PMID- 29243067
OWN - NLM
STAT- MEDLINE
DCOM- 20180917
LR  - 20211204
IS  - 1573-4919 (Electronic)
IS  - 0300-8177 (Linking)
VI  - 445
IP  - 1-2
DP  - 2018 Aug
TI  - Translational regulation in the anoxic turtle, Trachemys scripta elegans.
PG  - 13-23
LID - 10.1007/s11010-017-3247-y [doi]
AB  - The red-eared slider turtle (Trachemys scripta elegans), has developed remarkable 
      adaptive mechanisms for coping with decreased oxygen availability during winter 
      when lakes and ponds become covered with ice. Strategies for enduring anoxia 
      tolerance include an increase in fermentable fuel reserves to support anaerobic 
      glycolysis, the buffering of end products to minimize acidosis, altered 
      expression in crucial survival genes, and strong metabolic rate suppression to 
      minimize ATP-expensive metabolic processes such as protein synthesis. The 
      mammalian target of rapamycin (mTOR) is at the center of the insulin-signaling 
      pathway that regulates protein translation. The present study analyzed the 
      responses of the mTOR signaling pathway to 5 (5H) or 20 h (20H) of anoxic 
      submergence in liver and skeletal muscle of T. scripta elegans with a particular 
      focus on regulatory changes in the phosphorylation states of targets. The data 
      showed that phosphorylation of multiple mTOR targets was suppressed in skeletal 
      muscle, but activated in the liver. Phosphorylated mTOR(Ser2448) showed no change 
      in skeletal muscle but had increased by approximately 4.5-fold in the liver after 
      20H of anoxia. The phosphorylation states of upstream positive regulators of mTOR 
      (p-PDK-1(Ser241), p-AKT(Ser473), and protein levels of GbetaL), the relative levels 
      of dephosphorylated active PTEN, as well as phosphorylation state of negative 
      regulators (TSC2(Thr1462), p-PRAS40(Thr246)) were generally found to be 
      differentially regulated in skeletal muscle and in liver. Downstream targets of 
      mTOR (p-p70 S6K(Thr389), p-S6(Ser235), PABP, p-4E-BP1(Thr37/46), and 
      p-eIF4E(Ser209)) were generally unchanged in skeletal muscle but upregulated in 
      most targets in liver. These findings indicate that protein synthesis is enhanced 
      in the liver and suggests an increase in the synthesis of crucial proteins 
      required for anoxic survival.
FAU - Szereszewski, Kama E
AU  - Szereszewski KE
AD  - Institute of Biochemistry and Department of Biology, Carleton University, 1125 
      Colonel By Drive, Ottawa, Ontario, K1S 5B6, Canada.
FAU - Storey, Kenneth B
AU  - Storey KB
AUID- ORCID: 0000-0002-2280-7599
AD  - Institute of Biochemistry and Department of Biology, Carleton University, 1125 
      Colonel By Drive, Ottawa, Ontario, K1S 5B6, Canada. kenneth.storey@carleton.ca.
LA  - eng
GR  - 6793/Natural Sciences and Engineering Research Council of Canada/
PT  - Journal Article
DEP - 20171214
PL  - Netherlands
TA  - Mol Cell Biochem
JT  - Molecular and cellular biochemistry
JID - 0364456
RN  - EC 2.7.11.1 (TOR Serine-Threonine Kinases)
RN  - S88TT14065 (Oxygen)
SB  - IM
MH  - *Adaptation, Physiological
MH  - Animals
MH  - Energy Metabolism
MH  - *Gene Expression Regulation
MH  - Hypoxia/metabolism/physiopathology/*veterinary
MH  - Liver/metabolism
MH  - Muscle, Skeletal/metabolism
MH  - Oxygen/metabolism
MH  - Phosphorylation
MH  - *Protein Biosynthesis
MH  - Signal Transduction
MH  - TOR Serine-Threonine Kinases/*metabolism
MH  - Turtles/metabolism/*physiology
MH  - Up-Regulation
OTO - NOTNLM
OT  - AKT
OT  - Anoxia
OT  - Metabolic rate depression
OT  - Protein synthesis
OT  - Red-eared slider
OT  - S6
EDAT- 2017/12/16 06:00
MHDA- 2018/09/18 06:00
CRDT- 2017/12/16 06:00
PHST- 2017/08/28 00:00 [received]
PHST- 2017/12/08 00:00 [accepted]
PHST- 2017/12/16 06:00 [pubmed]
PHST- 2018/09/18 06:00 [medline]
PHST- 2017/12/16 06:00 [entrez]
AID - 10.1007/s11010-017-3247-y [pii]
AID - 10.1007/s11010-017-3247-y [doi]
PST - ppublish
SO  - Mol Cell Biochem. 2018 Aug;445(1-2):13-23. doi: 10.1007/s11010-017-3247-y. Epub 
      2017 Dec 14.