The VAP-B is an integral endoplasmic reticulum (ER)-membrane protein implicated in the regulation of a wide range of cellular processes, including membrane trafficking, lipid transport and metabolism, and the unfolded protein response. In 2004, a dominant missense mutation (P56S) within the human VAP-Bgene was identified in a wide spectrum of adult motor neuron diseases (MNDs), including familial amyotrophic lateral sclerosis (fALS) (ALS8) and spinal muscular atrophy.
