Exploring the Role of PGC‐1α in Defining Nuclear Organisation in Skeletal Muscle Fibres. Issue 6 (29th December 2016)

• Record Type: Journal Article
• Authors: Ross, Jacob Alexander; Pearson, Adam; Levy, Yotam; Cardel, Bettina; Handschin, Christoph; Ochala, Julien
• Is Part Of: Journal of cellular physiology. Volume 232:Issue 6(2017:Jun.)
• Page Start: 1270
• Page End: 1274
• Publication Date: 2016-12-29
• Subjects: Physiology -- Periodicals; Cell physiology -- Periodicals; 571.6
• DOI: 10.1002/jcp.25678
• Languages: English
• ISSNs: 0021-9541

Abstract

Abstract : Muscle fibres are multinucleated cells, with each nucleus controlling the protein synthesis in a finite volume of cytoplasm termed the myonuclear domain (MND). What determines MND size remains unclear. In the present study, we aimed to test the hypothesis that the level of expression of the transcriptional coactivator PGC‐1α and subsequent activation of the mitochondrial biogenesis are major contributors. Hence, we used two transgenic mouse models with varying expression of PGC‐1α in skeletal muscles. We isolated myofibres from the fast twitch extensor digitorum longus (EDL) and slow twitch diaphragm muscles. We then membrane‐permeabilised them and analysed the 3D spatial arrangements of myonuclei. In EDL muscles, when PGC‐1α is over‐expressed, MND volume decreases; whereas, when PGC‐1α is lacking, no change occurs. In the diaphragm, no clear difference was noted. This indicates that PGC‐1α and the related mitochondrial biogenesis programme are determinants of MND size. PGC‐1α may facilitate the addition of new myonuclei in order to reach MND volumes that can support an increased mitochondrial density. J. Cell. Physiol. 232: 1270–1274, 2017. © 2016 Wiley Periodicals, Inc. Abstract : Muscle fibres are multinucleated cells, with individual nuclei controlling the protein synthesis in a finite volume of cytoplasm termed myonuclear domain. The present study indicates that one important regulator of myonuclear domain size is PGC‐1α and related mitochondrial biogenesis programme.