Recombinant Human VAP-A Protein, CF

Catalog # Availability Size / Price Qty
R&D Systems Recombinant Proteins and Enzymes
1 Image
Product Details
Supplemental Products

Recombinant Human VAP-A Protein, CF Summary

Product Specifications

>95%, by SDS-PAGE under reducing conditions and visualized by silver stain
Endotoxin Level
<0.10 EU per 1 μg of the protein by the LAL method.
Measured by its binding ability in a functional ELISA. When rmEphB2/Fc Chimera (Catalog # 467-B2) is coated at 2 μg/mL (100 μL/well), the concentration of rhVAP-A that produces 50% of the optimal binding response is found to be approximately 0.8‑4 μg/mL.
E. coli-derived human VAP-A protein
Met1-Met132, with a C-terminal 6-His tag
Accession #
N-terminal Sequence
Structure / Form
Predicted Molecular Mass
15.5 kDa
16 kDa, reducing conditions

Product Datasheets

You must select a language.



Carrier Free

What does CF mean?

CF stands for Carrier Free (CF). We typically add Bovine Serum Albumin (BSA) as a carrier protein to our recombinant proteins. Adding a carrier protein enhances protein stability, increases shelf-life, and allows the recombinant protein to be stored at a more dilute concentration. The carrier free version does not contain BSA.

What formulation is right for me?

In general, we advise purchasing the recombinant protein with BSA for use in cell or tissue culture, or as an ELISA standard. In contrast, the carrier free protein is recommended for applications, in which the presence of BSA could interfere.


Formulation Lyophilized from a 0.2 μm filtered solution in MOPS and NaCl.
Reconstitution Reconstitute at 100 μg/mL in PBS.
Shipping The product is shipped at ambient temperature. Upon receipt, store it immediately at the temperature recommended below.
Stability & Storage: Use a manual defrost freezer and avoid repeated freeze-thaw cycles.
  • 12 months from date of receipt, -20 to -70 °C as supplied.
  • 1 month, 2 to 8 °C under sterile conditions after reconstitution.
  • 3 months, -20 to -70 °C under sterile conditions after reconstitution.
Reconstitution Calculator

Reconstitution Calculator

The reconstitution calculator allows you to quickly calculate the volume of a reagent to reconstitute your vial. Simply enter the mass of reagent and the target concentration and the calculator will determine the rest.


Background: VAP-A

Vesicle-associated membrane protein (VAMP)‑associated protein A (VAP‑A; also VAMP‑A and VAP-33) is a 33 kDa, ubiquitously expressed, type IV transmembrane protein belonging to the VAP family of proteins (1). It is found in plasma and ER membranes as well as in intracellular vesicles as a homodimer and a heterodimer with VAP-B. Human VAP-A is synthesized as a 249 amino acid (aa) precursor that contains a 227 aa cytoplasmic domain and a 21 aa transmembrane region. The cytoplasmic domain contains a mobile sperm protein (MSP) domain (aa 14 ‑ 131) and a coiled-coil region (aa 169 ‑ 205). Human VAP-A is 97% aa identical to mouse and rat VAP-A. VAP-A and VAP-B recruit FFAT (two phenylalanines in an acidic tract)-motif-containing proteins to the cytosolic surface of ER membranes through a conserved region within their MSP domain, and they have been implicated in regulation of membrane transport, phospholipid biosynthesis, and the unfolded protein response (2 ‑ 3). Their role in maintaining the identities of intracellular organelles has not been demonstrated, but their ability to interact with lipid-transfer/binding proteins (LT/BPs) may affect the lipid composition of certain cellular membranes (2, 4). One study shows that VAPs play a critical role in maintaining the structural and functional properties of the Golgi complex (2). Researchers found that knockdown of VAP reduces the levels of phosphatidylinositol-4-phosphate (PI4P), diacylglycerol (DAG), and sphingomyelin (SM) in Golgi membranes and exports pleiotropic effects in Golgi-mediated transport (2). The effects of VAPs are mediated by their interacting FFAT-motif-containing proteins Nir2, OSBP, and CERT (2). VAPs provide a scaffold for these LT/BPs at the ER-Golgi membrane contact sites, thereby affecting the lipid composition of the Golgi membranes and consequently their structural and functional identities (2). Most recently, researchers found that VAP-A associates and co‑localizes with protrudin, a protein that promotes neurite formation, and found that it was an important regulator both of the subcellular localization of protrudin and of its ability to stimulate neurite outgrowth (5).

  1. Weir, M.L. et al. (1998) Biochem. J. 333:247.
  2. Peretti, D. et al. (2008) Mol. Biol. Cell 19:3871.
  3. Kaiser, S.E. et al. (2005) Structure 13:1035.
  4. Loewen, C.J. et al. (2003) EMBO J. 22:2025.
  5. Saita, S. et al. (2009) J. Biol. Chem. 284:13766.
    Long Name
    VAMP [Vesicle-associated Membrane Protein]-associated Protein A
    Entrez Gene IDs
    9218 (Human); 30960 (Mouse); 58857 (Rat)
    Alternate Names
    hVAP-33; MGC3745,33 kDa VAMP-associated protein; VAMP (vesicle-associated membrane protein)-associated protein A, 33kDa; VAMP-A; VAP-33; VAP33VAMP (vesicle-associated membrane protein)-associated protein A (33kD); VAPA; VAP-A; VAP-AVAMP-associated protein A; vesicle-associated membrane protein-associated protein A


    No product specific FAQs exist for this product, however you may

    View all Proteins and Enzyme FAQs

    Recombinant Proteins

    Reconstitution Buffers

    Reviews for Recombinant Human VAP-A Protein, CF

    There are currently no reviews for this product. Be the first to review Recombinant Human VAP-A Protein, CF and earn rewards!

    Have you used Recombinant Human VAP-A Protein, CF?

    Submit a review and receive an Amazon gift card.

    $25/€18/£15/$25CAN/¥75 Yuan/¥1250 Yen for a review with an image

    $10/€7/£6/$10 CAD/¥70 Yuan/¥1110 Yen for a review without an image

    Submit a Review