Parallel comparative proteomics and phosphoproteomics reveal that cattle myostatin regulates phosphorylation of key enzymes in glycogen metabolism and glycolysis pathway

// Shuping Yang 1 , Xin Li 1 , Xinfeng Liu 1 , Xiangbin Ding 1 , Xiangbo Xin 1 , Congfei Jin 1 , Sheng Zhang 3 , Guangpeng Li 2 and Hong Guo 1 1 College of Animal Science and Veterinary Medicine, Tianjin Agricultural University, Tianjin 300384, China 2 The Key Laboratory of Mammalian Reproductive Biology and Biotechnology of the Ministry of Education, Inner Mongolia University, Hohhot 010070, China 3 Institute of Biotechnology, Cornell University, Ithaca, NY 14853, U.S.A Correspondence to: Hong Guo, email: guohong64@163.com Guangpeng Li, email: gpeng@imu.edu.cn Sheng Zhang, email: sz14@cornell.edu Keywords: myostatin, proteome, phosphoproteome, glycolysis, glycogenolysis Received: June 06, 2017      Accepted: September 23, 2017      Published: January 13, 2018 ABSTRACT MSTN -encoded myostatin is a negative regulator of skeletal muscle development. Here, we utilized the gluteus tissues from MSTN gene editing and wild type Luxi beef cattle which are native breed of cattle in China, performed tandem mass tag (TMT) -based comparative proteomics and phosphoproteomics analyses to investigate the regulatory mechanism of MSTN related to cellular metabolism and signaling pathway in muscle development. Out of 1,315 proteins, 69 differentially expressed proteins (DEPs) were found in global proteomics analysis. Meanwhile, 149 differentially changed phosphopeptides corresponding to 76 unique phosphorylated proteins (DEPPs) were detected from 2,600 identified phosphopeptides in 702 phosphorylated proteins. Bioinformatics analyses suggested that majority of DEPs and DEPPs were closely related to glycolysis, glycogenolysis, and muscle contractile fibre processes. The global discovery results were validated by Multiple Reaction Monitoring (MRM)-based targeted peptide quantitation analysis, western blotting, and muscle glycogen content measurement. Our data revealed that increase in abundance of key enzymes and phosphorylation on their regulatory sites appears responsible for the enhanced glycogenolysis and glycolysis in MSTN −/− . The elevated glycogenolysis was assocaited with an enhanced phosphorylation of Ser1018 in PHKA1, and Ser641/Ser645 in GYS1, which were regulated by upstream phosphorylated AKT-GSK3β pathway and highly consistent with the lower glycogen content in gluteus of MSTN −/− . Collectively, this study provides new insights into the regulatory mechanisms of MSTN involved in energy metabolism and muscle growth.