Anti-VAPA Antibody Picoband® Fluoro550 Conjugated

VAMP-Associated Protein A (or Vesicle-Associated Membrane Protein-Associated Protein A) is a protein that in humans is encoded by the VAPA gene. The protein encoded by this gene is a type IV membrane protein. It is present in the plasma membrane and intracellular vesicles. It may also be associated with the cytoskeleton. This protein may function in vesicle trafficking, membrane fusion, protein complex assembly and cell motility. Alternative splicing occurs at this locus and two transcript variants encoding distinct isoforms have been identified.

A synthetic peptide corresponding to a sequence at the N-terminus of human VAPA, which shares 94.1% amino acid (aa) sequence identity with mouse and rat VAPA.

Overexpressed in hepatomas and colonic tumors. Also expressed in skeletal muscle, brain, heart, placenta, lung, liver, kidney and pancreas. Expression is elevated in the brain; highly expressed in the Purkinje cell bodies of the cerebellum.

Binds to the plus end of microtubules and regulates microtubule dynamics and microtubule organization. Acts as processive microtubule polymerase. Promotes cytoplasmic microtubule nucleation and elongation. Plays a major role in organizing spindle poles. In spindle formation protects kinetochore microtubules from depolymerization by KIF2C and has an essential role in centrosomal microtubule assembly independently of KIF2C activity. Contributes to centrosome integrity. Acts as component of the TACC3/ch-TOG/clathrin complex proposed to contribute to stabilization of kinetochore fibers of the mitotic spindle by acting as inter-microtubule bridge. The TACC3/ch-TOG/clathrin complex is required for the maintenance of kinetochore fiber tension. Enhances the strength of NDC80 complex-mediated kinetochore-tip microtubule attachments.

1. Nishimura, Y., Hayashi, M., Inada, H., Tanaka, T. Molecular cloning and characterization of mammalian homologues of vesicle-associated membrane protein-associated (VAMP-associated) proteins. Biochem. Biophys. Res. Commun. 254: 21-26, 1999. 2. Weir, M. L., Klip, A., Trimble, W. S. Identification of a human homologue of the vesicle-associated membrane protein (VAMP) -associated protein of 33 kDa (VAP-33) : a broadly expressed protein that binds to VAMP. Biochem. J. 333: 247-251, 1998.