1. Academic Validation
  2. ERK/Smurf1 regulates non-canonical pyroptosis by prompting Caspase-11 ubiquitination

ERK/Smurf1 regulates non-canonical pyroptosis by prompting Caspase-11 ubiquitination

  • Cell Death Differ. 2026 Jan 8. doi: 10.1038/s41418-025-01654-w.
Chenglong Zhu # 1 2 3 Wangzheqi Zhang # 2 3 Yan Liao # 2 3 Ruoyu Jiang 3 4 Lindong Cheng 2 3 Yi Wang 1 2 3 Tian Zhou 2 3 Yijie Tao 5 6 7 Sheng Xu 8 Yizhi Yu 9 Zui Zou 10 11 12
Affiliations

Affiliations

  • 1 National Key Laboratory of Immunity and Inflammation, Naval Medical University, Shanghai, China.
  • 2 Faculty of Anesthesiology, Changhai Hospital, Naval Medical University, Shanghai, China.
  • 3 School of Anesthesiology, Naval Medical University, Shanghai, China.
  • 4 Department of Biochemistry and Molecular Biology, College of Basic Medical Sciences, Naval Medical University, Shanghai, China.
  • 5 National Key Laboratory of Immunity and Inflammation, Naval Medical University, Shanghai, China. [email protected].
  • 6 Faculty of Anesthesiology, Changhai Hospital, Naval Medical University, Shanghai, China. [email protected].
  • 7 School of Anesthesiology, Naval Medical University, Shanghai, China. [email protected].
  • 8 National Key Laboratory of Immunity and Inflammation, Naval Medical University, Shanghai, China. [email protected].
  • 9 National Key Laboratory of Immunity and Inflammation, Naval Medical University, Shanghai, China. [email protected].
  • 10 National Key Laboratory of Immunity and Inflammation, Naval Medical University, Shanghai, China. [email protected].
  • 11 Faculty of Anesthesiology, Changhai Hospital, Naval Medical University, Shanghai, China. [email protected].
  • 12 School of Anesthesiology, Naval Medical University, Shanghai, China. [email protected].
  • # Contributed equally.
Abstract

Sepsis, a devastating microbe-induced inflammatory response, culminates in multi-organ dysfunction, with Pyroptosis mediated by the non-canonical inflammasome being a pivotal factor. The mouse Caspase-11, central to this pathway, is directly activated by cytoplasmic lipopolysaccharide (LPS). Although ubiquitination is known to tightly regulate the inflammatory response in Pyroptosis, its role in modulating the non-canonical inflammasome remains enigmatic. In this study, we unveil that the E3 ubiquitin Ligase Smurf1 is a critical negative regulator of the non-canonical inflammasome pathway. Smurf1 orchestrates K48-linked polyubiquitination of Caspase-11 at K245 and K247 residues, leading to its degradation via the 26S Proteasome. This process is further amplified by ERK phosphorylation of Smurf1 at the S148 site. In parallel, Caspase-11 modulates Smurf1 protein content through cleavage. Notably, macrophage-specific Smurf1 deficiency exacerbates sepsis-induced mortality in mice, attributed to the hyperactivation of the non-canonical inflammasome. Conversely, targeted supplementation of Smurf1 in macrophages mitigates the high mortality and inflammatory response associated with sepsis. Thus, Smurf1 emerges as a key player in modulating the activation of the non-canonical inflammasome in response to Gram-negative Bacterial infections.

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