β2微球蛋白

1A1M, 1A1N, 1A1O, 1A6Z, 1A9B, 1A9E, 1AGB, 1AGC, 1AGD, 1AGE, 1AGF, 1AKJ, 1AO7, 1B0G, 1B0R, 1BD2, 1C16, 1CE6, 1CG9, 1DE4, 1DUY, 1DUZ, 1E27, 1E28, 1EEY, 1EEZ, 1EFX, 1EXU, 1GZP, 1GZQ, 1HHG, 1HHH, 1HHI, 1HHJ, 1HHK, 1HLA, 1HSA, 1HSB, 1I1F, 1I1Y, 1I4F, 1I7R, 1I7T, 1I7U, 1IM3, 1IM9, 1JF1, 1JGD, 1JGE, 1JHT, 1JNJ, 1K5N, 1KPR, 1KTL, 1LDS, 1LP9, 1M05, 1M6O, 1MHE, 1MI5, 1N2R, 1OF2, 1OGA, 1OGT, 1ONQ, 1P7Q, 1PY4, 1Q94, 1QEW, 1QLF, 1QQD, 1QR1, 1QRN, 1QSE, 1QSF, 1QVO, 1R3H, 1S9W, 1S9X, 1S9Y, 1SYS, 1SYV, 1TMC, 1TVB, 1TVH, 1UQS, 1UXS, 1UXW, 1VGK, 1W0V, 1W0W, 1W72, 1X7Q, 1XH3, 1XR8, 1XR9, 1XZ0, 1YDP, 1YPZ, 1ZHK, 1ZHL, 1ZS8, 1ZSD, 1ZT4, 1ZVS, 2A83, 2AK4, 2AV1, 2AV7, 2AXF, 2AXG, 2BCK, 2BNQ, 2BNR, 2BSR, 2BSS, 2BST, 2BVO, 2BVP, 2BVQ, 2C7U, 2CII, 2CIK, 2CLR, 2D31, 2D4D, 2D4F, 2DYP, 2E8D, 2ESV, 2F53, 2F54, 2F74, 2F8O, 2FYY, 2FZ3, 2GIT, 2GJ6, 2GT9, 2GTW, 2GTZ, 2GUO, 2H26, 2H6P, 2HJK, 2HJL, 2HLA, 2HN7, 2J8U, 2JCC, 2NW3, 2NX5, 2P5E, 2P5W, 2PO6, 2PYE, 2RFX, 2UWE, 2V2W, 2V2X, 2VB5, 2VLJ, 2VLK, 2VLL, 2VLR, 2X4N, 2X4O, 2X4P, 2X4R, 2X4S, 2X4T, 2X4U, 2X70, 2X89, 2XKS, 2XKU, 2XPG, 2YPK, 2YPL, 2YXF, 2Z9T, 3AM8, 3B3I, 3B6S, 3BGM, 3BH8, 3BH9, 3BHB, 3BO8, 3BP4, 3BP7, 3BVN, 3BW9, 3BWA, 3BXN, 3BZE, 3BZF, 3C9N, 3CDG, 3CII, 3CIQ, 3CZF, 3D18, 3D25, 3D2U, 3D39, 3D3V, 3DBX, 3DHJ, 3DHM, 3DTX, 3DX6, 3DX7, 3DX8, 3DXA, 3EKC, 3FFC, 3FQN, 3FQR, 3FQT, 3FQU, 3FQW, 3FQX, 3FT2, 3FT3, 3FT4, 3GIV, 3GJF, 3GSN, 3GSO, 3GSQ, 3GSR, 3GSU, 3GSV, 3GSW, 3GSX, 3H7B, 3H9H, 3H9S, 3HAE, 3HCV, 3HG1, 3HLA, 3HPJ, 3HUJ, 3I6G, 3I6K, 3I6L, 3IB4, 3IXA, 3JTS, 3KLA, 3KPL, 3KPM, 3KPN, 3KPO, 3KPP, 3KPQ, 3KPR, 3KPS, 3KWW, 3KXF, 3KYN, 3KYO, 3L3D, 3L3G, 3L3I, 3L3J, 3L3K, 3LKN, 3LKO, 3LKP, 3LKQ, 3LKR, 3LKS, 3LN4, 3LN5, 3LOW, 3LOZ, 3LV3, 3M17, 3M1B, 3MGO, 3MGT, 3MR9, 3MRB, 3MRC, 3MRD, 3MRE, 3MRF, 3MRG, 3MRH, 3MRI, 3MRJ, 3MRK, 3MRL, 3MRM, 3MRN, 3MRO, 3MRP, 3MRQ, 3MRR, 3MV7, 3MV8, 3MV9, 3MYJ, 3MYZ, 3MZT, 3NA4, 3NFN, 3O3A, 3O3B, 3O3D, 3O3E, 3O4L, 3OV6, 3OX8, 3OXR, 3OXS, 3PWJ, 3PWL, 3PWN, 3PWP, 