The association between increasing levels of O -GlcNAc and galectins in the liver tissue of hibernating thirteen-lined ground squirrels ( Ictidomys tridecemlineatus )

AbstractPost-translational glycosylation of proteins withO-linked β-N-acetylglucosamine (O-GlcNAcylation) and changes of galectin expression profiles are essential in many cellular stress responses. We examine this regulation in the liver tissue of hibernating thirteen-lined ground squirrels (Ictidomys tridecemlineatus) representing a biological model of hypometabolism and physiological stress resistance. The tissue levels ofO-GlcNAcylated proteins as well as galectin-1 and galectin-3 proteins detected by immunodot blot assay were significantly lower by 4.6 –5.4-, 2.2–2.3- and 2.5–2.9-fold, respectively, in the non-hibernating summer squirrels compared with those in winter, whether hibernating or aroused. However, there were no differences in the expression of genes encoding enzymes involved inO-GlcNAc cycle (O-GlcNAc transferase andO-GlcNAcase) and such galectins asLGALS1,LGALS2,LGALS3,LGALS4 andLGALS9. Only the expression ofLGALS8 gene in the liver tissue was significantly decreased by 37.6  ± 0.1% in hibernating ground squirrels relative to summer animals. Considering that the expression of a proven genetic biomarkerELOVL6 encoding ELOVL fatty acid elongase 6 was readily upregulated in non-hibernating animals by 11.3 –32.9-fold, marginal differential changes in the expression of galectin genes cannot be classified as biomarkers of hibernation. Thus, this study provides evidence that hibernation inIctidomys tridecemlineatus is associated with increasingO-GlcNA...
Source: Cell and Tissue Research - Category: Cytology Source Type: research