Giant mitochondria do not fuse and exchange their contents with normal mitochondria
- Department of Chemistry, University of Minnesota, 207 Pleasant St. SE, Minneapolis, MN (United States)
- Division of Geriatric Medicine, Faculty of Health Sciences, Linkoeping University, Linkoeping (Sweden)
Giant mitochondria accumulate within aged or diseased postmitotic cells as a consequence of insufficient autophagy, which is normally responsible for mitochondrial degradation. We report that giant mitochondria accumulating in cultured rat myoblasts due to inhibition of autophagy have low inner membrane potential and do not fuse with each other or with normal mitochondria. In addition to the low inner mitochondrial membrane potential in giant mitochondria, the quantity of the OPA1 mitochondrial fusion protein in these mitochondria was low, but the abundance of mitofusin-2 (Mfn2) remained unchanged. The combination of these factors may explain the lack of mitochondrial fusion in giant mitochondria and imply that the dysfunctional giant mitochondria cannot restore their function by fusing and exchanging their contents with fully functional mitochondria. These findings have important implications for understanding the mechanisms of accumulation of age-related mitochondrial damage in postmitotic cells.
- OSTI ID:
- 21045923
- Journal Information:
- Experimental Cell Research, Vol. 314, Issue 1; Other Information: DOI: 10.1016/j.yexcr.2007.09.013; PII: S0014-4827(07)00431-4; Copyright (c) 2007 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA); ISSN 0014-4827
- Country of Publication:
- United States
- Language:
- English
Similar Records
Resveratrol stimulates mitochondrial fusion by a mechanism requiring mitofusin-2
Loss of Drp1 function alters OPA1 processing and changes mitochondrial membrane organization