Role of iRhoms and ADAM17 in EGFR and TNFalpha signaling

iRhoms 和 ADAM17 在 EGFR 和 TNFα 信号转导中的作用

• 批准号: 10544994
• 负责人: Carl Peter Blobel
• 金额: $ 41.14万
• 依托单位: HOSPITAL FOR SPECIAL SURGERY
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-01-01 至 2024-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10544994
• 关键词: Anabolism; Autoimmune Diseases; Binding; Biochemical; Biological; Biological Assay; Cell surface; Cells; Complex; Cytoplasmic Tail; Cytoprotection; Development; Disease; Disintegrins; Endoplasmic Reticulum; Epidermal Growth Factor Receptor; Genetic; Goals; Immune; Inflammatory; Ligands; Malignant Neoplasms; Membrane; Metalloproteases; Molecular; Mus; Myeloid Cells; Pathology; Pathway interactions; Property; Proteins; Receptor Protein-Tyrosine Kinases; Regulation; Role; Septic Shock; Signal Pathway; Signal Transduction; Signaling Molecule; Site; Structure; TNF gene; Transmembrane Domain; cancer therapy; cytokine; in vivo; intestinal barrier; mutant; novel; skin barrier

ADAM17 (a disintegrin and metalloprotease 17) is a cell surface metalloprotease with vital roles in regulating the EGF-receptor as well as TNFa signaling. EGFR-ligands and TNFa are made as membrane- anchored precursors that must be proteolytically released or “shed” to activate the soluble signaling molecule. Mice lacking ADAM17 resemble mice lacking the EGFR, providing genetic evidence for the essential role of ADAM17 in EGFR signaling. Moreover, inactivation of ADAM17 in myeloid cells protects from septic shock in mice, which is caused by the release of soluble TNFa from myeloid cells. These functions establish ADAM17 as an important potential target for the treatment of EGFR- and TNFa-dependent pathologies such as cancer and autoimmune diseases. ADAM17 activity is highly regulated and is influenced by numerous signaling pathways. How these pathways functionally intersect with ADAM17 and how ADAM17 is activated are key questions that are the main focus of my lab. Previously, we had found that ADAM17 is regulated by its transmembrane domain (TMD), which ultimately led us to identify the seven-membrane spanning iRhoms1 and 2 (iR1, iR2) as novel regulators of ADAM17. We showed that iR2 controls the function of ADAM17 in immune cells and that inactivation of iR1 and iR2 abolishes all functions of ADAM17 in mice, thereby providing biochemical, cell biological and genetic evidence that iR1 and iR2 are the long sought-after regulators of ADAM17. The main goals of the current proposal are to understand how iR1 and 2 integrate, interpret and execute the signals that drive the activation of the ADAM17/EGFR- and ADAM17/TNFa signaling pathway. In the next 5 years, we will explore the biosynthesis and regulation of the iRhom/ADAM17 complexes and how they target substrates in a selective manner. We know that the cytoplasmic domain of ADAM17 is required to stabilize the protein, most likely so that it can assembly with an iRhom in the endoplasmic reticulum (ER). We would like to identify the factors that stabilize ADAM17 and the sites in ADAM17 and the iRhoms that promote their interaction. Once the iRhoms have assembled with ADAM17, they move to the cell surface. We will use mutant iRhoms that are retained in the ER to identify binding partners that regulate their export from the ER. We will also explore how the substrate selectivity of iRhoms is determined at the molecular level. Finally, ADAM17 is unique in that it responds rapidly to several different signaling pathways, a property that is thought to be essential for its role in skin and intestinal barrier protection. We will study the molecular details of the on/off switch for ADAM17, and generate mice that express a constitutively active ADAM17 that cannot be activated to determine how important this unique property of ADAM17 is in vivo. Together, our planned studies will resolve the most pressing current questions regarding the regulation of ADAM17, a major cellular sheddase that is critical for TNFa and EGFR signaling and a target for treatment of cancer and autoimmune diseases, by its recently discovered upstream regulators iR1 and iR2.

ADAM 17（一种去整合素和金属蛋白酶17）是一种细胞表面金属蛋白酶，在细胞凋亡中起重要作用。 调节EGF受体以及TNF α信号传导。EGFR配体和TNF α被制成膜- 锚定的前体必须被蛋白水解释放或“脱落”以激活可溶性信号分子。 缺乏ADAM 17的小鼠与缺乏EGFR的小鼠相似，这为ADAM 17的重要作用提供了遗传学证据。 EGFR信号转导中的ADAM 17。此外，髓系细胞中ADAM 17的失活可保护受试者免受感染性休克。 这是由骨髓细胞释放可溶性TNF α引起的。这些功能建立了ADAM 17 作为治疗EGFR-和TNF α-依赖性疾病如癌症的重要潜在靶点 和自身免疫性疾病。ADAM 17活性受到高度调节，并受到许多信号传导的影响。 途径。这些通路如何在功能上与ADAM 17交叉以及ADAM 17如何被激活是关键 我的实验室主要关注的问题。以前，我们已经发现ADAM 17是由其 跨膜结构域（TMD），这最终使我们确定了七跨膜iRhoms 1和 2（iR 1，iR 2）作为ADAM 17的新型调节剂。我们发现iR 2在免疫过程中控制着ADAM 17的功能， iR 1和iR 2的失活消除了小鼠中ADAM 17的所有功能，从而提供了 生物化学、细胞生物学和遗传学证据表明，iR 1和iR 2是长期寻求的调节剂， ADAM 17.当前提案的主要目标是了解iR 1和2如何集成、解释和 执行驱动ADAM 17/EGFR-和ADAM 17/TNFa信号传导通路的激活的信号。 在接下来的5年里，我们将探索iRhom/ADAM 17复合物的生物合成和调控， 它们如何以选择性的方式靶向底物。我们知道ADAM 17的胞质结构域是 这是稳定蛋白质所必需的，最有可能的是使其可以与内质网中的iRhom组装 （ER）。我们希望确定稳定ADAM 17的因素以及ADAM 17和iRhoms中的位点， 促进他们的互动。一旦iRhom与ADAM 17组装，它们就会移动到细胞表面。 我们将使用保留在ER中的突变iRhom来鉴定调节其输出的结合伴侣 急诊室的我们还将探讨如何在分子水平上确定iRhoms的底物选择性。 最后，ADAM 17的独特之处在于它对几种不同的信号传导途径反应迅速，这是一种被广泛接受的特性。 被认为是其在皮肤和肠道屏障保护中的作用所必需的。我们将研究 启动/关闭ADAM 17的开关，并产生表达组成型活性ADAM 17的小鼠，这种活性ADAM 17不能被 以确定这种独特的特性在体内的重要性。 我们计划的研究将共同解决目前最紧迫的问题， ADAM 17是一种主要的细胞脱落酶，对TNF α和EGFR信号传导至关重要，也是治疗肿瘤的靶点。 癌症和自身免疫性疾病，通过其最近发现的上游调控因子iR 1和iR 2。