Fig. 5: Deletion of Phb1 in SCs triggers a mitochondrial stress response.
From: Prohibitin 1 is essential to preserve mitochondria and myelin integrity in Schwann cells
a p-eIF2α is upregulated in sciatic nerve lysates of PHB1-SCKO mice (red) compared to controls (blue), indicating activation of the ISR. N = 6–7 animals per genotype. Unpaired two-tailed t-test. p-eIF2α [P20 (t = 3.068, df = 10, p = 0.013), P40 (t = 4.948, df = 10, p = 0.0019), P90 (t = 6.088, df = 12, p = 0.0029)]; eIF2α [P20 (t = 0.759, df = 10, p = 0.091), P40 (t = 4.532, df = 10, p = 0.023), P90 (t = 3.582, df = 12, p = 0.018)]. b Representative western blot for CLPP, a protease involved in the UPRmt response (left) and quantification of relative expression levels at different time points (right). N = 6-10 animals per genotype. Unpaired two-tailed t-test [P20 (t = 1.616, df = 18, p = 0.12), P40 (t = 1.416, df = 10, p = 0.19), P90 (t = 0.696, df = 12, p = 0.5)]. c Representative immunoblot for HSPD1, a chaperone participating in the UPRmt cascade (left) and quantification of relative expression levels at different time points (right). N = 4–5 animals per genotype. Unpaired two-tailed t-test [P20 (t = 1.46, df = 6, p = 0.19), P40 (t = 0.057, df = 8, p = 0.96), P90 (t = 1.46, df = 10, p = 0.17)]. d RT-qPCR analysis of gene expression of Clpp, Hspd1 and Hspe1 (Hsp10). N = 4–5 animals per genotype. Unpaired two-tailed t-test Clpp [P20 (t = 1.013, df = 7, p = 0.34), P40 (t = 2.642, df = 7, p = 0.033)]; Hspd1 [P20 (t = 0.217, df = 7, p = 0.83), P40 (t = 0.9, df = 7, p = 0.4)]; Hspe1 [P20 (t = 0.899, df = 7, p = 0.4), P40 (t = 1.472, df = 7, p = 0.18)]. e The mitochondrial stress response involves ATF4, as suggested by the upregulation of its targets: Asgn (aspargine synthetase), Chac1 (cation transport regulator-like protein 1), Pck2 (phosphoenolpyruvate carboxykinase 2), Dddit3 (DNA damage-inducible transcript 3), Psph (phosphoserine phosphatase). N = 4–5 animals per genotype. Unpaired two-tailed t-test. Atf4 [P20 (t = 0.456, df = 7, p = 0.66), P40 (t = 0.288, df = 7, p = 0.78)]; Asns [P20 (t = 12.772, df = 7, p = 0.00095), P40 (t = 5.459, df = 7, 0.000004)]; Chac1 [P20 (t = 8.361, df = 7, 0.000069), P40 (t = 7.134, df = 7, p = 0.00019)]; Pck2 [P20 (t = 6.84, df = 7, p = 0.00024), P40 (t = 5.897, df = 7, p = 0.0006)]; Psph [P20 (t = 0.051, df = 7, p = 0.96), P40 (t = 1.79, df = 7, p = 0.12)]; Ddit3 [P20 (t = 2.292, df = 7, p = 0.056), P40 (t = 5.113, df = 7, p = 0.0014)]. Data are presented as mean ± SEM. *p < 0.05, **p < 0.01, ***p < 0.001. n.s. non-significant.
