PMID- 28647331
OWN - NLM
STAT- MEDLINE
DCOM- 20180531
LR  - 20211204
IS  - 1525-3198 (Electronic)
IS  - 0022-0302 (Linking)
VI  - 100
IP  - 9
DP  - 2017 Sep
TI  - Combination of histidine, lysine, methionine, and leucine promotes beta-casein 
      synthesis via the mechanistic target of rapamycin signaling pathway in bovine 
      mammary epithelial cells.
PG  - 7696-7709
LID - S0022-0302(17)30602-1 [pii]
LID - 10.3168/jds.2015-10729 [doi]
AB  - The ratio of different AA in the diets of cows is vital to improve milk protein 
      yield. beta-Casein is one of the important milk proteins with high nutritive value. 
      However, the suitable ratio of essential amino acids (EAA) for the expression of 
      beta-casein in the immortalized bovine mammary epithelial cell line is not fully 
      characterized. This study employed response surface methodology to determine the 
      optimal ratio of His, Lys, Met, and Leu on beta-casein expression level in vitro and 
      clarified the effect of the 4 EAA on beta-casein via the mechanistic target of 
      rapamycin (mTOR) signaling pathway. A central composite design containing 5 axial 
      points per EAA and 28 combinations of the 4 EAA was used in our study. The 
      results of response surface methodology and the changes of the mTOR-related 
      signaling proteins were determined by western blot. The results showed that 
      beta-casein level was significantly affected by all 4 EAA (R(2) = 0.71). The optimum 
      conditions for beta-casein expression are found to be 5.47 mM of His, 7.48 mM of 
      Lys, 1.17 mM of Met, and 8.21 mM of Leu (His:Lys:Met:Leu = 5:6:1:7) in the 
      designed scope of concentration. The interaction of Leu and Met significantly 
      affected beta-casein expression (P < 0.01). The phosphorylation of mTOR (Ser(2481)), 
      regulatory associated protein of target of rapamycin (Ser(792)), ribosomal 
      protein S6 kinase 1 (Thr(389)), ribosomal protein S6 (Ser(235/236)), and 
      eukaryotic elongation factor 2 (Thr(56)) was increased with the supplementation 
      of either single EAA or an optimal combination of EAA. However, the 
      phosphorylation of eukaryotic initiation factor 4E binding protein 1 (Thr(37)) 
      was decreased with the addition of Lys, Met, or Leu alone. Furthermore, the 
      phosphorylation (P) of eIF2alpha (Ser(51)) was decreased when Met was supplemented 
      alone. Under the optimal mixture of 4 EAA, the phosphorylation of mechanistic 
      target of rapamycin complex 1 signaling proteins was significantly greater than 
      the single EAA supplementations and the expression of beta-casein was 98% as high as 
      the positive control (i.e., medium with all AA). A similar trend was found with 
      P-ribosomal protein S6 kinase 1 and P-ribosomal protein S6. In conclusion, the 
      extracellular concentrations of His, Lys, Met, and Leu at a ratio of 5:6:1:7 
      maximized beta-casein expression in the immortalized bovine mammary epithelial cell 
      line may occur via activation of the mechanistic target of rapamycin complex 1 
      signaling pathway.
CI  - Copyright (c) 2017 American Dairy Science Association. Published by Elsevier Inc. 
      All rights reserved.
FAU - Gao, H N
AU  - Gao HN
AD  - Ministry of Agriculture-Milk Risk Assessment Laboratory, Institute of Animal 
      Science, Chinese Academy of Agricultural Sciences, Beijing 100193, China; College 
      of Animal Science and Technology, Gansu Agricultural University, Lanzhou 730070, 
      China; Ministry of Agriculture-Milk and Dairy Product Inspection Center, Beijing 
      100193, China; State Key Laboratory of Animal Nutrition, Institute of Animal 
      Science, Chinese Academy of Agricultural Sciences, Beijing 100193, China.
FAU - Zhao, S G
AU  - Zhao SG
AD  - Ministry of Agriculture-Milk Risk Assessment Laboratory, Institute of Animal 
      Science, Chinese Academy of Agricultural Sciences, Beijing 100193, China; 
      Ministry of Agriculture-Milk and Dairy Product Inspection Center, Beijing 100193, 
      China; State Key Laboratory of Animal Nutrition, Institute of Animal Science, 
      Chinese Academy of Agricultural Sciences, Beijing 100193, China.
