Anti-VAPB (Vesicle-associated Membrane Protein-associated Protein B/C, VAMP-B/VAMP-C, VAMP-associate

Vesicle-associated membrane protein associated protein B is an~30kD ubiquitously expressed type IV transmembrane protein belonging to the VAP family. It is found in endoplasmic reticulum (ER), Golgi and other membranes as a homodimer or a heterodimer with VAP-A, probably associating through a GxxxG motif in the transmembrane regions. Human VAP-B cDNA encodes 243aa that include a 222aa cytoplasmic domain and a 21aa C-terminal membrane anchor. The cytoplasmic domain contains a mobile sperm protein (MSP) domain aa7-124 and a coiled-coil region aa159-196. Human VAP-B shares 90%, 89%, 96%, 96% and 94% aa identity with mouse, rat, canine, bovine and porcine VAP-B, respectively. VAP-A and VAP-B MSP domains recruit FFAT motif-containing proteins to the cytosolic surface of ER membranes. FFAT proteins mediate many of the effects of VAPs on regulation of membrane transport, phospholipid biosynthesis, microtubule organization, and the unfolded protein response. A human polymorphism of VAP-B, P56S, is found in three familial motor neuron diseases, notably the amylotrophic lateral sclerosis variant ALS8. It produces a non-functional protein that can dimerize with and inhibit function of normal VAP-B, leading formation of intracellular aggregates and increased ER-stress-induced death of motor neurons. It can also promote cleavage and secretion of soluble VAP-B, which can then function as a ligand for EPH receptors. A naturally occurring 99aa isoform of VAP-B that diverges at 71aa within the MSP domain is termed VAP-C. Applications: Suitable for use in Immunohistochemistry. Other applications not tested. Recommended Dilutions: Immunohistochemistry: 8-25ug/ml using immersion fixed paraffin-embedded sections of human brain (cerebellum), Optimal dilutions to be determined by the researcher. Storage and Stability: Lyophilized powder may be stored at -20°C. Stable for 12 months after receipt at -20°C. Reconstitute with sterile PBS. Aliquot to avoid repeated freezing and thawing. Store at -20°C. Reconstituted product is stable for 12 months at -20°C. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap. Further dilutions can be made in assay buffer.