来自UNC93B1的释放加强了特定TLR的分隔激活
Olivia Majer1, Bo Liu1, Brian J Woo1
1Division of Immunology and Pathogenesis, Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA.
Nature
|September 24, 2019
概括
一种新的检查点机制确保了仅在内体内发生托尔类受体9 (TLR9) 的激活. 这涉及其伴随者UNC93B1的调节释放,防止自身免疫反应,并确保适当的免疫信号.
科学领域:
- 免疫学
- 分子生物学
- 细胞生物学
背景情况:
- 核酸感应型受体 (TLR) 对于检测微生物成分至关重要,但必须严格调节以防止自身免疫.
- 细胞内定位是区分自我与非自我核酸的关键,但控制细胞内TLR激活的机制仍然不清楚.
研究的目的:
- 阐明防止内体外Toll-like受体9 (TLR9) 过早激活的分子机制.
- 确定贩运护理人UNC93B1在调节TLR9定位和激活中的作用.
主要方法:
- 通过基因突变和人为结合,研究了TLR9与其伴侣UNC93B1之间的相互作用.
- 从UNC93B1内分析了TLR9,TLR3和TLR7的释放动态.
- 评估了受损UNC93B1释放对TLR9连体结合和下游信号传导的影响.
主要成果:
- 一个新的检查点机制被确定,其中TLR9从UNC93B1完全释放到内体内,从而使联体结合和信号传递成为可能.
- 突变在UNC93B1中增强其对TLR9的亲和力,或人工绑定损害释放,导致TLR9信号缺陷.
- 在内体中,TLR9和TLR3与UNC93B1分离,而TLR7仍然结合,这表明不同的内体TLR具有不同的调节机制.
结论:
- 这项研究定义了一个关键检查点,用于区分TLR9激活,由内分体内UNC93B1的调节释放介导.
- 这些发现揭示了控制个人内体TLR激活的独特机制,这对于预防自身免疫性疾病至关重要.
- 这项工作提供了对核酸先天免疫反应的精确调节的见解.
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