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Updated: May 28, 2026

Experimental Approaches to Study Mitochondrial Localization and Function of a Nuclear Cell Cycle Kinase, Cdk1
Published on: February 25, 2016
Mitochondrial localization unveils a novel role for GRK2 in organelle biogenesis
Anna Fusco1, Gaetano Santulli1, Daniela Sorriento1
1Clinical Medicine, Cardiovascular and Immunological Sciences "Federico II" University, Naples, Italy.
Abstract:
Metabolic stimuli such as insulin and insulin like growth factor cause cellular accumulation of G protein coupled receptor kinase 2 (GRK2), which in turn is able to induce insulin resistance. Here we show that in fibroblasts, GRK2 is able to increase ATP cellular content by enhancing mitochondrial biogenesis; also, it antagonizes ATP loss after hypoxia/reperfusion. Interestingly, GRK2 is able to localize in the mitochondrial outer membrane, possibly through one region within the RGS homology domain and one region within the catalytic domain. In vivo, GRK2 removal from the skeletal muscle results in reduced ATP production and impaired tolerance to ischemia. Our data show a novel sub-cellular localization of GRK2 in the mitochondria and an unexpected role in regulating mitochondrial biogenesis and ATP generation.
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