VAPB, also known as vesicle-associated membrane protein (VAMP)-associated protein B, is a type IV transmembrane protein and member of the VAP family of proteins. This protein may play a role in vesicle trafficking. It is found in plasma and intracellular vesicle membranes as a homodimer and heterodimer with VAPA, and interacts with VAMP1 and VAMP2. Defects in VAPB are a cause of amyotrophic lateral sclerosis type 8 and spinal muscular atrophy autosomal dominant Finkel type. Recombinant human VAPB protein, fused to His-tag at N-terminus, was expressed in E.coli and purified by using conventional chromatography.