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Updated: Jul 10, 2026
08:05
Assaying Protein Kinase Activity with Radiolabeled ATP
Published on: May 26, 2017
Structure and function of the protein kinase R
1Monash Institute of Medical Research, Monash University, Melbourne, Victoria 3168, Australia.
Current Topics in Microbiology and Immunology
|November 1, 2007
Summary
Protein Kinase R (PKR) acts as a cellular stress sensor, activated by viral dsRNA and other molecules. It regulates protein synthesis and has broader roles in cell signaling, disease, and normal cell functions.
Area of Science:
- Molecular Biology
- Cellular Stress Response
- Signal Transduction
Background:
- Protein Kinase R (PKR) is an intracellular sensor.
- PKR is activated by double-stranded RNA (dsRNA) during viral infections.
- Activation of PKR arrests protein synthesis by phosphorylating eIF2.
Purpose of the Study:
- To explore the multifaceted roles of PKR beyond viral infection.
- To highlight PKR's function as a signaling molecule for diverse physiological stresses.
- To investigate PKR's involvement in various cellular processes and diseases.
Main Methods:
- Review of existing literature on PKR activation and substrates.
- Analysis of PKR's role in response to multiple stimuli (dsRNA, PACT, heparin, etc.).
- Examination of PKR's substrates and their implications in cellular regulation.
Main Results:
- PKR is activated by dsRNA, PACT, and heparin, responding to indirect stimuli like LPS and ceramide.
- PKR regulates protein synthesis and has additional substrates involved in transcription and signal transduction.
- PKR is implicated in tumorigenesis, neurodegenerative diseases, cell differentiation, and calcification.
Conclusions:
- PKR functions as a versatile signaling molecule, sensing a wide array of cellular stresses.
- PKR's substrates support its roles in both infected and uninfected cells, impacting disease pathogenesis.
- PKR is crucial for normal cellular processes like differentiation and calcification, in addition to stress responses.
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