3QDA, 3QDG, 3QDJ, 3QDM, 3QEQ, 3QFD, 3QFJ, 3QZW, 3REW, 3RL1, 3RL2, 3RWJ, 3S6C, 3SDX, 3SJV, 3SKM, 3SKO, 3SPV, 3T8X, 3TID, 3TIE, 3TLR, 3TM6, 3TO2, 3TZV, 3U0P, 3UPR, 3UTQ, 3UTS, 3UTT, 3V5D, 3V5H, 3V5K, 3VCL, 3VFM, 3VFS, 3VFU, 3VFV, 3VFW, 3VH8, 3VRI, 3VRJ, 3VWJ, 3VWK, 3VXM, 3VXN, 3VXO, 3VXP, 3VXR, 3VXS, 3VXU, 3W0W, 3W39, 4E0K, 4E0L, 4E5X, 4EN3, 4EUP, 4EUQ, 4F7M, 4F7P, 4F7T, 4FTV, 4FXL, 4G8G, 4G8I, 4G9D, 4G9F, 4GKN, 4GKS, 4GUP, 4HKJ, 4HWZ, 4HX1, 4I48, 4I4W, 4JFD, 4JFE, 4JFF, 4JFO, 4JFP, 4JFQ, 4JQX, 4JRX, 4JRY, 4K71, 4K7F, 4KDT, 4L4T, 4L4V, 4LCW, 4LHU, 4MNQ· extracellular region · extracellular space · endoplasmic reticulum lumen · plasma membrane · external side of plasma membrane · ER to Golgi transport vesicle membrane · phagocytic vesicle membrane · early endosome membrane · early endosome lumen· response to molecule of bacterial origin · antigen processing and presentation of peptide antigen via MHC class I · antigen processing and presentation of exogenous peptide antigen via MHC class I, TAP-dependent · antigen processing and presentation of exogenous peptide antigen via MHC class I, TAP-independent · antigen processing and presentation of exogenous protein antigen via MHC class Ib, TAP-dependent · viral reproduction · cytokine-mediated signaling pathway · T cell differentiation in thymus · protein refolding · response to drug · antigen processing and presentation of exogenous peptide antigen via MHC class I · innate immune response · response to cadmium ion · regulation of defense response to virus by virus · regulation of immune responseβ2微球蛋白（英语：β2-microglobulin，缩写B2M）是MHC1类分子分子的组成部分之一，在所有有核的细胞中（即不包括红细胞）都有表达。在人类基因组中，β2微球蛋白由B2M 基因所编码。β2-微球蛋白位于细胞表面的α3链旁，但与α链不同的是，β2并没有跨膜区域，且为非共价结合。在β2的“上方”（指远离细胞膜的一端）为α链的α1区和α2区，构成了MHC的肽结合区。β2微球蛋白不止参与形成第一类MHC分子，还能组成与之类似的表面受体，如CD1和Qa（英语：Alloantigen）等。β2微球蛋白还有一个功能，就是能与HFE蛋白（英语：HFE (gene)）结合，来调控铁调素在肝脏中的表达。铁调素会与肠上皮细胞和巨噬细胞膜上的膜铁转运蛋白（英语：ferroportin）作用。可以降低食物中和红血球回收的铁质摄取，该功能的丧失会导致铁过量和血色沉着病。