Some of the tyrosine residues can be tagged with a phosphate group (phosphorylated) by protein kinases. (In its phosphorylated state, it is referred to as phosphotyrosine.). Tyrosine phosphorylation is considered as one of the key steps in signal transduction and regulation of enzymatic activity. The advent of anti-phospho-tyrosine antibodies is one of significant events in signal transduction research. Before the availability of anti-phosphotyrosine antibodies, tyrosyl phospyhorylation of proteins and enzymes was investigated through hazardous and time-consuming radioactive experiments. Anti-phosphotyrosine antibodies are commonly used in western blots after the targeted proteins have been immunoprecipitated to measure the tyrosyl phosphorylation of the proteins. Anti-phosphotyrosine antibodies are also directly used on cell lysate to examine the overall change of tyrosine phosphorylation level in reponse to various treatments.，官网链接：https://www.sigmaaldrich.cn/product/mm/16199 默克 科研、开发、生产。 作为生命科学行业的全球领先供应商，我们致力于为科研、生物技术开发和生产，以及制药药物疗法开发和生产提供各类解决方案和服务。

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