Regulation of the Nuclear Factor of Activated T Cell (NFAT) Family of Transcription Factors in the Freeze Tolerant Wood Frog, Rana sylvatica

During winter, wood frogs (Rana sylvatica) can endure whole body freezing with 65-70% of total body water converted to extracellular ice. As a result, cells experience extensive dehydration when water exits as well as anoxia due to interruption of blood flow. Adapting to such challenges requires metabolic rearrangement, partially mediated by transcription factor control over gene expression. Here, involvement of the nuclear factor of activated T-cells (NFAT) transcription factors, isoforms c1-c4, was analyzed in liver and skeletal muscle over freeze/thaw and anoxia/re-oxygenation cycles. Freezing activated NFATc3 in liver, leading to increased osteopontin expression and glycogen synthase kinase 3β repression (the latter potentially linked with glucose production as a cryoprotectant). Anoxia activated NFATc4 in liver, leading to increased atrial natriuretic peptide levels. Neither freezing nor anoxia significantly affected NFATs in skeletal muscle. Overall, the study indicates that NFATs have a crucial role to play in the natural cryoprotection of liver.

Name thesis:degree_name

Master of Science (M.Sc.)

Level thesis:degree_level

Master's

Discipline thesis:degree_discipline

Biology

Grantor dc:publisher

Carleton University

Year dc:date.issued

2016

Author dc:creator

• Al-Attar, Rasha

Statement dc:rights

• Copyright © 2016 the author(s). Theses may be used for non-commercial research, educational, or related academic purposes only. Such uses include personal study, research, scholarship, and teaching. Theses may only be shared by linking to Carleton University Institutional Repository and no part may be used without proper attribution to the author. No part may be used for commercial purposes directly or indirectly via a for-profit platform; no adaptation or derivative works are permitted without consent from the copyright owner.

Language dc:language.iso

en

DOI

10.22215/etd/2016-11700

OAI identifier oai:identifier

oai:carleton.scholaris.ca:20.500.14718/39163