Chu Xiufeng, Zhang Ting, Bukhari Ihtisham, Hu Mei, Xu Jixuan, Xing Yamin, Liang Xinfeng, Zhang Zisen, Zheng Pengyuan
Department of Oncology, The Fifth Affiliated Hospital of Zhengzhou University, Zhengzhou, China.
Marshall B. J. Medical Research Center, The Fifth Affiliated Hospital of Zhengzhou University, Zhengzhou, China.
Cell Death Dis. 2025 Mar 17;16(1):181. doi: 10.1038/s41419-025-07475-6.
Gasdermin D (GSDMD) is a critical pyroptosis mediator, consisting of one N-terminal pore-forming domain and one C-terminal auto-inhibitory domain. The free N-terminal domain (GD-NT), which is released through caspase-1/11 cleavage, exhibits distinct features from the full-length GSDMD (GD-FL), including oligomerization, membrane translocation, and pore-formation. However, the underlying mechanisms are not well elucidated. Here, we found that GD-NT, but not GD-FL, was massively ubiquitinated in cells. The K63-linked polyubiquitination of GD-NT at Lys236/237 (human/mouse), catalyzed by TRAF1, directly prompted its membrane translocation and pore-formation during pyroptosis. Inhibition of GD-NT ubiquitination via site-directed mutations or the UBA1 inhibitor PYR-41 suppressed cell death in several pyroptosis cell models. Additionally, applying PYR-41 in septic mice efficiently suppressed the release of IL-18 and TNFα. Thus, GD-NT ubiquitination is a key regulatory mechanism controlling its membrane localization and activation, which may provide a novel target for modulating immune activity in pyroptosis-related diseases.
Gasdermin D（GSDMD）是一种关键的细胞焦亡介质，由一个N端成孔结构域和一个C端自抑制结构域组成。通过半胱天冬酶-1/11切割释放的游离N端结构域（GD-NT）与全长GSDMD（GD-FL）具有不同的特征，包括寡聚化、膜易位和孔形成。然而，其潜在机制尚未得到充分阐明。在这里，我们发现GD-NT而非GD-FL在细胞中大量泛素化。由TRAF1催化的GD-NT在赖氨酸236/237（人/小鼠）处的K63连接多聚泛素化直接促使其在细胞焦亡过程中的膜易位和孔形成。通过定点突变或UBA1抑制剂PYR-41抑制GD-NT泛素化可在几种细胞焦亡细胞模型中抑制细胞死亡。此外，在脓毒症小鼠中应用PYR-41可有效抑制IL-18和TNFα的释放。因此，GD-NT泛素化是控制其膜定位和激活的关键调节机制，这可能为调节细胞焦亡相关疾病中的免疫活性提供一个新的靶点。
