Versteeg Gijs A, Benke Stefan, García-Sastre Adolfo, Rajsbaum Ricardo
Max F. Perutz Laboratories, Department of Microbiology, Immunobiology and Genetics, University of Vienna, Vienna, Austria.
Max F. Perutz Laboratories, Department of Microbiology, Immunobiology and Genetics, University of Vienna, Vienna, Austria.
Cytokine Growth Factor Rev. 2014 Oct;25(5):563-76. doi: 10.1016/j.cytogfr.2014.08.001. Epub 2014 Aug 13.
During the immune response, striking the right balance between positive and negative regulation is critical to effectively mount an anti-microbial defense while preventing detrimental effects from exacerbated immune activation. Intra-cellular immune signaling is tightly regulated by various post-translational modifications, which allow for this dynamic response. One of the post-translational modifiers critical for immune control is ubiquitin, which can be covalently conjugated to lysines in target molecules, thereby altering their functional properties. This is achieved in a process involving E3 ligases which determine ubiquitination target specificity. One of the most prominent E3 ligase families is that of the tripartite motif (TRIM) proteins, which counts over 70 members in humans. Over the last years, various studies have contributed to the notion that many members of this protein family are important immune regulators. Recent studies into the mechanisms by which some of the TRIMs regulate the innate immune system have uncovered important immune regulatory roles of both covalently attached, as well as unanchored poly-ubiquitin chains. This review highlights TRIM evolution, recent findings in TRIM-mediated immune regulation, and provides an outlook to current research hurdles and future directions.
在免疫反应过程中,在正向和负向调节之间取得恰当平衡对于有效发起抗微生物防御同时防止免疫激活加剧产生的有害影响至关重要。细胞内免疫信号传导受到各种翻译后修饰的严格调控,从而实现这种动态反应。对免疫控制至关重要的一种翻译后修饰因子是泛素,它可以与靶分子中的赖氨酸共价结合,从而改变其功能特性。这一过程由决定泛素化靶标特异性的E3连接酶参与完成。最突出的E3连接酶家族之一是三联基序(TRIM)蛋白家族,在人类中有70多个成员。在过去几年中,各种研究表明该蛋白家族的许多成员都是重要的免疫调节因子。最近对一些TRIM蛋白调节先天免疫系统机制的研究揭示了共价连接的以及未锚定的多聚泛素链的重要免疫调节作用。本综述重点介绍了TRIM蛋白的进化、TRIM介导的免疫调节的最新发现,并对当前的研究障碍和未来方向进行了展望。