PMID- 26394157 OWN - NLM STAT- MEDLINE DCOM- 20160603 LR - 20220311 IS - 1932-6203 (Electronic) IS - 1932-6203 (Linking) VI - 10 IP - 9 DP - 2015 TI - Signaling Pathways Related to Protein Synthesis and Amino Acid Concentration in Pig Skeletal Muscles Depend on the Dietary Protein Level, Genotype and Developmental Stages. PG - e0138277 LID - 10.1371/journal.pone.0138277 [doi] LID - e0138277 AB - 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<0.05) gradually with increasing age. Bama mini-pigs had generally higher (P<0.05) muscle concentrations of flavor-related AA, including Met, Phe, Tyr, Pro, and Ser, compared with Landrace pigs. The mRNA levels for myogenic determining factor, myogenin, myocyte-specific enhancer binding factor 2 A, and myostatin of Bama mini-pigs were higher (P<0.05) than those of Landrace pigs, while total and phosphorylated protein levels for protein kinase B, mTOR, and p70 ribosomal protein S6 kinases (p70S6K), and ratios of p-mTOR/mTOR, p-AKT/AKT, and p-p70S6K/p70S6K were lower (P<0.05). There was a significant pig genotype-dependent effect of dietary protein on the levels for mTOR and p70S6K. When compared with the higher protein-NRC diet, the lower protein-GB diet increased (P<0.05) the levels for mTOR and p70S6K in Bama mini-pigs, but repressed (P<0.05) the level for p70S6K in Landrace pigs. The higher protein-NRC diet increased ratio of p-mTOR/mTOR in Landrace pigs. These findings indicated that the dynamic consequences of AA profile and protein deposition in muscle tissues are the concerted effort of distinctive genotype, nutrient status, age, and muscle type. Our results provide valuable information for animal feeding strategy. FAU - Liu, Yingying AU - Liu Y AD - Key Laboratory of Agro-ecological Processes in Subtropical Region, Chinese Academy of Sciences, Changsha, Hunan, China; Hunan Animal Science and Veterinary Medicine Research Institute, Changsha, China; University of Chinese Academy of Sciences, Beijing, China. FAU - Li, Fengna AU - Li F AD - Key Laboratory of Agro-ecological Processes in Subtropical Region, Chinese Academy of Sciences, Changsha, Hunan, China. FAU - Kong, Xiangfeng AU - Kong X AD - Key Laboratory of Agro-ecological Processes in Subtropical Region, Chinese Academy of Sciences, Changsha, Hunan, China. FAU - Tan, Bie AU - Tan B AD - Key Laboratory of Agro-ecological Processes in Subtropical Region, Chinese Academy of Sciences, Changsha, Hunan, China. FAU - Li, Yinghui AU - Li Y AD - Key Laboratory of Agro-ecological Processes in Subtropical Region, Chinese Academy of Sciences, Changsha, Hunan, China; University of Chinese Academy of Sciences, Beijing, China. FAU - Duan, Yehui AU - Duan Y AD - Key Laboratory of Agro-ecological Processes in Subtropical Region, Chinese Academy of Sciences, Changsha, Hunan, China; University of Chinese Academy of Sciences, Beijing, China. FAU - Blachier, Francois AU - Blachier F AD - INRA, CNRH-IdF, AgroParisTech, UMR 914 Nutrition Physiology and Ingestive Behavior, Paris, France. FAU - Hu, Chien-An A AU - Hu CA AD - Department of Biochemistry and Molecular Biology, University of New Mexico, Albuquerque, United States of America. FAU - Yin, Yulong AU - Yin Y AD - Key Laboratory of Agro-ecological Processes in Subtropical Region, Chinese Academy of Sciences, Changsha, Hunan, China; School of Biology, Hunan Normal Univesity, Hunan, Changsha City, 410018, China; Changsha Lvye Biotechnology Limited Company, Guangdong Hinapharm Group and WangDa Academician Workstation, Hunan, Changsha City, 41019, P. R. China. LA - eng PT - Journal Article PT - Research Support, Non-U.S. Gov't DEP - 20150922 PL - United States TA - PLoS One JT - PloS one JID - 101285081 RN - 0 (Amino Acids) RN - 0 (Muscle Proteins) RN - 0 (RNA, Messenger) RN - 63231-63-0 (RNA) RN - EC 2.7.11.1 (Ribosomal Protein S6 Kinases, 70-kDa) RN - EC 2.7.11.1 (TOR Serine-Threonine Kinases) SB - IM MH - Amino Acids/*analysis/metabolism MH - Animal Feed MH - Animals MH - Chromatography, High Pressure Liquid MH - *Diet MH - Genotype MH - Muscle Proteins/genetics/*metabolism MH - Muscle, Skeletal/growth & development/*metabolism MH - RNA/isolation & purification/metabolism MH - RNA, Messenger/metabolism MH - Real-Time Polymerase Chain Reaction MH - Ribosomal Protein S6 Kinases, 70-kDa/metabolism MH - Signal Transduction MH - Swine MH - Swine, Miniature/genetics/growth & development/metabolism MH - TOR Serine-Threonine Kinases/metabolism MH - Time Factors MH - Transcriptome PMC - PMC4578863 COIS- Competing Interests: The author's have the following interests. Yulong Yin is employed by Changsha Lvye Biotechnology Limited Company, Guangdong Hinapharm Group and WangDa Academician Workstation. There are no patents, products in development or marketed products to declare. This does not alter the authors' adherence to all the PLOS ONE policies on sharing data and materials, as detailed online in the guide for authors. EDAT- 2015/09/24 06:00 MHDA- 2016/06/04 06:00 PMCR- 2015/09/22 CRDT- 2015/09/23 06:00 PHST- 2015/06/23 00:00 [received] PHST- 2015/08/27 00:00 [accepted] PHST- 2015/09/23 06:00 [entrez] PHST- 2015/09/24 06:00 [pubmed] PHST- 2016/06/04 06:00 [medline] PHST- 2015/09/22 00:00 [pmc-release] AID - PONE-D-15-27098 [pii] AID - 10.1371/journal.pone.0138277 [doi] PST - epublish SO - PLoS One. 2015 Sep 22;10(9):e0138277. doi: 10.1371/journal.pone.0138277. eCollection 2015.