Transcriptional peroxisome proliferator-activated receptor γ coactivator-1 (PGC-1α) regulates transformation of muscle fiber type in Schizothorax prenanti

Abstract

Peroxisome proliferator-activated receptor γ coactivator (PGC)-1ɑ, a well-known member of PGC-1 transcriptional coactivator’s family, plays a key role in various metabolic pathways. Here, we investigated the role of PGC-1ɑ in the transformation of muscle fiber type in Schizothorax prenanti. The expression of PGC-1ɑ was induced in S. prenanti muscles following fasting. Following the induction of PGC-1ɑ, the expressions of mitochondrial-related enzyme cytochrome c oxidase (COX), citrate synthase (CS) and cytochrome c oxidase IV was also increased in white muscles, but the expression of carnitine palmitoyltransferase II (CPT II) has no change in this condition. Notably, when the levels of PGC-1ɑ was upregulated in the condition of fasting, muscle fibres type II showed the characteristics of muscle fibres type I, with expressed myosin heavy chain I (MyHC I) and myoglobin (Mb), and suppressed myosin heavy chain II (MyHC II) in response to fasting. Therefore, we can draw conclusion that PGC-1ɑ up-regulates slow fiber type formation during the transformation of muscle fiber type in S. prenanti.

Keywords: PGC-1ɑ, muscle fiber type, transformation, Schizothorax prenanti, MyHC I, MyHC II