来源：生物谷 作者: ipsvirus 时间: 2015-10-21 15:42 Deubiquitinase MYSM1 Regulates Innate Immunity through Inactivation of TRAF3 and TRAF6 Complexes
Swarupa Panda, Jonas A. Nilsson, Nelson O. Gekara
Highlights
•MYSM1 inhibits PRR pathways for pro-inflammatory and type I IFN gene induction
•MYSM1 transiently accumulates in the cytoplasm upon microbial challenge
•MYSM1 interacts with and inactivates TRAF3 and TRAF6 via its SWIRM and MPN domains
•MYSM1 protects against sepsis but renders mice more susceptible to viral infection
Summary
Pattern-recognition receptors (PRRs) including Toll-like receptors, RIG-I-like receptors, and cytoplasmic DNA receptors are essential for protection against pathogens but require tight control to avert inflammatory diseases. The mechanisms underlying this strict regulation are unclear. MYSM1 was previously described as a key component of epigenetic signaling machinery. We found that in response to microbial stimuli, MYSM1 accumulated in the cytoplasm where it interacted with and inactivated TRAF3 and TRAF6 complexes to terminate PRR pathways for pro-inflammatory and type I interferon responses. Consequently, Mysm1 deficiency in mice resulted in hyper-inflammation and enhanced viral clearance but also susceptibility to septic shock. We identified two motifs in MYSM1 that were essential for innate immune suppression: the SWIRM domain that interacted with TRAF3 and TRAF6 and the metalloproteinase domain that removed K63 polyubiquitins. This study identifies MYSM1 as a key negative regulator of the innate immune system that guards against an overzealous self-destructive immune response.
