REGULATION OF B-CELL ANTIGEN RECEPTOR SIGNAL TRANSDUCTION AND PHOSPHORYLATION BY CD45
REGULATION OF B-CELL ANTIGEN RECEPTOR SIGNAL TRANSDUCTION AND PHOSPHORYLATION BY CD45
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DOI：
10.1126/science.1648262
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发表时间：
1991-06-28
期刊：
影响因子：
56.9
通讯作者：
CAMBIER, JC
中科院分区：
文献类型：
--
作者：
JUSTEMENT, LB;CAMPBELL, KS;CAMBIER, JC
CD45 是具有磷酸酪氨酸磷酸酶活性的膜蛋白家族的成员，并且是淋巴细胞中大部分酪氨酸磷酸酶活性的来源。鉴于其酶活性和高拷贝数，CD45 似乎可能在淋巴细胞受体的跨膜信号转导中发挥作用，而淋巴细胞受体与酪氨酸激酶的激活相关。研究发现，只有当细胞表达 CD45 时，B 细胞抗原受体才能转导 Ca2+ 动员信号。此外，膜免疫球蛋白 M (mIgM) 和 CD45 从用 CD45 抗体处理的细胞表面丢失，表明这些蛋白质之间存在物理相互作用。最后，CD45 使 mIg 相关蛋白复合物去磷酸化，该复合物似乎在抗原受体的信号转导中发挥作用。这些数据表明CD45作为与抗原受体相关的蛋白质复合物的组成部分出现，并且CD45可以通过调节抗原受体亚基的磷酸化状态来调节信号转导。
CD45 is a member of a family of membrane proteins that possess phosphotyrosine phosphatase activity, and is the source of much of the tyrosine phosphatase activity in lymphocytes. In view of its enzymatic activity and high copy number, it seems likely that CD45 functions in transmembrane signal transduction by lymphocyte receptors that arc coupled to activation of tyrosine kinases. The B cell antigen receptor was found to transduce a Ca2+-mobilizing signal only if cells expressed CD45. Also, both membrane immunoglobulin M (mIgM) and CD45 were lost from the surface of cells treated with antibody to CD45, suggesting a physical interaction between these proteins. Finally, CD45 dephosphorylated a complex of mIg-associated proteins that appears to function in signal transduction by the antigen receptor. These data indicate that CD45 occurs as a component of a complex of proteins associated with the antigen receptor, and that CD45 may regulate signal transduction by modulating the phosphorylation state of the antigen receptor subunits.