Reduced Soluble Ubiquilin2 in Amyotrophic Lateral Sclerosis Carrying Ubiquilin2 (P494L) Mutation: Clinicopathological and Biochemical Evidence From an Autopsy Case

We report the clinicopathological and biochemical findings of ALS associated with a UBQLN2 P494L mutation. Autopsy revealed widespread TDP-43 pathology and UBQLN2-positive inclusions. Immunoblot analysis demonstrated a marked reduction of soluble UBQLN2, supporting functional UBQLN2 insufficiency as a pathogenic mechanism underlying TDP-43 aggregation.