Published by Blackwell Pub. on behalf of the Federation of European Biochemical Societies
FEBS Journal vol:278 issue:21 pages:3978-3990
All life forms on earth require a continuous input and monitoring of carbon and energy supplies. The AMPK/SNF1/SnRK1 protein kinases are evolutionarily conserved metabolic sensors found in all eukaryotic organisms from simple unicellular fungi (yeast SNF1, Sucrose non-fermenting1) to animals (AMPK, AMP-activated kinase) and plants (SnRK1, Snf1-related kinase1). Activated by starvation and energy-depleting stress conditions, they enable energy homeostasis and survival by up-regulating energy-conserving and -producing catabolic processes, and by limiting energy-consuming anabolic metabolism. In addition, they control normal growth and development as well as metabolic homeostasis at the organismal level. As such, the AMPK/SNF1/SnRK1 kinases act in concert with other central signaling components to control carbohydrate uptake and metabolism, fatty acid and lipid biosynthesis and storage of carbon energy reserves. Moreover, they have a tremendous impact on developmental processes triggered by environmental changes such as nutrient depletion or stress. Although intensive research by many groups partly unveiled the factors that regulate AMPK/SNF1/SnRK1 kinase activity as well as the pathways and substrates it controls, several fundamental issues still await to be clarified. In this review, we will highlight these issues and focus on the structure, function and regulation of the AMPK/SNF1/SnRK1 kinases.