Elevated levels of a calcium-activated muscle protease in rapidly atrophying muscles from vitamin E-deficient rabbits

William R. Dayton, Judith V. Schollmeyer, Alvin C. Chan, C. Eugene Allen

Research output: Contribution to journalArticlepeer-review

56 Scopus citations


A Ca2+-activated proteolytic enzyme * that partially degrades myofibrials was isolated from hind limb muscles of normal rabbits and rabbits undergoing rapid muscle atrophy as a result of vitamin E deficiency. Extractable Ca2+-activated protease activity was 3.6 times higher in muscle tissue from vitamin E-deficient rabbits than from muscle tissue of control rabbits. Ultrastructural studies of muscle from vitamin E-deficient rabbits showed that the Z disk was the first myofibrillar structure to show degradative changes in atrophying muscle. Myofibris prepared from muscles vitamin E-deficient rabbits showed partial or complete loss of Z-disk density. Sodium dodecyl sulfate polyacrylamide gel electrophoresis showed that the amount of troponin-T (37 000 daltons) and α-actinin (96 000 daltons) was reduced in myofibrils from atrophying muscle as compared to myofibrils prepared from control muscle. In vitro treatment of purified myofibrils with purified Ca2+-activated proteolytic enzyme produced alterations in myofibrillar ultrastructure that were identical to the initial alterations occuring in myofibrils from atrophying muscle (i.e. weakening and subsequent removal of Z disks). Additionally the electrophoretic banding pattern of Ca2+-activated proteolytic enzyme-treated myofibrils is very similar to that of myofibrils prepared from muscles atrophying as a result of nutritional vitamin E deficiency. The possible role of Ca2+-activated proteolytic enzyme in disassembly and degradation of the myofibril is discussed.

Original languageEnglish (US)
Pages (from-to)216-230
Number of pages15
JournalBBA - General Subjects
Issue number2
StatePublished - May 2 1979

Bibliographical note

Funding Information:
This work was supported by a grant from the University of Minnesota Graduate School and by a grant from the Minnesota Heart Association. This is Scientific Journal Series Paper No. 10 670, Minnesota Agricultural Experiment Station, University of Minnesota, St. Paul, MN 55108, U.S.A.

Copyright 2014 Elsevier B.V., All rights reserved.


  • (Rabbit muscle)
  • Ca activation
  • Myofibril
  • Protease
  • Vitamin E

Fingerprint Dive into the research topics of 'Elevated levels of a calcium-activated muscle protease in rapidly atrophying muscles from vitamin E-deficient rabbits'. Together they form a unique fingerprint.

Cite this