Circadian rhythmicity of the GC-KLF15-BCAA axis is dysregulated in severe SMA mice. a. Corticosterone levels in serum of post-natal day (P) 2 and P7 Smn−/−;SMN2 mice compared to healthy control littermates at the Zeitgeber time (ZT) 5 and ZT17. Data represent mean ± SD; n = 3–4 animals per group, two-way ANOVA; *p < 0.05 b. qPCR analysis of diurnal expression of GRα mRNA in the tibialis anterior (TA) of P2 and P7 Smn−/−;SMN2 mice compared to healthy controls. c. qPCR analysis of diurnal expression of GRβ mRNA in the TA of P2 and P7 Smn−/−;SMN2 mice compared to healthy controls. d. qPCR analysis of diurnal expression of Klf15 mRNA in the TA of P2 and P7 Smn−/−;SMN2 mice compared to healthy controls. b-d: Data represent mean ± SD; n = 3–5 animals per group, two-way ANOVA; *p < 0.05, **p < 0.01, ****p < 0.0001; # indicates cycling ZT1 data is duplicated. e. Levels of the BCAAs valine, leucine and isoleucine in triceps of P2 and P7 Smn−/−;SMN2 and healthy controls. f. Levels of the BCAAs in serum of P2 and P7 Smn−/−;SMN2 and healthy control animals. e–f: each data point represents the pooling of 5–15 animals.