Recombinant Human HA-GABARAP Vinyl Sulfone Protein, CF Summary

Product Datasheets

Carrier Free

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.

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.

Background: GABARAP

gamma -Aminobutyric Acid Receptor-associated Protein (GABARAP), also known as Apg8p1, is 117 amino acid (aa) protein with a predicted molecular weight of 14 kDa. It is a member of the GABARAP subfamily of the Autophagy-related 8 (Atg8) family of proteins (1). The GABARAP subfamily also includes GABARAPL1. GABARAP/Apg8p1 has 100% aa sequence identity with its mouse and rat orthologs and is orthologous to yeast Atg8. Atg8 family members show structural similarity with Ubiquitin, but lack aa sequence similarity. GABARAP/Apg8p1 was first described for its putative involvement GABA A Receptor trafficking (2,3). However, it is best known for its role in autophagy (1,4). GABARAP/Apg8p1 covalently attaches to phosphatidylethanolamine (PE) in the phagophore (autophagosome precursor) membrane using a Ubiquitin-like conjugation system that includes Ubiquitin-activating (E1)-, Ubiquitin-conjugating (E2)-, and Ubiquitin Ligase (E3)-like enzymes. Here it is involved in the later stages of autophagosome maturation (4,5). It may also be involved in cargo recruitment to autophagosomes (1).

This N-terminal HA-tagged protein is a potent, irreversible and specific inhibitor of Agp8-specific isopeptidases (such as Apg84B, Cat # E-400). Apg84B activities include the processing of Apg8 precursor proteins and the removal of Apg8 proteins that are conjugated to phosphatidylethanolamine during autophagy. These processes can be inhibited by this vinyl sulfone derivative which reacts with the Apg84B active site cysteine. The HA peptide sequence (YPYDVPDYA) is derived from the influenza hemagglutinin protein. This epitope allows for the sensitive identification or purification of such deconjugating activities since it is specifically recognized by anti-HA antibodies and/or anti-HA-agarose.

Related Research Areas

• Autophagy
• GABA Receptors
• Neurotransmitter Receptors on VSMC
• Ubiquitin-like Modifiers (UBLs) and Regulators