Hemizygous deletion of Tbk1 worsens neuromuscular junction pathology in TDP-43G298S transgenic mice.

Hemizygous deletion of Tbk1 worsens neuromuscular junction pathology in TDP-43G298S transgenic mice. Exp Neurol. 2020 Oct 07;:113496 Authors: Sieverding K, Ulmer J, Bruno C, Satoh T, Tsao W, Freischmidt A, Akira S, Wong PC, Ludolph AC, Danzer KM, Lobsiger CS, Brenner D, Weishaupt JH Abstract Mutations in the genes TARDBP (encoding the TDP-43 protein) and TBK1 can cause familial ALS. Neuronal cytoplasmatic accumulations of the misfolded, hyperphosphorylated RNA-binding protein TDP-43 are the pathological hallmark of most ALS cases and have been suggested to be a key aspect of ALS pathogenesis. Pharmacological induction of autophagy has been shown to reduce mutant TDP-43 aggregates and alleviate motor deficits in mice. TBK1 is exemplary for several other ALS genes that regulate autophagy. Consequently, we employed double mutant mice with both a heterozygous Tbk1 deletion and transgenic expression of human TDP-43G298S to test the hypothesis that impaired autophagy reduces intracellular clearance of an aggregation-prone protein and enhances toxicity of mutant TDP-43. The heterozygous deletion of Tbk1 did not change expression or cellular distribution of TDP-43 protein, motor neuron loss or reactive gliosis in the spinal cord of double-mutant mice at the age of 19 months. However, it aggravated muscle denervation and, albeit to a small and variable degree, motor dysfunction in TDP-43G298S transgenic mice, as similarly observed in the SO...
Source: Experimental Neurology - Category: Neurology Authors: Tags: Exp Neurol Source Type: research