D uncompacted myelin (G) have been sometimes observed in mutant nerves. H, I, Improved myelin thickness at P45 in Dlg1 fl/fl P0Cre nerves. J, J’, Occasional myelin outfoldings in Dlg1 fl/fl P0Cre nerves. Scale bars: A , 1 m; H ‘, 2 m.expression in mutant nerve lysates may be explained by the truth that the nerve also consists of perineurial cells, which express Dlg1 (Fig. 1B). We analyzed sciatic nerves of Dlg1 fl/fl P0cre mice starting at P10. Electron microscopy evaluation revealed increased myelin thickness in mutant nerve fibers (Fig. 2A ). Additional, myelin outfoldings, polyaxonal myelination, and fibers with uncompacted myelin had been occasionally observed (Fig. 2E ). Along with occasional myelin outfoldings, hypermyelinated fibers15298 J.GLUT1-IN-2 Membrane Transporter/Ion Channel Neurosci., September 18, 2013 33(38):15295Noseda et al. DDIT4/REDD1/RTP801 Is Novel Regulator of PNS MyelinationFigure three. Transient hypermyelination in conditional Dlg1 fl/fl P0Cre nerves. A, Quantification of the g ratio as a function of axonal diameter in Dlg1 fl/fl P0Cre sciatic nerves and controls at P20 shows elevated myelin thickness in mutant nerves (Dlg1 fl/fl P0Cre, 0.664 0.013; WT, 0.703 0.002, p 0.037 on indicates, n 1500 fibers, n 3 animals per genotype). B, Axonal diameter distribution at P20. C, Quantification with the g ratio as a function of axonal diameter in Dlg1 fl/fl P0Cre sciatic nerves and controls at P90 (Dlg1 fl/fl P0Cre, 0.674 0.034; WT, 0.670 0.035; p 0.475 on indicates, n 1600 fibers, n four animals per genotype). D, Axonal diameter distribution at P90. E, Quantification in the g ratio as a function of axonal diameter in Dlg1 fl/ P0Cre sciatic nerves and handle sciatic nerves at P90 (Dlg1 fl/ P0Cre, 0.689 0.003; WT, 0.682 0.01; p 0.55 on suggests, n 3000 fibers, n five animals per genotype). F, Axonal diameter distribution at P90. G, Quantification with the g ratio as a function of axonal diameter in Dlg1 fl/fl P0Cre sciatic nerves and control sciatic nerves at six months (Dlg1 fl/fl P0Cre, 0.693 0.019; WT, 0.680 0.019; p 0.61 on means, n 1500 fibers, n three animals per genotype). H, Axonal diameter distribution at 6 months. C, E, G, All show standard myelin thickness in mutant nerves.HAPSBC manufacturer All data represent means SEM.PMID:23664186 had been also evident at P20 and P45 (Fig. 2H ‘). The enhance of myelin thickness in mutant nerves was additional assessed by morphometric analysis (Fig. three). The imply g-ratio worth of mutant nerve fibers at P20 was drastically reduce compared with wildtype nerves, hence confirming hypermyelination in Dlg1 fl/fl P0Cre nerves (Fig. 3A,B). Enhanced Krox20 (at P10 and P20) and P0 myelin protein expression (at P20) in mutant nerves further supported enhanced myelination (Fig. four A, B; data not shown). Lastly, the amount of myelinated fibers at P1 two was equivalent amongst mutant and wild-type sciatic nerves as assessed by bothimmunohistochemistry and morphological evaluation (data not shown). DLG1 is believed to potentiate PTEN phospholipid phosphatase activity toward PIP3, therefore negatively modulating the PI3K/ AKT signaling pathway (Cotter et al., 2010). Although PTEN expression levels have been similar involving mutant and handle nerves at P10 (data not shown), P20, and P60 (Fig. 4D), AKT phosphorylation at S473 was improved in Dlg1 fl/fl P0Cre nerves at P10 but not at P20, suggesting that the hypermyelinating signal is temporary (Fig. 4C; data not shown).Noseda et al. DDIT4/REDD1/RTP801 Is Novel Regulator of PNS MyelinationJ. Neurosci., September 18, 2013 33(38):152955305 DDIT4/REDD1/RTP801 expression is upr.
