ROLE OF BETA-2-MICROGLOBULIN IN THE INTRACELLULAR PROCESSING OF HLA ANTIGENS
ROLE OF BETA-2-MICROGLOBULIN IN THE INTRACELLULAR PROCESSING OF HLA ANTIGENS
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DOI：
10.1021/bi00519a003
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发表时间：
1981-01-01
期刊：
影响因子：
2.9
通讯作者：
PETERSON, PA
中科院分区：
文献类型：
--
作者：
SEGE, K;RASK, L;PETERSON, PA
在2个Daudi和Raji淋巴母细胞样细胞系中检测HLA-A、-B和-C抗原的生物合成。在Raji细胞中，HLA-A、-B和-C抗原H链在内质网中变成核心糖基化的，如它们对内切-H消化和衣霉素处理的敏感性所证明的。β 2-微球蛋白过量存在于Raji细胞的内质网中，并在H链合成时与H链缔合。脉冲追踪实验表明，Raji HLA-A、-B和-C抗原H链变成末端糖基化的，因为它们改变的特性包括对endo-H消化的抗性、对神经氨酸酶处理的敏感性和岩藻糖的掺入。Daudi HLA-A、-B和-C抗原H链正常合成，并变为核心糖基化，但未末端糖基化。其他糖基化的细胞表面蛋白，如HLA-DR抗原，在Daudi细胞中显示正常的糖基化。末端糖基化HLA-A、-B和-C抗原H链的缺失可能不是Daudi细胞生物合成机制中的一般缺陷的结果。Daudi细胞缺乏合成β 2-微球蛋白的能力，β 2-微球蛋白是所有HLA-A、-B和-C抗原的共同亚基。因此，β 2-微球蛋白对于新合成的HLA-A、-B和-C抗原的细胞内转运可能是重要的。
The biosynthesis of HLA-A, -B and -C antigens was examined in the 2 Daudi and Raji lymphoblastoid cell lines. In Raji cells the HLA-A, -B and -C antigen H chains become core-glycosylated in the endoplasmic reticulum as evidenced by their sensitivity to endo-H digestion and tunicamycin treatment. .beta.2-Microglobulin is present in excess in the endoplasmic reticulum of the Raji cells and associates with the H chain at the time of synthesis of the H chain. Pulse-chase experiments demonstrated that the Raji HLA-A, -B and -C antigen H chains become terminally glycosylated since their changed characteristics included resistance to endo-H digestion, sensitivity to neuraminidase treatment and incorporation of fucose. Daudi HLA-A, -B and -C antigen H chains are synthesized normally and become core-glycosylated but not terminally glycosylated. Other glycosylated cell surface proteins, like the HLA-DR antigens, display normal glycosylation in Daudi cells. The absence of terminally glycosylated HLA-A, -B and -C antigen H chains is probably not the result of a general defect in the biosynthetic machinery of Daudi cells. Daudi cells lack the ability to synthesize .beta.2-microglobulin, the common subunit of all HLA-A, -B and -C antigens. Thus, .beta.2-microglobulin may be of importance for the intracellular transport of newly synthesized HLA-A, -B and -C antigens.