Structure and expression of the mb‐1 transcript in human lymphoid cells-猫眼课题宝

人淋巴细胞中mb-1转录物的结构和表达

DOI：

发表时间：

1992

期刊：

Clinical and Experimental Immunology

影响因子：

4.6

通讯作者：

中科院分区：

医学3区

文献类型：

作者：

I. Leduc;J. Preud’homme;M. Cogné

mb-1基因编码一种与膜结合免疫球蛋白（mlg）相关的蛋白质，并已表明它可能在信号转导中发挥作用。使用鼠探针，我们克隆了与鼠mb-1序列同源的人互补DNA。其完整序列与最近发表的人类cDNA序列完全一致，但与先前报道的部分序列不同。我们研究了不同成熟阶段的人类细胞中的MB-1表达。在携带μ、γ、α1或α2同种型mlg的B细胞系中可检测到大量的单个1-4 kb转录物。mb-1 mRNA也在prc-B细胞和表达缺少相关轻链的截短膜fi链的细胞中表达。在含有大量浆细胞的组织样品中仅发现痕量的ol 'mb-1 mRNA，而在几种浆细胞瘤细胞系中没有发现mRNA，表明浆细胞中的表达被关闭。在T细胞或非淋巴组织中未发现信号。总之，这些结果表明，无论mlg重链的同种型如何，人mb-1基因在prc-B细胞和B淋巴细胞中表达，并且不再在浆细胞中表达。

The mb‐1 gene encodes a protein associated with membrane‐bound immunoglobulins (mlg) and it has been suggested that it may play a role in signal iransduction. Using a murine probe, we cloned a human complementary DNA homologous to the murine mb‐1 sequence. Its complete sequence is in full agreement with a recently published human cDNA sequence but differs from a previously reported partial sequence. We studied mb‐1 expression in human cells at various maturation stages. Large amounts of a single 1–4 kb transcript were detectable in B cell lines carrying mlg of the μ, γ, α1 or α2 isotype. The mb‐1 mRNA was also expressed in prc‐B cells and in cells expressing truncated membrane fi chains devoid of associated light chains. Only trace amounts ol 'mb‐1 mRNA were found in tissue samples containing numerous plasma cells, while no mRNA was delected in several plasmacytoma cell lines, indicating that expression is shut down in plasma cells. No signal was found in T cells or in non‐lymphoid tissues. Altogether, these results show that the human mb‐1 gene is expressed in prc‐B cells and B lymphocytes, regardless of the isotype of the mlg heavy chain and is no longer expressed in plasma cells.