Department of Integrative Biotechnology and Biomedical Institute for Convergence at SKKU (BICS), Sungkyunkwan University, Suwon 16419, Republic of Korea.
Institute for Translational Medicine, The Affiliated Hospital of Qingdao University, Qingdao 266000, China.
Mediators Inflamm. 2024 Oct 26;2024:8634515. doi: 10.1155/2024/8634515. eCollection 2024.
Inflammation is a vital immune defense mechanism regulated by Toll-like receptors (TLRs) and the nuclear factor-kappa B (NF-B) pathway. TANK-binding kinase 1 (TBK1) is central to immunity and inflammation and influences antiviral responses and cellular processes. However, the precise role of TBK1 in modulating the NF-B pathway through interactions with other proteins, such as spleen tyrosine kinase (Syk), remains poorly understood. As dysregulation of TBK1 and NF-B can lead to a variety of diseases, they are important therapeutic targets. In this work, inflammatory processes involving the TBK1-Syk-NF-B pathway were elucidated using lipopolysaccharide (LPS)-induced macrophages; human embryonic kidney 293 (HEK293) cells overexpressing MyD88, TBK1, and Syk proteins and their mutants; and real-time polymerase chain reaction (PCR), immunoblotting analyses, and kinase assays. TBK1 was activated in LPS-, poly I:C-, and Pam3CSK-stimulated macrophages. Transcript levels of , , and were increased in cells overexpressing TBK1 but not in cells overexpressing TBK1 K38A. The transcription of , , and and NF-B luciferase activity were inhibited by silencing TBK1 in LPS-stimulated RAW264.7 cells and MyD88-transfected HEK293 cells. Syk was the key mediator of the TBK1-dependent NF-B pathway and bound directly to the coiled coil domain of TBK1, which was necessary to activate Syk and the Syk-p85 pathway. This research advances the understanding of the role of TBK1 in NF-B signaling, emphasizing Syk as a key mediator. The interaction between TBK1 and Syk has potential for precise immune modulation that can be applied to treat immune-related disorders.
炎症是一种由 Toll 样受体 (TLRs) 和核因子-κB (NF-κB) 途径调节的重要免疫防御机制。TANK 结合激酶 1 (TBK1) 是免疫和炎症的核心，影响抗病毒反应和细胞过程。然而，TBK1 通过与其他蛋白质（如脾酪氨酸激酶 (Syk)）相互作用来调节 NF-κB 途径的确切作用仍知之甚少。由于 TBK1 和 NF-κB 的失调可能导致多种疾病，因此它们是重要的治疗靶点。在这项工作中，使用脂多糖 (LPS) 诱导的巨噬细胞、过表达 MyD88、TBK1 和 Syk 蛋白及其突变体的人胚肾 293 (HEK293) 细胞以及实时聚合酶链反应 (PCR)、免疫印迹分析和激酶测定，阐明了涉及 TBK1-Syk-NF-κB 途径的炎症过程。在 LPS、聚 I:C 和 Pam3CSK 刺激的巨噬细胞中激活了 TBK1。在过表达 TBK1 的细胞中转录水平增加，但在过表达 TBK1 K38A 的细胞中没有增加。在 LPS 刺激的 RAW264.7 细胞和转染 MyD88 的 HEK293 细胞中沉默 TBK1 可抑制 、 、 和 NF-κB 荧光素酶活性。Syk 是 TBK1 依赖性 NF-κB 途径的关键介质，直接与 TBK1 的卷曲螺旋结构域结合，这对于激活 Syk 和 Syk-p85 途径是必需的。这项研究推进了对 TBK1 在 NF-κB 信号转导中的作用的理解，强调了 Syk 作为关键介质。TBK1 和 Syk 之间的相互作用具有精确免疫调节的潜力，可用于治疗与免疫相关的疾病。
