ROLE OF NEK7 PROTEIN IN NLRP3 INFLAMMASOME ACTIVATION AND INFLAMMATION

项目概要/摘要 NACHT，LRR and PYD domains-containing protein 3（NLRP3）属于Nod-like-receptor（NLR） 触发炎性体组装的蛋白质，炎性体是介导半胱天冬酶-1的分子平台 生物活性IL-1β和IL-18的活化、加工和分泌。除了在以下方面发挥关键作用外， 天然免疫，NLRP 3炎性体的失调与遗传和获得性免疫有关。 炎性疾病，如Cryopyrin相关的自身炎性综合征，痛风，克罗恩病， 老年痴呆症，糖尿病和动脉粥样硬化。尽管NLRP的医学重要性3 虽然炎症小体的存在，但其被激活的机制仍然难以捉摸。利用蛋白质组学方法来揭示 在巨噬细胞中与NLRP 3相互作用的关键因子，我们鉴定了Nek 7蛋白激酶作为NLRP 3- NLRP 3是一种相互作用蛋白，其对于NLRP 3炎性体的组装是必需的。Nek 7与 NLRP 3处于静息状态，并且这种相互作用在NLRP 3激活期间增强。巨噬细胞中 Nek 7耗尽后，caspase-1活化和IL-1 β分泌在对刺激的反应中被废除， NLRP 3激活。相反，Nek 7不是NLRC 4和AIM 2炎性小体激活所必需的。 Nek 7在NLRP 3炎性体活化中的关键和特异性作用是出乎意料的，因为 Nek 7是调节胞质分裂的激酶家族的成员。该提案的目的是定义 Nek 7调节NLRP 3炎性体活化的分子机制。基于我们 初步结果，我们的主要假设是Nek 7蛋白激酶调节NLRP 3炎性体 通过促进炎性小体的组装来活化。此外，我们假设Nek 7 有助于炎性疾病的诱导和/或进展。为了验证这些假设，我们建议 表征Nek 7调节NLRP 3炎性小体活化的机制和Nek 7的作用 使用依赖于通过NLRP 3分泌IL-1 β的炎症动物模型进行体内研究。理解的作用 NLRP 3炎性小体激活中的Nek 7有望为新的免疫抑制剂的开发提供关键的见解。 炎症性疾病的治疗策略。

Project Summary/Abstract NACHT, LRR and PYD domains-containing protein 3 (NLRP3) belongs to a class of Nod-like-receptor (NLR) proteins that trigger the assembly of the inflammasome, a molecular platform that mediates caspase-1 activation and processing and secretion of biologically active IL-1β and IL-18. In addition to its critical role in innate immunity, dysregulation of the NLRP3 inflammasome has been linked to both inherited and acquired inflammatory disorders, such as Cryopyrin-associated autoinflammatory syndrome, gout, Crohn’s disease, Alzheimer’s disease, diabetes and atherosclerosis. Despite the medical importance of the NLRP3 inflammasome, the mechanism by which it is activated remains elusive. Using a proteomics approach to reveal critical factors that interact with NLRP3 in macrophages, we identified the Nek7 protein kinase as a NLRP3- interacting protein that is essential for the assembly of the NLRP3 inflammasome. Nek7 is associated with NLRP3 in the resting state, and this interaction is enhanced during NLRP3 activation. In macrophages depleted with Nek7, caspase-1 activation and IL-1 secretion are abrogated in response to stimuli that trigger NLRP3 activation. In contrast, Nek7 is not required for the activation of the NLRC4 and AIM2 inflammasomes. The critical and specific role of Nek7 in the activation of the NLRP3 inflammasome is unexpected because Nek7 is a member of a kinase family that regulates cytokinesis. The goal of this proposal is to define the molecular mechanism by which Nek7 regulates the activation of the NLRP3 inflammasome. Based on our preliminary results, our primary hypothesis is that the Nek7 protein kinase regulates NLRP3 inflammasome activation by promoting the assembly of the inflammasome. Furthermore, we hypothesize that Nek7 contributes to the induction and/or progression of inflammatory disease. To test these hypotheses, we propose characterizing the mechanism by which Nek7 regulates NLRP3 inflammasome activation and the role of Nek7 in vivo using animals models of inflammation that rely on IL-1 secretion via NLRP3. Understanding the role of Nek7 in NLRP3 inflammasome activation is expected to provide critical insight into the development of novel therapeutic strategies for inflammatory diseases.