PMID- 30219419
OWN - NLM
STAT- MEDLINE
DCOM- 20190108
LR  - 20211204
IS  - 1525-3198 (Electronic)
IS  - 0022-0302 (Linking)
VI  - 101
IP  - 11
DP  - 2018 Nov
TI  - Seryl-tRNA synthetase-mediated essential amino acids regulate beta-casein synthesis 
      via cell proliferation and mammalian target of rapamycin (mTOR) signaling pathway 
      in bovine mammary epithelial cells.
PG  - 10456-10468
LID - S0022-0302(18)30845-2 [pii]
LID - 10.3168/jds.2018-14568 [doi]
AB  - Essential amino acids (EAA) play an important role in promoting milk protein 
      synthesis in primary bovine mammary epithelial cells (BMEC). However, the 
      regulatory mechanisms involved in the relationship between EAA and milk protein 
      synthesis have not been fully explored. This study examined the effects of 
      seryl-tRNA synthetase (SARS) on EAA-stimulated beta-casein synthesis, cell 
      proliferation, and the mammalian target of rapamycin (mTOR) system in BMEC. 
      First, BMEC were cultured in medium either lacking all EAA (-EAA) or that 
      included all EAA (+EAA) for 12 h. The BMEC were then supplemented with the 
      opposing treatments (-EAA supplemented with +EAA and vice versa) for 0 h, 10 min, 
      0.5 h, 1 h, 6 h, or 12 h, respectively. After the treatment-specific time 
      allotment, proteins were collected for Western blotting. Subsequently, a 2 x 2 
      factorial design was used to evaluate the interactive of SARS inhibition (control 
      or SARS inhibited) and EAA supply (+EAA or -EAA) on gene and protein abundance, 
      cell viability, and cell cycle in BMEC. Based on the data obtained in the first 
      experiment, the changes in protein abundance of beta-casein and SARS depended on EAA 
      treatment time in similar patterns. The protein abundance of beta-casein, SARS, and 
      mammalian target of rapamycin (mTOR)-related proteins, cell viability, cell cycle 
      progression, and the mRNA abundance of cyclin D1 (CCND1, cell cycle progression 
      marker) and marker of proliferation Ki-67 (MKI67, cell proliferation marker) were 
      stimulated by the presence of EAA. Correspondingly, when cells were deprived of 
      EAA, cell proliferation and abundance of these proteins and genes were reduced 
      overall. Moreover, the decreases in these aspects were further exacerbated by 
      inhibiting SARS, suggesting that an interaction between EAA and SARS is important 
      for regulating protein synthesis. The results indicated that SARS stimulated the 
      mTOR signaling pathway when EAA were present, enhanced EAA-stimulated cell 
      proliferation, and contributed to increased beta-casein production in BMEC.
CI  - Copyright (c) 2018 American Dairy Science Association. Published by Elsevier Inc. 
      All rights reserved.
FAU - Dai, W T
AU  - Dai WT
AD  - College of Animal Sciences, Zhejiang University, Hangzhou 310058, China.
FAU - White, R R
AU  - White RR
AD  - Department of Animal and Poultry Science, Virginia Tech, Blacksburg 24060.
FAU - Liu, J X
AU  - Liu JX
AD  - College of Animal Sciences, Zhejiang University, Hangzhou 310058, China.
FAU - Liu, H Y
AU  - Liu HY
AD  - Department of Animal and Poultry Science, Virginia Tech, Blacksburg 24060. 
      Electronic address: hyliu@zju.edu.cn.
LA  - eng
PT  - Journal Article
DEP - 20180913
PL  - United States
TA  - J Dairy Sci
JT  - Journal of dairy science
JID - 2985126R
RN  - 0 (Amino Acids, Essential)
RN  - 0 (Caseins)
RN  - 0 (Milk Proteins)
RN  - EC 2.7.11.1 (TOR Serine-Threonine Kinases)
RN  - EC 6.1.1.11 (Serine-tRNA Ligase)
SB  - IM
MH  - Amino Acids, Essential/*pharmacology
MH  - Animals
MH  - Caseins/metabolism
MH  - Cattle/*physiology
MH  - Cell Proliferation/drug effects
MH  - Dietary Supplements
MH  - Epithelial Cells/metabolism
MH  - Female
MH  - Mammary Glands, Animal/metabolism
MH  - Milk/*metabolism
MH  - Milk Proteins/metabolism
MH  - Phosphorylation
MH  - Serine-tRNA Ligase/drug effects/*metabolism
MH  - *Signal Transduction
MH  - TOR Serine-Threonine Kinases/genetics/*metabolism
OTO - NOTNLM
OT  - bovine mammary epithelial cells
OT  - cell proliferation
OT  - essential amino acids
OT  - mammalian target of rapamycin (mTOR)
OT  - beta-casein synthesis
EDAT- 2018/09/17 06:00
MHDA- 2019/01/09 06:00
CRDT- 2018/09/17 06:00
PHST- 2018/02/10 00:00 [received]
PHST- 2018/07/25 00:00 [accepted]
PHST- 2018/09/17 06:00 [pubmed]
PHST- 2019/01/09 06:00 [medline]
PHST- 2018/09/17 06:00 [entrez]
AID - S0022-0302(18)30845-2 [pii]
AID - 10.3168/jds.2018-14568 [doi]
PST - ppublish
SO  - J Dairy Sci. 2018 Nov;101(11):10456-10468. doi: 10.3168/jds.2018-14568. Epub 2018 
      Sep 13.