Identification of novel pathways causing NF1-driven Schwann cell tumors

摘要 NF1基因产物，神经纤维素，在1990年被发现，但基本的问题 关于其胞内位置(S)、结合伙伴和信号转导仍未得到回答 属性。已知大的(&gt；200kd)抑癌蛋白含有一个小的 Ras蛋白的转换域，因此NF1功能的丧失导致Ras激活 细胞刺激。剩余的NF1序列可以与伴侣SPRED1和 体外和/或特定细胞类型中的其他蛋白质。在Schwan细胞中，NF1缺失导致 神经纤维瘤的形成，周围神经的肿瘤。目前还不清楚是哪一个 相互作用伙伴和RAS蛋白在雪旺细胞中是相关的。在此，我们建议 确定NF1相互作用伙伴，包括与Schwann有关的RAS蛋白 细胞肿瘤的发生。这是因为在哺乳动物中，有六种与NF1高度同源的相关基因 Ras Paralog，分成两个科。我们的研究依赖于跨学科的方法， 包括细胞/小鼠遗传学，以及最新的生物化学和分子生物学 技术，以及我们在临床前试验方面的专业知识。我们的初步数据，由新的 试剂和技术支持规范RAS蛋白在NF1突变体中的关键作用 雪旺细胞增殖。我们现在将评估RAS蛋白在原发疾病中的具体作用 雪旺细胞在体外，在神经纤维瘤体内，并测试一种潜在的靶向治疗 活着。重要的是，神经纤维蛋白是否有雪旺细胞特异性的相互作用伙伴 超越RAS的蛋白质是未知的。利用邻近生物素化技术对我们的初步研究 在雪旺细胞中寻找新的潜在的NF1-相互作用伙伴。我们将确定建筑群 含有神经纤维蛋白和这些蛋白以及特定的RAS类似物，以及其他 细胞刺激时可能形成的复合体，并测试阻断已识别的通路是否有用 从治疗上讲。

Abstract The NF1 gene product, neurofibromin, was identified in 1990, yet fundamental questions remain unanswered concerning its intracellular location(s), binding partners, and signaling properties. It is known that the large (>200kd) tumor suppressor protein contains a small domain that turns of RAS proteins, so that loss of NF1 function leads to RAS activation on cell stimulation. The remaining NF1 sequence can interact with a chaperone, SPRED1, and other proteins in vitro and/or in specific cell types. In Schwan cells, NF1 loss results in formation of neurofibromas, tumors in the peripheral nerves. It is still unknown which interaction partners and RAS proteins are relevant in Schwann cells. Here we propose to identify NF1 interaction partners, including relevant RAS proteins, that contribute to Schwann cell tumorigenesis. This is because in mammals there are six highly homologous NF1-related RAS paralogs, divided into two families. Our studies rely on interdisciplinary approaches, including cell/mouse genetics, and state of the art biochemical and molecular biology techniques, and our expertise in preclinical testing. Our preliminary data, enabled by new reagents and technologies, supports key roles for canonical RAS proteins in NF1 mutant Schwann cell proliferation. We will now assess the specific roles of RAS proteins in primary Schwann cells in vitro, and in neurofibroma in vivo, and test a potential targeted therapy in vivo. Importantly, whether neurofibromin has Schwann cell-specific interaction partners beyond RAS proteins is unknown. Using proximity biotinylation our preliminary studies identify novel potential NF1-interaction partners in Schwann cells. We will identify complexes containing neurofibromin and these proteins and specific RAS paralogs, and additional complexes that may form on cell stimulation, and test if blocking identified pathways is useful therapeutically.