Deubiquitinating enzyme MINDY2 regulates TNF-α-induced cell death by targeting RIPK1

Area of Science:

• Molecular Biology
• Immunology
• Cell Death Pathways

Background:

• Ubiquitination is critical for tumor necrosis factor (TNF)-α signaling.
• Understanding how ubiquitination regulates TNF-α signaling is essential for comprehending cellular responses to inflammation and stress.

Purpose of the Study:

• To identify ubiquitination-modifying enzymes that regulate TNF-α signaling.
• To elucidate the role of the deubiquitinating enzyme MINDY2 in TNF-α-induced cell death and inflammatory responses.

Main Methods:

• Conducted a screen using a gene expression library of ubiquitination-modifying enzymes.
• Investigated the effect of MINDY2 on RIPK1 ubiquitination at the K612 site.
• Generated and analyzed MINDY2-knockout mice subjected to TNF-α challenge.

Main Results:

• Identified MINDY2 as an inhibitor of TNF-α-induced cell death.
• Demonstrated that MINDY2 modulates RIPK1 ubiquitination, affecting RIPK1 recruitment to TNFR1 and complex 1 signaling.
• MINDY2-deficient mice showed exacerbated hypothermia, mortality, and intestinal damage following TNF-α challenge.

Conclusions:

• MINDY2 acts as a critical checkpoint in regulating RIPK1-dependent cell death.
• MINDY2 deficiency enhances susceptibility to TNF-α-mediated tissue damage in vivo.
• These findings highlight MINDY2's protective role in inflammatory conditions involving TNF-α signaling.