Format

Send to

Choose Destination
  • Showing results for activation of the unfolded protein response during anoxia exposure in the turtle trachemys scripta elegans. Your search for Activation of the unfolded protein response during anoxia exposure in the turtle Trachemys scripta elegan retrieved no results.
Mol Cell Biochem. 2013 Feb;374(1-2):91-103. doi: 10.1007/s11010-012-1508-3. Epub 2012 Nov 3.

Activation of the unfolded protein response during anoxia exposure in the turtle Trachemys scripta elegans.

Author information

1
Department of Biology, Institute of Biochemistry, Carleton University, 1125 Colonel By Drive, Ottawa, ON, K1S 5B6, Canada. krivoruchko@gmail.com

Abstract

Red-eared slider turtles, Trachemys scripta elegans, can survive for several weeks without oxygen when submerged in cold water. We hypothesized that anaerobiosis is aided by adaptive up-regulation of the unfolded protein response (UPR), a stress-responsive pathway that is activated by accumulation of unfolded proteins in the endoplasmic reticulum (ER) and functions to restore ER homeostasis. RT-PCR, western immunoblotting and DNA-binding assays were used to quantify the responses and/or activation status of UPR-responsive genes and proteins in turtle tissues after animal exposure to 5 or 20 h of anoxic submergence at 4 °C. The phosphorylation state of protein kinase-like ER kinase (PERK) (a UPR-regulated kinase) and eukaryotic initiation factor 2 (eIF2α) increased by 1.43-2.50 fold in response to anoxia in turtle heart, kidney, and liver. Activation of the PERK-regulated transcription factor, activating transcription factor 4 (ATF4), during anoxia was documented by elevated atf4 transcripts and total ATF4 protein (1.60-2.43 fold), increased nuclear ATF4 content, and increased DNA-binding activity (1.44-2.32 fold). ATF3 and GADD34 (downstream targets of ATF4) also increased by 1.38-3.32 fold in heart and liver under anoxia, and atf3 transcripts were also elevated in heart. Two characteristic chaperones of the UPR, GRP78, and GRP94, also responded positively to anoxia with strong increases in both the transcript and protein levels. The data demonstrate that the UPR is activated in turtle heart, kidney, and liver in response to anoxia, suggesting that this pathway mediates an integrated stress response to protect tissues during oxygen deprivation.

PMID:
23124854
DOI:
10.1007/s11010-012-1508-3
[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Springer
Loading ...
Support Center