Fig. 4

Activation of the UPR and downstream translational attenuation in IBM. a XBP1 transcript levels (RNA-seq). b Isoform-specific expression of ubiquitous (U) and spliced (S) XBP1 transcript (RNA-seq). c Representative immunoblots of UPR effector molecules d Quantification of UPR effector protein levels. e Relative phosphorylation of eIF2α, a marker of translational attenuation. Graphed data expressed as mean + SEM. N of 5, 4, and 7 for non-myositis controls (CON), DM, and IBM, respectively; *P < 0.05 vs CON; ^† P < 0.05 vs DM