RESEARCH ARTICLE
Signaling Pathways Related to Protein Synthesis and Amino Acid Concentration in Pig Skeletal Muscles Depend on the Dietary Protein Level, Genotype and Developmental Stages Yingying Liu1,2,5, Fengna Li1, Xiangfeng Kong1*, Bie Tan1, Yinghui Li1,5, Yehui Duan1,5, François Blachier3, Chien-An A. Hu4, Yulong Yin1,6,7*
OPEN ACCESS Citation: Liu Y, Li F, Kong X, Tan B, Li Y, Duan Y, et al. (2015) Signaling Pathways Related to Protein Synthesis and Amino Acid Concentration in Pig Skeletal Muscles Depend on the Dietary Protein Level, Genotype and Developmental Stages. PLoS ONE 10(9): e0138277. doi:10.1371/journal. pone.0138277 Editor: Zane Andrews, Monash University, AUSTRALIA Received: June 23, 2015 Accepted: August 27, 2015 Published: September 22, 2015 Copyright: © 2015 Liu et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Data Availability Statement: All relevant data are within the paper. Funding: The present work was jointly supported by grants from National Nature Science Foundation of China (31330075, 31110103909,31270044 and 31372325), the National Basic Research Program of China (No. 2012CB124704 and 2013CB127305), K. C. Wong Education Foundation(Hong Kong). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Changsha Lvye Biotechnology
1 Key Laboratory of Agro-ecological Processes in Subtropical Region, Chinese Academy of Sciences, Changsha, Hunan, China, 2 Hunan Animal Science and Veterinary Medicine Research Institute, Changsha, China, 3 INRA, CNRH-IdF, AgroParisTech, UMR 914 Nutrition Physiology and Ingestive Behavior, Paris, France, 4 Department of Biochemistry and Molecular Biology, University of New Mexico, Albuquerque, United States of America, 5 University of Chinese Academy of Sciences, Beijing, China, 6 School of Biology, Hunan Normal Univesity, Hunan, Changsha City, 410018, China, 7 Changsha Lvye Biotechnology Limited Company, Guangdong Hinapharm Group and WangDa Academician Workstation, Hunan, Changsha City, 41019, P. R. China *
[email protected] (XK);
[email protected] (YY)
Abstract Muscle growth is regulated by the homeostatic balance of the biosynthesis and degradation of muscle proteins. To elucidate the molecular interactions among diet, pig genotype, and physiological stage, we examined the effect of dietary protein concentration, pig genotype, and physiological stages on amino acid (AA) pools, protein deposition, and related signaling pathways in different types of skeletal muscles. The study used 48 Landrace pigs and 48 pure-bred Bama mini-pigs assigned to each of 2 dietary treatments: lower/GB (Chinese conventional diet)- or higher/NRC (National Research Council)-protein diet. Diets were fed from 5 weeks of age to respective market weights of each genotype. Samples of biceps femoris muscle (BFM, type I) and longissimus dorsi muscle (LDM, type II) were collected at nursery, growing, and finishing phases according to the physiological stage of each genotype, to determine the AA concentrations, mRNA levels for growth-related genes in muscles, and protein abundances of mechanistic target of rapamycin (mTOR) signaling pathway. Our data showed that the concentrations of most AAs in LDM and BFM of pigs increased (P
