Sci. Signal., 21 June 2011
Metabolism Ramping Up AMPK
L. Bryan Ray
Science, Science Signaling, AAAS, Washington, DC 20005, USA
The adenosine monophosphate (AMP)–activated protein kinase (AMPK) senses depletion of energy stores (the accumulation of AMP) and activates appropriate metabolic responses to control cellular and organismal energy balance. But its name does not tell the whole story. The energy status of a cell is reflected in the "adenylate charge" or ratio of the concentration of adenosine triphosphate (ATP) to those of adenosine diphosphate (ADP) and AMP. Oakhill et al. (see the Perspective by Bland and Birnbaum) show that activity of AMPK is also highly sensitive to the concentration of ADP, as well as that of AMP. Like AMP, ADP bound to AMPK and promoted its activating phosphorylation by other protein kinases. ADP also inhibited dephosphorylation of AMPK, which inactivates the kinase. Because AMP can be rapidly deaminated in cells, sensing of ADP, as well as AMP, may be critical for the control of AMPK, which regulates a broad spectrum of biological responses from metabolism and metabolic diseases to the growth of cancer.
Citation: L. B. Ray, Ramping Up AMPK. Sci. Signal. 4, ec174 (2011).
The editors suggest the following Related Resources on Science sites:
In Science Signaling
Science Signaling. ISSN 1937-9145 (online), 1945-0877 (print). Pre-2008: Science's STKE. ISSN 1525-8882