Description
Description: This assay employs a two-site sandwich ELISA to quantitate HBXIP in samples. An antibody specific for HBXIP has been pre-coated onto a microplate. Standards and samples are pipetted into the wells and any HBXIP present is bound by the immobilized antibody. After removing any unbound substances, a biotin-conjugated antibody specific for HBXIP is added to the wells. After washing, Streptavidin conjugated Horseradish Peroxidase (HRP) is added to the wells. Following a wash to remove any unbound avidin-enzyme reagent, a substrate solution is added to the wells and color develops in proportion to the amount of HBXIP bound in the initial step. The color development is stopped and the intensity of the color is measured.
Overview: HBXIP encodes a protein that specifically complexes with the C-terminus of hepatitis B virus X protein (HBx). The function of this protein is to negatively regulate HBx activity and thus to alter the replication life cycle of the virus.
The deduced 91-amino acid protein has a calculated molecular mass of 9.6 kD. It contains a putative leucine zipper motif and may form an amphipathic helix. HBXIP also has 2 putative threonine phosphorylation sites. Northern blot analysis detected a 0.7-kb transcript in all tissues tested, with highest expression in skeletal and cardiac muscle.HBXIP expression in differentiated hepatocellular carcinoma cells reduced wildtype HBV replication to levels observed following infection with an HBX-minus virus