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Title: Feeding during hibernation shifts gene expression toward active season levels in brown bears (Ursus arctos)
Hibernation in bears involves a suite of metabolical and physiological changes, including the onset of insulin resistance, that are driven in part by sweeping changes in gene expression in multiple tissues. Feeding bears glucose during hibernation partially restores active season physiological phenotypes, including partial resensitization to insulin, but the molecular mechanisms underlying this transition remain poorly understood. Here, we analyze tissue-level gene expression in adipose, liver, and muscle to identify genes that respond to midhibernation glucose feeding and thus potentially drive postfeeding metabolical and physiological shifts. We show that midhibernation feeding stimulates differential expression in all analyzed tissues of hibernating bears and that a subset of these genes responds specifically by shifting expression toward levels typical of the active season. Inferences of upstream regulatory molecules potentially driving these postfeeding responses implicate peroxisome proliferator-activated receptor gamma (PPARG) and other known regulators of insulin sensitivity, providing new insight into high-level regulatory mechanisms involved in shifting metabolic phenotypes between hibernation and active states.  more » « less
Award ID(s):
2138649
PAR ID:
10469444
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
American Physiological Society
Date Published:
Journal Name:
Physiological genomics
Volume:
55
Issue:
9
ISSN:
1531-2267
Subject(s) / Keyword(s):
differential isoform usage gene expression hibernation insulin resistance PPAR signaling
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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