Activation and Regulation Mechanisms of the RAF Kinase Family

RAF激酶家族的激活和调节机制

• 批准号: 10655698
• 负责人: Zhihong Wang
• 金额: $ 17.3万
• 依托单位: ROWAN UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-09-10 至 2025-08-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10655698
• 关键词: Activation; Regulation; Mechanisms; RAF; Kinase

BRAF, a member of the RAF family protein kinases, works in the MAPK signaling pathway, which controls broad cellular events like proliferation and differentiation. BRAF is the most frequently mutated kinase in human cancers. Furthermore, tumors lacking BRAF mutations are contingent on BRAF activity when there are mutations in upstream pathway members, such as RAS or growth factor receptors. Thus, BRAF represents an important target for cancer therapy. Despite three decades of intense research, only recently has a sufficient understanding of BRAF's mechanism creaked open the door to BRAF therapy. However, the current clinical BRAF inhibitors, vemurafenib and dabrafenib, are limited to the class I mutant BRAFV600E. Vemurafenib and dabrafenib, the two ATP-competitive inhibitors, can paradoxically activate non-BRAFV600E and wild-type BRAF, suggesting that BRAF has functions that are independent of its kinase activity. Therapeutic strategies for tumors with non- BRAFV600E mutations and wild-type BRAF are still lacking. Gaps in our knowledge contributed to the limitations of ATP-competitive BRAF drugs. The proposed work centers around three questions regarding RAF activation and regulation in health and disease states. Q1: how BRAF structural elements and ATP binding mediate the catalytic-independent functions of non-BRAFV600E and wild-type BRAF? Q2: what is the mechanism of action of the first BRAF allosteric inhibitor developed by our group and how can inhibitors targeting the catalytic and non- catalytic functions of BRAF be developed? Q3: What factors contribute to the non-overlapping functions of RAF isoforms, despite their structural similarity? The PI and her team will address these questions through multidisciplinary approaches, including X-ray crystallography, binding kinetics, phosphoproteomics, live cell imaging, chemical biology, and computational methods. Our findings will not only facilitate a better understanding of the complex biochemical mechanisms of the RAF kinase family, also provide a molecular basis for novel therapeutic approaches targeting BRAF-driven tumors.

BRAF 是 RAF 家族蛋白激酶的成员，在 MAPK 信号通路中发挥作用，该通路控制广泛的 细胞事件，如增殖和分化。 BRAF 是人类最常见的突变激酶 癌症。此外，缺乏 BRAF 突变的肿瘤在存在突变时取决于 BRAF 活性 上游通路成员，例如 RAS 或生长因子受体。因此，BRAF 代表了一个重要的 癌症治疗的目标。尽管经过了三十年的深入研究，直到最近才有了足够的了解 BRAF 机制的研究开启了 BRAF 疗法的大门。然而，目前临床上的BRAF抑制剂， vemurafenib 和 dabrafenib 仅限于 I 类突变体 BRAFV600E。维莫非尼和达拉非尼这两个 ATP 竞争性抑制剂可以矛盾地激活非 BRAFV600E 和野生型 BRAF，这表明 BRAF 具有与其激酶活性无关的功能。非肿瘤的治疗策略 BRAFV600E突变和野生型BRAF仍然缺乏。我们知识的差距导致了局限性 ATP 竞争性 BRAF 药物。拟议的工作围绕有关 RAF 激活的三个问题 以及健康和疾病状态下的监管。 Q1：BRAF结构元件和ATP结合如何介导 非 BRAFV600E 和野生型 BRAF 的催化独立功能？ Q2：作用机制是什么？ 我们组开发的第一个BRAF变构抑制剂以及针对催化和非催化的抑制剂如何 BRAF的催化功能有待开发吗？ Q3：哪些因素促成了 RAF 职能的不重叠 同工型，尽管它们的结构相似？ PI 和她的团队将通过以下方式解决这些问题 多学科方法，包括 X 射线晶体学、结合动力学、磷酸蛋白质组学、活细胞 成像、化学生物学和计算方法。我们的发现不仅有助于更好地理解 RAF激酶家族复杂的生化机制的研究，也为新的研究提供了分子基础。 针对 BRAF 驱动肿瘤的治疗方法。