Mitogen-activated protein kinases and anoxia tolerance in turtles
The response of two vertebrate mitogen-activated protein kinase (MAPK) family members, the extracellular signal-regulated kinases (ERKs) and c-Jun NH2-terminal kinases (JNKs), to anoxia exposure in vivo was examined in organs (liver, heart, kidney, brain, spleen) of the anoxia-tolerant adult turtle, Trachemys scripta elegans. ERKs activities rose during anoxia only in spleen (a 2.8-fold increase). JNK activity showed a significant increase only in liver (4-fold increase) after 5 hr of anoxic submergence but declined thereafter. Levels of the transcription factor c-Fos were strongly suppressed in liver, heart, and kidney of anoxia-exposed turtles, whereas levels increased 2-fold in anoxic brain. The effect of anoxia on c-Myc was organ-specific and variable with 2- and 1.5-fold increases in protein expression in kidney and brain, respectively, and a 60% decrease in anoxic spleen. These results for an anoxia-tolerant animal suggest the potential importance of the MAPKs and of the immediate-early genes (c-fos, c-myc) in mediating adaptive responses to oxygen deprivation. (C) 2000 Wiley-Liss, Inc.
|Journal||Journal of Experimental Zoology|
Greenway, S.C. (Steven C.), & Storey, K. (2000). Mitogen-activated protein kinases and anoxia tolerance in turtles. Journal of Experimental Zoology, 287(7), 477–484. doi:10.1002/1097-010X(20001201)287:7<477::AID-JEZ3>3.0.CO;2-4