Research Paper Volume 11, Issue 18 pp 7587—7604

Attenuated activation of the unfolded protein response following exercise in skeletal muscle of older adults

Figure 2. Pathway analysis of the unfolded protein response mRNA transcripts post-exercise. The unfolded protein response (UPR) in skeletal muscle volcano plots of mRNA expressed as a log fold change from baseline to 18h post-exercise in young (A) and older (B) adults. The x-axis represents the log fold change, while y-axis represents the –log FDR-value for each gene. Dotted vertical lines represent the threshold for statistical significance (FDR < 0.05, −log [FDR value] > 1.303). Gene set enrichment analysis (GSEA) was performed using Broad’s GSEA software for 72 genes related to UPR pathway and revealed a significantly greater upregulation of the UPR pathway between rest and 18h post-exercise in young (C) compared to older (D) adults (FDR < 0.05 and an absolute log2 fold change ≥ 0.5). (E) UPR up- and down-regulated mRNAs significantly altered (FDR < 0.05 and an absolute fold change of ≥ 1.2) between baseline and 18h post-exercise in young and older adults, sorted by the log2 fold change. NS = not significantly altered.