CUL2 and amyotrophic lateral sclerosis: von Hippel-Lindau protein (VHL) promotes the degradation of fragmented TDP-43 at proteasomes with a ubiquitin ligase, cullin-2 (CUL2), and colocalizes with TDP-43 aggregates in oligodendrocytes in postmortem ALS spinal cords, implying that imbalances in VHL and CUL2 may underlie oligodendrocyte dysfunction in ALS [173].