Neurochemical Research

, Volume 16, Issue 8, pp 869–873 | Cite as

The regulatory role of calmodulin in the proteolysis of individual neurofilament proteins by calpain

  • Gail V. W. Johnson
  • Jeffrey A. Greenwood
  • Anthony C. Costello
  • Juan C. Troncoso
Original Articles


The in vitro degradation of individual neurofilament proteins by calpain and the effects of calmodulin on this proteolysis were studied. Two major results are reported. First, in the presence of calcium, calmodulin binds to the 200-kD neurofilament protein, but only weakly associates with the 150-kD neurofilament protein. The 70-kD neurofilament protein shows no specific calmodulin-binding. Second, calmodulin inhibits the calpain-mediated degradation of the 200-kD neurofilament protein, but does not alter the hydrolysis of the 150-kD and 70-kD neurofilament proteins. In addition, calmodulin is able to bind to the 200-kD neurofilament protein in the presence of other neurofilament subunits, indicating that calmodulin may play a role in the regulation of the metabolism of the 200-kD neurofilament protein in vivo.

Key Words

Neurofilaments calpain calmodulin proteolysis 


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Copyright information

© Plenum Publishing Corporation 1991

Authors and Affiliations

  • Gail V. W. Johnson
    • 1
  • Jeffrey A. Greenwood
    • 1
  • Anthony C. Costello
    • 2
  • Juan C. Troncoso
    • 2
    • 3
  1. 1.Department of Psychiatry and Behavioral Neurobiology, Sparks Center Room 911University of Alabama at BirminghamBirmingham
  2. 2.Neuropathology LaboratoryThe Johns Hopkins University School of MedicineBaltimore
  3. 3.Departments of Pathology and NeurologyThe Johns Hopkins University School of MedicineBaltimore

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