HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Supplemental Tables All Versions of this Article: 295/1/R316    most recent 00418.2007v1 Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Google Scholar Articles by Martin, S. L. Articles by Carey, H. V. PubMed PubMed Citation Articles by Martin, S. L. Articles by Carey, H. V.

COMPARATIVE AND EVOLUTIONARY PHYSIOLOGY

Proteomic analysis of the winter-protected phenotype of hibernating ground squirrel intestine

¹Department of Cell and Developmental Biology and ²Program in Molecular Biology, University of Colorado School of Medicine, Aurora, Colorado; and ³Department of Comparative Biosciences, University of Wisconsin School of Veterinary Medicine, and ⁴Departments of Statistics and of Botany, University of Wisconsin, Madison, Wisconsin

Submitted 14 June 2007 ; accepted in final form 19 April 2008

The intestine of hibernating ground squirrels is protected against damage by ischemia-reperfusion (I/R) injury. This resistance does not depend on the low body temperature of torpor; rather, it is exhibited during natural interbout arousals that periodically return hibernating animals to euthermia. Here we use fluorescence two-dimensional difference gel electrophoresis (DIGE) to identify protein spot differences in intestines of 13-lined ground squirrels in the sensitive and protected phases of the circannual hibernation cycle, comparing sham-treated control animals with those exposed to I/R. Protein spot differences distinguished the sham-treated summer and hibernating samples, as well as the response to I/R between summer and hibernating intestines. The majority of protein changes among these groups were attributed to a seasonal difference between summer and winter hibernators. Many of the protein spots that differed were unambiguously identified by high-pressure liquid chromatography followed by tandem mass spectrometry of their constituent peptides. Western blot analysis confirmed significant upregulation for three of the proteins, albumin, apolipoprotein A-I, and ubiquitin hydrolase L1, that were identified in the DIGE analysis as increased in sham-treated hibernating squirrels compared with sham-treated summer squirrels. This study identifies several candidate proteins that may contribute to hibernation-induced protection of the gut during natural torpor-arousal cycles and experimental I/R injury. It also reveals the importance of enterocyte maturation in defining the hibernating gut proteome and the role of changing cell populations for the differences between sham and I/R-treated summer animals.

13-lined ground squirrel; ischemia-reperfusion; mucosa; Spermophilus tridecemlineatus