SEQUENCE OF THE LYB-2 B-CELL DIFFERENTIATION ANTIGEN DEFINES A GENE SUPERFAMILY OF RECEPTORS WITH INVERTED MEMBRANE ORIENTATION
SEQUENCE OF THE LYB-2 B-CELL DIFFERENTIATION ANTIGEN DEFINES A GENE SUPERFAMILY OF RECEPTORS WITH INVERTED MEMBRANE ORIENTATION
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DOI：
10.1073/pnas.86.4.1352
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发表时间：
1989-02-01
影响因子：
11.1
通讯作者：
PARNES, JR
中科院分区：
文献类型：
--
作者：
NAKAYAMA, E;VONHOEGEN, I;PARNES, JR
Lyb-2 是一种小鼠 B 细胞分化抗原，在前 B 细胞和 B 细胞表面表达，但在终末分化的抗体分泌浆细胞上不表达。 Lyb-2 已被证明在 B 细胞活化和分化中发挥作用，并且可能是 B 细胞生长因子或淋巴因子的受体。我们分离并测序了编码 Lyb-2.1 等位基因的 cDNA。 Lyb-2 mRNA 仅在 B 系细胞中表达，在抗体分泌细胞系中不表达。预测的蛋白质含有 354 个氨基酸，并且缺乏氨基末端信号肽。该蛋白质的羧基末端位于细胞外部。序列比较表明，Lyb-2 与脱唾液酸糖蛋白受体和 CD23（IgE 的 B 细胞特异性 Fc 受体）同源，两者的羧基末端均位于细胞外部。因此，这些分子构成了具有反向膜方向的细胞表面受体的基因超家族。
Lyb-2 is a mouse B-cel differentiation antigen expressed on the surface of pre-B cells and B cells but not on terminally differentiated antibody-secreting plasma cells. Lyb-2 has been shown to play a role in B-cell activation and differentiation and may be a receptor for a B-cell growth factor or lymphokine. We have isolated and sequenced cDNA encoding the Lyb-2.1 allele. Lyb-2 mRNA is expressed only in B-lineage cells and is absent from antibody-secreting cell lines. The predicted protein contains 354 amino acids and is lacking an amino-terminal signal peptide. The protein is shown to be oriented with its carboxyl terminus external to the cell. Sequence comparisons demonstrate that Lyb-2 is homologous to the asialoglycoprotein receptor and to CD23, the B-cell-specific Fc receptor for IgE, both of which are oriented with their carboxyl termini external to the cell. These molecules, therefore, constitute a gene superfamily of cell surface receptors with inverted membrane orientation.