Alternatively spliced focal adhesion kinase in rat brain with increased autophosphorylation activity
Alternatively spliced focal adhesion kinase in rat brain with increased autophosphorylation activity
复制标题
DOI：
10.1074/jbc.272.45.28720
复制
发表时间：
1997-11-07
影响因子：
4.8
通讯作者：
Girault, JA
中科院分区：
文献类型：
--
作者：
Burgaya, F;Toutant, M;Girault, JA
pp 125粘着斑激酶（FAK）是一种由整合素结合和G蛋白偶联受体启动的细胞质酪氨酸激酶，在脑组织中高表达。脑组织中的FAK mRNA具有较高的分子量和较高的自磷酸化活性。大鼠纹状体FAK mRNA除了在3 ′端编码区插入9个碱基外，还含有几个额外的短外显子，分别编码28、6和7个氨基酸残基的肽段（称为框28、6和7），围绕自磷酸化的Tyr-397。在转染的COS 7细胞中，框6和7的存在赋予增加的整体酪氨酸磷酸化，用磷酸化状态特异性抗体评估的Tyr-397的更高磷酸化，以及免疫沉淀物中更活跃的自磷酸化。框28的存在没有进一步改变这些参数，海马FAK的二维磷酸肽图与FAR+的那些相同6，7。各种外显子的存在并不改变FAK与c-Src、n-Src或Fyn的相互作用。因此，FAK的几种剪接异构体优先在大鼠脑中表达，其中一些具有增加的自磷酸化活性，这表明FAR可能在神经元中具有特定的性质。
pp125 focal adhesion kinase (FAK), a cytoplasmic tyrosine kinase transducing signals initiated by integrin engagement and G protein-coupled receptors, is highly expressed in brain. FAR from brain had a higher molecular weight and an increased autophosphorylation activity, than from other tissues, In addition to a 9-base insertion in the 3'-coding region, which defines FAK(+), rat striatal FAK mRNAs contained several additional short exons, coding for peptides of 28, 6, and 7 residues, respectively (termed boxes 28, 6, and 7), surrounding the autophosphorylated Tyr-397. In transfected COS 7 cells, the presence of boxes 6 and 7 conferred an increased overall tyrosine phosphorylation, a higher phosphorylation of Tyr-397 assessed with a phosphorylation state-specific antibody, and a more active autophosphorylation in immune precipitates. The presence of box 28 did not alter further these parameters, Two-dimensional phosphopeptide maps of hippocampal FAK were identical to those of FAR+6,7. The presence of the various exons did not alter the interaction of FAK with c-Src, n-Src; or Fyn. Thus, several splice isoforms of FAK are preferentially expressed in rat brain, some of which have an increased autophosphorylation activity, suggesting that FAR may have specific properties in neurons.