This Mouse Beta-2 microglobulin overexpression lysate was created in HEK293 Cells and intented for use as a Western blot (WB) positive control. Purification of Beta-2 microglobulin protein (Cat: 50957-M08H) from the overexpression lysate was verified.
A DNA sequence encoding the mouse B2M (P01887) (Met 1-Met 119), without the propeptide, was fused with a C-terminal polyhistidine tag.
The secreted recombinant mouse B2M comprises 110 amino acids and has a calculated molecular mass of 13 kDa. The apparent molecular mass of rmB2M is approximately 15 kDa in SDS-PAGE under reducing conditions.
Cell lysate was prepared by homogenization of the over-expressed cells in ice-cold modified RIPA Lysis Buffer with cocktail of protease inhibitors (Sigma). Cell debris was removed by centrifugation. Protein concentration was determined by Bradford assay (Bio-Rad protein assay, Microplate Standard assay). The cell lysate was boiled for 5 min in 1 x SDS loading buffer (50 mM Tris-HCl pH 6.8, 12.5% glycerol, 1% sodium dodecylsulfate, 0.01% bromophenol blue) containing 5% b-mercaptoethanol, and lyophilized.
B2M, also known as β2-Microglobulin or CDABP0092, is a component of MHC class I molecules found expression in all nucleated cells (excludes red blood cells). The major function of MHC class I moleculesis is to display fragments of proteins from within the cell to T-cells and cells containing foreign proteins will be attacked. B2M (β2-Microglobulin) is a low molecular weight protein. It was demonstrated that B2M (β2-Microglobulin) was localized in the membranes of nucleated cells and was found to be associated with HL-A antigens. B2M (β2- Microglobulin) is present in free form in various body fluids and as a subunit of histocompatibility antigens on cell surfaces lateral to the α3 chain. Unlike α3, β2 has no transmembrane region. Directly above β2 lies the α1 chain, which itself is lateral to the α2. In the absence of B2M (β2 microglobulin), very limited amounts of MHC class I (classical and non-classical) molecules can be detected on the surface. In the absence of MHC class I, CD8 T cells, a subset of T cells involved in the development of acquired immunity cannot develop. Low levels of B2M (β2 microglobulin) can indicate non-progression of HIV.
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