MAPT and amyotrophic lateral sclerosis: We did not observe significant expression changes of other genes linked with ALS or FTLD such as Tarbdp, Grn, Ubqnl2, Vcp, Mapt, Sod1 or Optn. TLS-/- mice also showed upregulation of Xlr4b and Xlr3b (Figure 4b and Additional file 1: Figure S4a, Online Resource), two related genes implicated in neuronal or behavioral functions [24,25].