CD19 OF B-CELLS AS A SURROGATE KINASE INSERT REGION TO BIND PHOSPHATIDYLINOSITOL 3-KINASE
CD19 OF B-CELLS AS A SURROGATE KINASE INSERT REGION TO BIND PHOSPHATIDYLINOSITOL 3-KINASE
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DOI：
10.1126/science.7684160
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发表时间：
1993-05-14
期刊：
影响因子：
56.9
通讯作者：
FEARON, DT
中科院分区：
文献类型：
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作者：
TUVESON, DA;CARTER, RH;FEARON, DT
B和T淋巴细胞上的抗原受体通过激活非受体蛋白酪氨酸激酶（PTK）来传递信号。一个受体PTK家族包含具有序列酪氨酸-X-X-甲硫氨酸（其中X是任何氨基酸）的激酶插入区，当磷酸化时，其介导磷脂酰肌醇3-激酶（PI 3-激酶）的结合和活化。B细胞的CD 19膜蛋白通过膜免疫球蛋白M（mIgM）增强活化，并且发现其含有激酶插入区的功能类似物。mIgM的连接诱导CD 19的磷酸化并与PI 3-激酶结合。因此，CD 19作为mIgM的替代激酶插入区，通过提供非受体PTK激活PI 3-激酶的手段。
Antigen receptors on B and T lymphocytes transduce signals by activating nonreceptor protein tyrosine kinases (PTKs). A family of receptor PTKs contains kinase insert regions with the sequence tyrosine-X-X-methionine (where X is any amino acid) that when phosphorylated mediate the binding and activation of phosphatidylinositol 3-kinase (PI 3-kinase). The CD19 membrane protein of B cells enhances activation through membrane immunoglobulin M (mIgM) and was found to contain a functional analog of the kinase insert region. Ligation of mIgM induced phosphorylation of CD19 and association with PI 3-kinase. Thus, CD19 serves as a surrogate kinase insert region for mIgM by providing the means for PI 3-kinase activation by nonreceptor PTKs.