indirectly activating myosin.Beta non-catalytic subunit acts as a scaffold on which the AMPK complex assembles,via its C-terminus that bridges alpha (PRKAA1 or PRKAA2) and gamma subunits (PRKAG1,PRKAG2 or PRKAG3).