Optineurin (OPTN) is a multifunctional protein involved in autophagy and secretion, as well as nuclear factor B (NF-B) and IRF3 signalling, and OPTN mutations are associated with several human diseases. Here, we show that, in response to viral RNA, OPTN translocates to foci in the perinuclear region, where it negatively regulates NF-B and IRF3 signalling pathways and downstream pro-inflammatory cytokine secretion. These OPTN foci consist of a tight cluster of small membrane vesicles, which are positive for ATG9A. Disease mutations in OPTN linked to primary open-angle glaucoma (POAG) cause aberrant foci formation in the absence of stimuli, which correlates with the ability of OPTN to inhibit signalling. By using proximity labelling proteomics, we identify the linear ubiquitin assembly complex (LUBAC), CYLD and TBK1 as part of the OPTN interactome and show that these proteins are recruited to this OPTN-positive perinuclear compartment. Our work uncovers a crucial role for OPTN in dampening NF-B and IRF3 signalling through the sequestration of LUBAC and other positive regulators in this viral RNA-induced compartment, leading to altered pro-inflammatory cytokine secretion.

Optineurin (OPTN) 是一种多功能蛋白，参与自噬和分泌以及核因子 B (NF-B) 和 IRF3 信号传导，OPTN突变与多种人类疾病相关。在这里，我们发现，响应病毒 RNA，OPTN 易位到核周区域的病灶，在那里它负向调节 NF-B 和 IRF3 信号通路以及下游促炎细胞因子的分泌。这些 OPTN 病灶由紧密的小膜囊泡簇组成，这些囊泡对 ATG9A 呈阳性。与原发性开角型青光眼 (POAG) 相关的 OPTN 疾病突变会在没有刺激的情况下导致异常病灶形成，这与 OPTN 抑制信号传导的能力相关。通过使用邻近标记蛋白质组学，我们鉴定了线性泛素组装复合物 (LUBAC)、CYLD 和 TBK1 作为 OPTN 相互作用组的一部分，并表明这些蛋白质被招募到这个 OPTN 阳性核周区室。我们的工作揭示了 OPTN 通过在病毒 RNA 诱导的区室中隔离 LUBAC 和其他正调节因子来抑制 NF-B 和 IRF3 信号传导，从而导致促炎细胞因子分泌改变。