IgJ Protein, Human, Recombinant (His Tag)

Immunoglobulin J chain, also known as IGJ and IGCJ, is a secreted polypeptide which is the first immunoglobulin-related polypeptide expressed during the embryogenesis and differentiation of B cells in the fetal liver. The joining Immunoglobulin J chain is a small polypeptide, expressed by mucosal and glandular plasma cells, which regulates polymer formation of immunoglobulin (Ig) A and IgM. Immunoglobulin J chain / IGJ serves to link two monomer units of either IgM or IgA. In the case of IgM, the J chain-joined dimer is a nucleating unit for the IgM pentamer, and in the case of IgA, it induces larger polymers. Immunoglobulin J chain / IGJ also helps to bind these immunoglobulins to the secretory component. J-chain incorporation into polymeric IgA (pIgA, mainly dimers) and pentameric IgM endows these antibodies with several salient features. Immunoglobulin J chain / IGJ is involved in creating the binding site for pIgR / SC in the Ig polymers, not only by determining the polymeric quaternary structure but also by interacting directly with the receptor protein. Both the immunoglobulin J chain / IGJ and the pIgR/SC are key proteins in secretory immunity.

A DNA sequence encoding the mature form of human IGJ (NP_653247.1) (Gln 23-Asp 159) was fused with a polyhistidine tag at the C-terminus and a pelB singnal peptide at the N-terminus.

At Leading Biology, the biological activity of a recombinant protein is routinely measured using a bioassay, e.g. chemotaxis or cell proliferation assay, enzyme assay, or a functional ELISA. When a recombinant protein is an enzyme, specific activity is derived from an enzymatic assay. Each enzyme is tested for potency by cleavage of a substrate. We are in the process of updating the biological activity data. If you have any questions regarding this update, please feel free to contact our technical support team.

Lyophilized from sterile PBS, pH 8.0 Please contact us for any concerns or special requirements. Normally 5 % - 8 % trehalose, mannitol and 0.01% Tween 80 are added as protectants before lyophilization. Please refer to the specific buffer information in the hard copy of CoA.

The recombinant human IGJ comprises 147 amino acids and has a predicted molecular mass of 17 kDa. It migrates as an approximately 26 kDa band in SDS-PAGE under reducing conditions.

In general, recombinant proteins are provided as lyophilized powder which are shipped at ambient temperature. Bulk packages of recombinant proteins are provided as frozen liquid. They are shipped out with blue ice unless customers require otherwise. Stable for 1 year at -20°C or below from date of shipment. For maximum recovery of product, centrifuge the original vial after thawing and opening the cap. For long-term storage, aliquot and store at -20°C or below. Avoid repeated freeze-thaw cycles.