In this context, it is noteworthy that conditional knockout of the proteasome subunit Rpt3 in motor neurons in mice results in motor neuron degeneration and locomotor defects accompanied by the accumulation of a number of ALS-related proteins, including TDP-43, FUS and optineurin in intraneuronal inclusions (Tashiro et al., 2012). Here, FUS is linked to amyotrophic lateral sclerosis.