RMDN3 and amyotrophic lateral sclerosis: In CV1 and NSC34 motor neuron cells, the amyotrophic lateral sclerosis (ALS)-related vesicle-associated membrane protein-associated protein-B (VAPB) has been found to interact with PTPIP51 at the mitochondria-ER junction; downregulation of both proteins impairs mitochondrial Ca2+ uptake and the mutated VAPB-P56S is enriched in MAMs fraction in ALS patients and causes mitochondrial transportation disruption and Ca2+ overload24, 25, 26.