Fig. 5

Smn, Tweak, and Fn14 depletion impact each other’s expression. a–b qPCR analysis of parvalbumin, Tweak, Fn14, Pgc-1α, Mef2d, Glut-4, HKII, Klf15, and Smn in triceps muscle from postnatal day (P) 7 Tweak^−/− (a) and Fn14^−/− (b) mice. Normalized relative expressions for each gene are compared to WT. Data are mean ± SEM, n = 4 animals per experimental group, two-way ANOVA, uncorrected Fisher’s LSD, ns, not significant, *p < 0.05, ***p < 0.001, ****p < 0.0001. c–j qPCR analysis of Smn (c), Tweak (d), Fn14 (e), Pgc-1α (f), Mef2d (g), Glut-4 (h), HKII (i), and Klf15 (j) in siRNA-mediated Tweak-, Fn14-, and Smn-depleted and control proliferating (day 0) and differentiated (day 7) C2C12 cells. Normalized relative expressions for day 1 experimental groups are compared to day 1 untreated group, and normalized relative expressions for day 7 experimental groups are compared to day 7 untreated group. Data are mean ± SEM, n = 3 per experimental group, two-way ANOVA, Dunnett’s multiple comparisons test, *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001. k Proposed model of the relationship between Smn and the Tweak/Fn14 signaling pathway. Red lines represent inhibition, and blue lines represent activation