Substrate specificity of R3 receptor-like protein tyrosine phosphatase subfamily towards receptor protein tyrosine kinases
Substrate specificity of R3 receptor-like protein tyrosine phosphatase subfamily towards receptor protein tyrosine kinases
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R3受体样蛋白酪氨酸磷酸酶亚家族对受体蛋白酪氨酸激酶的底物特异性
DOI：
10.1074/jbc.m113.458489
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发表时间：
2013
期刊：
影响因子：
--
通讯作者：
Noda M
中科院分区：
文献类型：
--
作者：
Sakuraba J;Shintani T;Tani S;Noda M
受体样蛋白酪氨酸磷酸酶（RPTP）参与细胞功能的各个方面，如增殖、分化、存活、迁移和代谢。少数RPTP已被报道可调节包括受体蛋白酪氨酸激酶（RPTKs）在内的一些细胞蛋白的活性。然而，我们对RPTPs在RPTKs调控中的作用的理解仍然有限。据报道，R3 RPTP亚家族在包括血管和神经系统在内的几种组织的发育中起关键作用。在这里，我们研究了4个R3 RPTP亚家族成员和21个RPTK成员之间的酶-底物关系，从14个RPTK亚家族中选择使用哺乳动物双杂交系统与底物捕获RPTP突变体。在84个RPTP-RPTK组合中，我们检测到30个正相互作用：25个酶-底物关系是新的。我们随机选择了几个RPTKs假定为R3 RPTPs的底物，并验证了这个屏幕的结果通过在体外去磷酸化试验，并通过基于细胞的分析，涉及过表达和敲低实验。由于无一例外地验证了它们的功能关系，因此确定为潜在底物的RPTK实际上可能是R3 RPTP的生理底物。有趣的是，一些RPTK被所有R3成员识别为底物，但其他RPTK仅被一个或几个成员识别。本研究中确定的酶-底物关系将揭示R3 RPTP亚家族的生理作用。背景：我们对受体样蛋白酪氨酸磷酸酶（RPTP）和受体蛋白酪氨酸激酶（RPTK）之间的生理相关性的理解是有限的。结果：多种RPTK被鉴定为R3 RPTP亚家族的底物。结论：R3亚家族的成员表现出类似的，但不同的特异性对RPTKs.Significance：这项研究揭示了R3 RPTP亚家族的生理作用。
Receptor-like protein-tyrosine phosphatases (RPTPs) are involved in various aspects of cellular functions, such as proliferation, differentiation, survival, migration, and metabolism. A small number of RPTPs have been reported to regulate activities of some cellular proteins including receptor protein-tyrosine kinases (RPTKs). However, our understanding about the roles of individual RPTPs in the regulation of RPTKs is still limited. The R3 RPTP subfamily reportedly plays pivotal roles in the development of several tissues including the vascular and nervous systems. Here, we examined enzyme-substrate relationships between the four R3 RPTP subfamily members and 21 RPTK members selected from 14 RPTK subfamilies by using a mammalian two-hybrid system with substrate-trapping RPTP mutants. Among the 84 RPTP-RPTK combinations conceivable, we detected 30 positive interactions: 25 of the enzyme-substrate relationships were novel. We randomly chose several RPTKs assumed to be substrates for R3 RPTPs, and validated the results of this screen byin vitrodephosphorylation assays, and by cell-based assays involving overexpression and knock-down experiments. Because their functional relationships were verified without exception, it is probable that the RPTKs identified as potential substrates are actually physiological substrates for the R3 RPTPs. Interestingly, some RPTKs were recognized as substrates by all R3 members, but others were recognized by only one or a few members. The enzyme-substrate relationships identified in the present study will shed light on physiological roles of the R3 RPTP subfamily.Background: Our understanding of the physiological relevance between receptor-like protein-tyrosine phosphatase (RPTP) and receptor protein-tyrosine kinase (RPTK) is limited.Results: Multiple RPTKs were identified as substrates for the R3 RPTP subfamily.Conclusion: Members of the R3 subfamily show a similar but distinct specificity toward RPTKs.Significance: This study sheds light on physiological roles of the R3 RPTP subfamily.