FAU - Zheng, N
AU  - Zheng N
AD  - Ministry of Agriculture-Milk Risk Assessment Laboratory, Institute of Animal 
      Science, Chinese Academy of Agricultural Sciences, Beijing 100193, China; 
      Ministry of Agriculture-Milk and Dairy Product Inspection Center, Beijing 100193, 
      China; State Key Laboratory of Animal Nutrition, Institute of Animal Science, 
      Chinese Academy of Agricultural Sciences, Beijing 100193, China.
FAU - Zhang, Y D
AU  - Zhang YD
AD  - Ministry of Agriculture-Milk Risk Assessment Laboratory, Institute of Animal 
      Science, Chinese Academy of Agricultural Sciences, Beijing 100193, China; 
      Ministry of Agriculture-Milk and Dairy Product Inspection Center, Beijing 100193, 
      China; State Key Laboratory of Animal Nutrition, Institute of Animal Science, 
      Chinese Academy of Agricultural Sciences, Beijing 100193, China.
FAU - Wang, S S
AU  - Wang SS
AD  - Ministry of Agriculture-Milk Risk Assessment Laboratory, Institute of Animal 
      Science, Chinese Academy of Agricultural Sciences, Beijing 100193, China; 
      Ministry of Agriculture-Milk and Dairy Product Inspection Center, Beijing 100193, 
      China; State Key Laboratory of Animal Nutrition, Institute of Animal Science, 
      Chinese Academy of Agricultural Sciences, Beijing 100193, China.
FAU - Zhou, X Q
AU  - Zhou XQ
AD  - Ministry of Agriculture-Milk Risk Assessment Laboratory, Institute of Animal 
      Science, Chinese Academy of Agricultural Sciences, Beijing 100193, China; 
      Ministry of Agriculture-Milk and Dairy Product Inspection Center, Beijing 100193, 
      China; State Key Laboratory of Animal Nutrition, Institute of Animal Science, 
      Chinese Academy of Agricultural Sciences, Beijing 100193, China.
FAU - Wang, J Q
AU  - Wang JQ
AD  - Ministry of Agriculture-Milk Risk Assessment Laboratory, Institute of Animal 
      Science, Chinese Academy of Agricultural Sciences, Beijing 100193, China; College 
      of Animal Science and Technology, Gansu Agricultural University, Lanzhou 730070, 
      China; Ministry of Agriculture-Milk and Dairy Product Inspection Center, Beijing 
      100193, China; State Key Laboratory of Animal Nutrition, Institute of Animal 
      Science, Chinese Academy of Agricultural Sciences, Beijing 100193, China. 
      Electronic address: wang-jia-qi@263.net.
LA  - eng
PT  - Journal Article
DEP - 20170621
PL  - United States
TA  - J Dairy Sci
JT  - Journal of dairy science
JID - 2985126R
RN  - 0 (Caseins)
RN  - 4QD397987E (Histidine)
RN  - AE28F7PNPL (Methionine)
RN  - EC 2.7.11.1 (TOR Serine-Threonine Kinases)
RN  - GMW67QNF9C (Leucine)
RN  - K3Z4F929H6 (Lysine)
SB  - IM
MH  - Animals
MH  - Caseins/*biosynthesis
MH  - Cattle
MH  - Cell Line
MH  - Epithelial Cells/*metabolism
MH  - Female
MH  - Histidine/*administration & dosage
MH  - Leucine/*administration & dosage
MH  - Lysine/*administration & dosage
MH  - Mammary Glands, Animal/cytology/*metabolism
MH  - Methionine/*administration & dosage
MH  - Phosphorylation/drug effects
MH  - TOR Serine-Threonine Kinases/*metabolism
OTO - NOTNLM
OT  - bovine mammary epithelial cells
OT  - essential amino acid
OT  - mechanistic target of rapamycin
OT  - beta-casein
EDAT- 2017/06/26 06:00
MHDA- 2018/06/01 06:00
CRDT- 2017/06/26 06:00
PHST- 2015/12/06 00:00 [received]
PHST- 2017/02/22 00:00 [accepted]
PHST- 2017/06/26 06:00 [pubmed]
PHST- 2018/06/01 06:00 [medline]
PHST- 2017/06/26 06:00 [entrez]
AID - S0022-0302(17)30602-1 [pii]
AID - 10.3168/jds.2015-10729 [doi]
PST - ppublish
SO  - J Dairy Sci. 2017 Sep;100(9):7696-7709. doi: 10.3168/jds.2015-10729. Epub 2017 
      Jun 21.