Recombinant Human HLA-DQA1(24-220 aa) fused with His tag at N-terminal was expressed in E. coli.
HLA-DQA1 belongs to the HLA class II alpha chain paralogues. The class II molecule is a heterodimer consisting of an alpha (DQA) and a beta chain (DQB), both anchored in the membrane. It plays a central role in the immune system by presenting peptides derived from extracellular proteins. Class II molecules are expressed in antigen presenting cells (APC: B Lymphocytes, dendritic cells, macrophages). The alpha chain is approximately 33-35 kDa. It is encoded by 5 exons; exon 1 encodes the leader peptide, exons 2 and 3 encode the two extracellular domains, and exon 4 encodes the transmembrane domain and the cytoplasmic tail. Within the DQ molecule both the alpha chain and the beta chain contain the polymorphisms specifying the peptide binding specificities, resulting in up to four different molecules. Typing for these polymorphisms is routinely done for bone marrow transplantation.
1M PBS (58 mM Na2HPO4, 17 mM NaH2PO4, 68 mM NaCl, pH8.0 ), added with 300 mM Imidazole and 0.7% sarcosyl, 15% glycerol.
EDIVADHVASYGVNLYQSYGPSGQYTHEFDGDEQFYVDLGRKETVWCLPVLRQFRFDPQFALTNIAVLKHNLNSL IKRSNSTAATNEVPEVTVFSKSPVTLGQPNILICLVDNIFPPVVNITWLSNGHSVTEGVSETSFLSKSDHSFFKI SYLTLLPSAEESYDCKVEHWGLDKPLLKHWEPEIPAPMSELTETVVC
Aliquot and store at -20 centigrade to -80 centigrade for up to 6 months. Avoid freeze thaw cycles.