TY - JOUR
T1 - Non-canonical activation of DAPK2 by AMPK constitutes a new pathway linking metabolic stress to autophagy
AU - Shiloh, Ruth
AU - Gilad, Yuval
AU - Ber, Yaara
AU - Eisenstein, Miriam
AU - Aweida, Dina
AU - Bialik, Shani
AU - Cohen, Shenhav
AU - Kimchi, Adi
N1 - We thank Y. Peleg and S. Albeck from the Structural Proteomics Unit at the Weizmann Institute of Science, for expression and purification of recombinant proteins, the Smoler Proteomic Center (Technion, Haifa, Israel) for performing the mass spectrometry analysis and Stephen Michnick for providing the plasmids of the Gaussia luciferase PCA (GLuc) system. This work was supported by a grant from European Research Council under the European Union’s Seventh Framework Program (FP7/2007-2013/ERC grant agreement 322709). A.K. is the Incumbent of the Helena Rubinstein Chair of Cancer Research.
PY - 2018/5/1
Y1 - 2018/5/1
N2 - Autophagy is an intracellular degradation process essential for adaptation to metabolic stress. DAPK2 is a calmodulin-regulated protein kinase, which has been implicated in autophagy regulation, though the mechanism is unclear. Here, we show that the central metabolic sensor, AMPK, phosphorylates DAPK2 at a critical site in the protein structure, between the catalytic and the calmodulin-binding domains. This phosphorylation activates DAPK2 by functionally mimicking calmodulin binding and mitigating an inhibitory autophosphorylation, providing a novel, alternative mechanism for DAPK2 activation during metabolic stress. In addition, we show that DAPK2 phosphorylates the core autophagic machinery protein, Beclin-1, leading to dissociation of its inhibitor, Bcl-X-L. Importantly, phosphorylation of DAPK2 by AMPK enhances DAPK2's ability to phosphorylate Beclin-1, and depletion of DAPK2 reduces autophagy in response to AMPK activation. Our study reveals a unique calmodulin-independent mechanism for DAPK2 activation, critical to its function as a novel downstream effector of AMPK in autophagy.
AB - Autophagy is an intracellular degradation process essential for adaptation to metabolic stress. DAPK2 is a calmodulin-regulated protein kinase, which has been implicated in autophagy regulation, though the mechanism is unclear. Here, we show that the central metabolic sensor, AMPK, phosphorylates DAPK2 at a critical site in the protein structure, between the catalytic and the calmodulin-binding domains. This phosphorylation activates DAPK2 by functionally mimicking calmodulin binding and mitigating an inhibitory autophosphorylation, providing a novel, alternative mechanism for DAPK2 activation during metabolic stress. In addition, we show that DAPK2 phosphorylates the core autophagic machinery protein, Beclin-1, leading to dissociation of its inhibitor, Bcl-X-L. Importantly, phosphorylation of DAPK2 by AMPK enhances DAPK2's ability to phosphorylate Beclin-1, and depletion of DAPK2 reduces autophagy in response to AMPK activation. Our study reveals a unique calmodulin-independent mechanism for DAPK2 activation, critical to its function as a novel downstream effector of AMPK in autophagy.
UR - http://www.scopus.com/inward/record.url?scp=85046427948&partnerID=8YFLogxK
U2 - https://doi.org/10.1038/s41467-018-03907-4
DO - https://doi.org/10.1038/s41467-018-03907-4
M3 - مقالة
SN - 2041-1723
VL - 9
JO - Nature Communications
JF - Nature Communications
IS - 1
M1 - 1759
ER -