Proteo-Science Center (PROS), Ehime University, 3 Bunkyo-cho, Matsuyama, Ehime, 790-8577, Japan.
Department of Immunology, Graduate School of Medicine, Ehime University, Shitsukawa, Toon, 791-0295, Ehime, Japan.
Sci Rep. 2019 Nov 22;9(1):17335. doi: 10.1038/s41598-019-53856-1.
The transcription factor GATA3 is a master regulator that modulates T helper 2 (Th2) cell differentiation and induces expression of Th2 cytokines, such as IL-4, IL-5, and IL-13. Th2 cytokines are involved in the protective immune response against foreign pathogens, such as parasites. However, excessive production of Th2 cytokines results in type-2 allergic inflammation. Therefore, the application of a GATA3 inhibitor provides a new therapeutic strategy to regulate Th2 cytokine production. Here, we established a novel high-throughput screening system for an inhibitor of a DNA-binding protein, such as a transcription factor, and identified pyrrothiogatain as a novel inhibitor of GATA3 DNA-binding activity. Pyrrothiogatain inhibited the DNA-binding activity of GATA3 and other members of the GATA family. Pyrrothiogatain also inhibited the interaction between GATA3 and SOX4, suggesting that it interacts with the DNA-binding region of GATA3. Furthermore, pyrrothiogatain significantly suppressed Th2 cell differentiation, without impairing Th1 cell differentiation, and inhibited the expression and production of Th2 cytokines. Our results suggest that pyrrothiogatain regulates the differentiation and function of Th2 cells via inhibition of GATA3 DNA binding activity, which demonstrates the efficiency of our drug screening system for the development of novel small compounds that inhibit the DNA-binding activity of transcription factors.
转录因子 GATA3 是一种主调控因子，调节辅助性 T 细胞 2（Th2）细胞分化，并诱导 Th2 细胞因子的表达，如 IL-4、IL-5 和 IL-13。Th2 细胞因子参与针对寄生虫等外来病原体的保护性免疫反应。然而，Th2 细胞因子的过度产生会导致 2 型过敏炎症。因此，应用 GATA3 抑制剂为调节 Th2 细胞因子产生提供了一种新的治疗策略。在这里，我们建立了一种新型的高通量筛选系统，用于筛选 DNA 结合蛋白（如转录因子）的抑制剂，并鉴定出吡咯硫代胍作为 GATA3 DNA 结合活性的新型抑制剂。吡咯硫代胍抑制 GATA3 和 GATA 家族其他成员的 DNA 结合活性。吡咯硫代胍还抑制 GATA3 与 SOX4 之间的相互作用，表明它与 GATA3 的 DNA 结合区域相互作用。此外，吡咯硫代胍显著抑制 Th2 细胞分化，而不损害 Th1 细胞分化，并抑制 Th2 细胞因子的表达和产生。我们的结果表明，吡咯硫代胍通过抑制 GATA3 DNA 结合活性来调节 Th2 细胞的分化和功能，这证明了我们的药物筛选系统对于开发新型小分子抑制剂以抑制转录因子的 DNA 结合活性的有效性。
