IGF-1 stimulates muscle growth by suppressing protein breakdown and expression of atrophy-related ubiquitin-ligases, atrogin-1 and MuRF1
نویسندگان
چکیده
1Department of Cell Biology, Harvard Medical School, 240 Longwood Avenue, Boston, MA 02115, USA. 2Department of Biochemical Science and Technology, Faculty of Agriculture, Kagoshima University, 1-21-24 Korimoto, Kagoshima, Japan 890-0065 *J.M.S and A.O. contributed equally to this work. Correspondence should be addressed to: Alfred L. Goldberg Phone: (617) 432-1854 Fax: (617) 232-0173 e-mail: [email protected]
منابع مشابه
IGF-I stimulates muscle growth by suppressing protein breakdown and expression of atrophy-related ubiquitin ligases, atrogin-1 and MuRF1.
Muscle atrophy results primarily from accelerated protein degradation and is associated with increased expression of two muscle-specific ubiquitin ligases (E3s): atrogin-1 and muscle ring finger 1 (MuRF1). Glucocorticoids are essential for many types of muscle atrophy, and their effects are opposite to those of insulin-like growth factor I (IGF-I) and insulin, which promote growth. In myotubes,...
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Muscle atrophy in many conditions share a common mechanism in the upregulation of the muscle-specific ubiquitin E3-ligases atrophy gene-1/muscle atrophy F-box (Atrogin-1/MAFbx) and muscle ring-finger protein 1 (MuRF1). E3-ligases are part of the ubiquitin proteasome pathway utilized for protein degradation during muscle atrophy. In this study, we provide new data to show that this is not the ca...
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