Control of Protein Synthesis by the UPS Under Stress

项目总结 这一建议是基于新发现的细胞应激反应的调节臂，由此Jun N- 末端激酶(JNK)被招募来翻译核糖体(多聚体)，以介导新的 合成蛋白质(NSP)。我们确定了这个新的调控模块对乳腺癌的意义。 (BCA)生物学，并识别首次连接的泛素蛋白酶体系统(UPS)组件 在国家体育总局的监督下。它们包括cullin 2、Nedd8和ubiquilin1(UBQLN1)，我们演示了它们 影响BCA细胞的蛋白质合成。这些UPS成分在BCA中的异常表达 研究它们在BCA发展和治疗反应中的作用的理论基础。 我们的初步结果支持这样的假设，即对NSP稳定性的控制构成了一层新的 调节蛋白质的合成/可获得性，进而控制细胞对应激的反应。我们 进一步假设，这种监管对BCA的发展和应对具有直接影响 心理治疗。我们的重点是几个互补的，但到目前为止还没有得到认可的机制，它们可能是NSP的基础 处于压力下的监视。 Topisirovic博士、Sonenberg博士、Mills博士和Ronai博士之间富有成效的长期合作是 现已扩展到包括Meller博士，从而在以下领域实现了广泛和互补的专业知识 蛋白质合成和癌症生物学还包括纳米孔传感技术，使解决 泛素链拓扑。我们将共同评估具体的、新确定的NSP监管因素 单独或共同发挥调节细胞应激反应的功能，特别是在BCA的背景下 发展和对治疗的反应。建议的研究将：(1)建立生理学 RACK1-JNK-eEF1A2调节轴在细胞应激反应、生长和发育中的意义 乳腺癌的治疗反应。(2)评估应激诱导的多核体招募的作用。 NEDD8-cullin机制在调节BCA中NSP衰变中的作用(三)确定工作重点 UBQLN1在应激条件下调节新合成蛋白质的多聚体募集 以及调节BCA对治疗的反应。 我们提出的研究将确定在一部小说中选择UPS组件的重要性和意义 在细胞应激期间控制蛋白质合成的调控网络，并通过使用 BCA培养和异种移植的结合、RPPA技术和TCGA数据集挖掘。

PROJECT SUMMARY This proposal is based on a newly discovered regulatory arm of the cellular stress response, whereby Jun N- terminal kinase (JNK) is recruited to translating ribosomes (polysomes) to mediate degradation of newly synthesized proteins (NSPs). We established the significance of this novel regulatory module to breast cancer (BCa) biology, and identify ubiquitin proteasome system (UPS) components that—for the first time—are linked with the surveillance of NSPs. They include Cullin 2, Nedd8, and ubiquilin1 (UBQLN1), which we demonstrate to impact protein synthesis in BCa cells. Dysregulated expression of these UPS components in BCa underlies the rationale for studying their role in BCa development and response to therapy. Our preliminary results support the hypothesis that control of NSP stability constitutes a novel layer of regulation of protein synthesis/availability, which in turn governs cellular responses to stress. We further hypothesize that such regulation has direct implications for BCa development and response to therapy. We focus on several complementary but hitherto unappreciated mechanisms that may underlie NSP surveillance under stress. The productive and long-standing collaborations between Drs. Topisirovic, Sonenberg, Mills and Ronai are now extended to include Dr. Meller, thereby enabling extensive and complementary expertise in the areas of protein synthesis and cancer biology to also include nanopore-sensing technology, enabling the resolution of ubiquitin chain topologies. Together, we will assess specific, newly identified NSP regulatory factors that function individually or in concert to regulate the cellular stress response, particularly in the context of BCa development and response to therapy. The proposed research will: (1) Establish the physiological significance of the RACK1–JNK–eEF1A2 regulatory axis to the cellular stress response, growth and therapeutic response of breast cancer. (2) Assess the role of stress-induced polysomal recruitment of Nedd8–Cullin machinery in regulating the decay of NSPs in BCa. (3) Determine the importance of UBQLN1 recruitment to polysomes in regulating newly synthesized proteins under stress conditions and in modulating the response of BCa to therapy. Our proposed studies will establish the importance and significance of select UPS components in a novel regulatory network that controls protein synthesis during cellular stress, and establish its role in BCa using a combination of BCa cultures and xenografts, RPPA technology, and TCGA dataset mining.