Despite significant interest in therapeutic targeting of splicing, few chemical probes are available for the proteins involved in splicing. Here, we show that elaborated stereoisomeric acrylamide EV96 and its analogues lead to a selective T cell state-dependent loss of interleukin 2-inducible T cell kinase (ITK) by targeting one of the core splicing factors SF3B1. Mechanistic investigations suggest that the state-dependency stems from a combination of differential protein turnover rates and extensive ITK mRNA alternative splicing. We further introduce the most comprehensive list to date of proteins involved in splicing and leverage cysteine- and protein-directed activity-based protein profiling with electrophilic scout fragments to demonstrate covalent ligandability for many classes of splicing factors and splicing regulators in T cells. Taken together, our findings show how chemical perturbation of splicing can lead to immune state-dependent changes in protein expression and provide evidence for the broad potential to target splicing factors with covalent chemistry.

中文翻译：

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T 细胞剪接的共价靶向


尽管人们对剪接的治疗靶向产生了浓厚的兴趣，但很少有化学探针可用于参与剪接的蛋白质。在这里，我们表明，精心设计的立体异构体丙烯酰胺 EV96 及其类似物通过靶向核心剪接因子之一导致白细胞介素 2 诱导型 T 细胞激酶 （ITK） 的选择性 T 细胞状态依赖性丢失 SF3B1。机制研究表明，状态依赖性源于不同的蛋白质周转率和广泛的 ITK mRNA 选择性剪接的组合。我们进一步介绍了迄今为止参与剪接的蛋白质的最全面的列表，并利用亲电侦察片段进行基于半胱氨酸和蛋白质定向活性的蛋白质分析，以证明 T 细胞中许多类别的剪接因子和剪接调节因子的共价配体性。综上所述，我们的研究结果显示了剪接的化学扰动如何导致蛋白质表达的免疫状态依赖性变化，并为用共价化学靶向剪接因子的广泛潜力提供了证据。