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Monitoring Kinase and Phosphatase Activities Through the Cell Cycle by Ratiometric FRET
Published on: January 27, 2012
Subcellular dynamics of protein kinase A activity visualized by FRET-based reporters
1Department of Pharmacology and Molecular Sciences, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
Abstract:
cAMP-dependent protein kinase (PKA) mediates key cellular processes via compartmentalized activity, and the ability to track its activity in living cells should help increase our understanding of this precise regulation. Here, through systematic testing of new fluorescent proteins, we developed a new FRET-based A-kinase activity reporter (AKAR), AKAR3, with a dynamic range of 31-41%, twice that of predecessors. Visualization of PKA activity at plasma membrane, cytoplasm, nucleus, and mitochondria was achieved. Targeting AKAR3 to outer mitochondrial membrane revealed that basal PKA activity at mitochondria differs from that in the cytoplasm, indicating differential regulation of PKA activity at different subcellular locations.
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