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Assessment of Selective mRNA Translation in Mammalian Cells by Polysome Profiling
10:00

Assessment of Selective mRNA Translation in Mammalian Cells by Polysome Profiling

Published on: October 28, 2014

Death-associated protein kinase phosphorylates mammalian ribosomal protein S6 and reduces protein synthesis

Andrew M Schumacher1, Anastasia V Velentza, D Martin Watterson

  • 1Center for Drug Discovery and Chemical Biology, Northwestern University, 303 East Chicago Avenue, W-896, Chicago, Illinois 60611, USA.

Biochemistry
|November 8, 2006
PubMed

Insights

Death-associated protein kinase (DAPK) phosphorylates ribosomal protein S6, revealing a novel mechanism for regulating protein synthesis and offering new therapeutic targets for neurodegenerative disorders.

Area of Science:

  • Molecular Biology
  • Neuroscience
  • Biochemistry

Background:

  • Death-associated protein kinase (DAPK) is a key regulator of apoptosis and a potential therapeutic target for neurodegenerative diseases.
  • The precise physiological substrates and functions of DAPK in neuronal cells are not fully understood.

Purpose of the Study:

  • To identify endogenous substrates of DAPK.
  • To investigate the role of DAPK in protein synthesis regulation.

Main Methods:

  • Immunoprecipitation assays to detect DAPK-S6 association in rat brain.
  • In vitro kinase assays using purified 40S ribosomal subunits.
  • Translation assays in rabbit reticulocyte lysate and neuroblastoma cells.

Main Results:

  • Mammalian 40S ribosomal protein S6 was identified as a direct substrate of DAPK.
  • DAPK selectively phosphorylates S6 at serine 235.
  • DAPK-mediated S6 phosphorylation correlates with the suppression of protein synthesis.

Conclusions:

  • DAPK acts as an S6 kinase, directly phosphorylating S6 at serine 235.
  • DAPK plays a novel role in regulating translation, potentially through S6 phosphorylation.
  • This discovery provides new insights into DAPK's function in neuronal pathophysiology and disease treatment.

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