对于JAK-STAT信号传递的酶独立小分子抑制
Danny Hung-Chieh Chou1, Amedeo Vetere, Amit Choudhary2
1‡Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, Massachusetts 02138, United States.
Journal of the American Chemical Society
|June 5, 2015
概括
小分子BRD0476通过USP9X抑制JAK-STAT通路来保护胰腺细胞,而不是通过抑制JAK激酶活性来保护胰腺细胞. 这表明USP9X是调节炎症的新目标.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 药理学 药理学是指药理学的学科.
背景情况:
- 现型查对于药物发现至关重要,但确定分子标和作用机制 (MoA) 仍然具有挑战性.
- 胰腺β细胞亡是糖尿病的关键因素,了解其调节对于治疗的发展至关重要.
研究的目的:
- 阐明小分子BRD0476的细胞内标和MoA,这是胰腺β细胞亡的新型抑制剂.
- 研究该化合物对Janus激酶2 (JAK2) 和信号传感器以及转录1 (STAT1) 信号通路的激活的影响.
主要方法:
- 在大鼠β细胞中进行定量蛋白质组分析,以确定BRD0476.6的细胞内标.
- 通过RNA干扰 (RNAi) 和CRISPR/Cas9基因编辑来验证目标.
- 用已知抑制剂对已识别的目标进行逆化学遗传学.
- 位点定向的突变发生,以调查酸化和无化之间的相互作用.
主要成果:
- BRD0476抑制干扰素- (IFN-γ) 诱导的JAK2/STAT1信号传递,促进β细胞存活而不抑制JAK激酶活性.
- 定量蛋白质组学确定了泛素特异性酶9X (USP9X) 作为细胞内标.
- 击败USP9X和抑制USP9X模仿了BRD0476的影响.
- 突变性表明BRD0476的MoA涉及JAK2酸化和无处不在化之间的竞争.
结论:
- 表型查与MoA研究相结合,可以对已建立的信号通路产生新的见解.
- USP9X被确定为调节细胞炎症中的JAK2活性并促进β细胞存活的潜在治疗标.
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