AMPK signaling pathway, a fuel sensor and regulator, promotes ATP-producing and inhibits ATP-consuming pathways in various tissues. AMPK is a heterotrimer composed of alpha-catalytic and beta and gamma-regulatory subunits. Cellular stresses that inhibit ATP production or increase its consumption change the AMP:ATP ratio and activate the pathway. Any metabolic stress that disrupts energy balance by interfering with ATP synthesis activates AMPK, such as glucose deprivation.
