Article

The role of ubiquitylation in immune defence and pathogen evasion

Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, Texas 75390-9148, USA.
Nature Reviews Immunology (Impact Factor: 33.84). 12/2011; 12(1):35-48. DOI: 10.1038/nri3111
Source: PubMed

ABSTRACT Ubiquitylation is a widely used post-translational protein modification that regulates many biological processes, including immune responses. The role of ubiquitin in immune regulation was originally uncovered through studies of antigen presentation and the nuclear factor-κB family of transcription factors, which orchestrate host defence against microorganisms. Recent studies have revealed crucial roles of ubiquitylation in many aspects of the immune system, including innate and adaptive immunity and antimicrobial autophagy. In addition, mounting evidence indicates that microbial pathogens exploit the ubiquitin pathway to evade the host immune system. Here, we review recent advances on the role of ubiquitylation in host defence and pathogen evasion.

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    • "signaling is extensively modulated by ubiquitin at various points (Belgnaoui et al., 2012; Jiang et al., 2012; Maelfait and Beyaert, 2012; Nakhaei et al., 2009b; Zeng et al., 2010; Zeng et al., 2009; Zhong et al., 2010). Notably, the ubiquitin ligase RNF5 (RMA1) catalyzes K48-linked polyubiquitination of STING, promoting the proteasome-mediated degradation of STING (Zhong et al., 2009). "
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    • "Modifying a protein with ubiquitin can result in a variety of outcomes other than degradation. These include activation of signaling proteins, regulation of protein-protein interactions, and relocalization of proteins within a cell (Jiang and Chen, 2012). Herein, we focus on the degradation of ubiquitylated proteins. "
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    • "known to exploit the ubiquitin pathway to evade host defence mechanisms (Jiang and Chen, 2011), it will be of particular interest to explore possible functions of this class of CRL3 substrate adaptors in innate immunity and bacterial diseases. Precedent for important plant immunity roles stems from another class of plant BTB proteins, which includes Arabidopsis NPR1, a master regulator of plant immunity that controls the onset of systemic acquired resistance (SAR) to a broad spectrum of pathogens. "
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