Protein Phosphatase 1 Holoenzyme Formation

蛋白磷酸酶 1 全酶形成

• 批准号: 10671729
• 负责人: Wolfgang Peti
• 金额: $ 38.72万
• 依托单位: UNIVERSITY OF CONNECTICUT SCH OF MED/DNT
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-08-01 至 2026-07-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10671729
• 关键词: ATP phosphohydrolase; Area; Binding; Biochemical; Biogenesis; Biological; Biological Process; Biology; Biophysics; Cells; Cellular biology; Complex; Cysteine; Data; Development; Disease; Dissociation; Drug Targeting; Enzymes; Essential Genes; Eukaryota; Eukaryotic Cell; Excision; Genetic; Goals; Health; Holoenzymes; Hydrolysis; Individual; Laboratories; Location; Malignant Neoplasms; Metals; Mitosis; Molecular; Molecular Chaperones; Phosphoric Monoester Hydrolases; Phosphorylation; Phosphotransferases; Post-Translational Protein Processing; Protein Deficiency; Protein Dephosphorylation; Protein Inhibition; Protein phosphatase; Proteins; Reaction; Regulation; Research; Research Personnel; Research Project Grants; Role; Serine/Threonine Phosphorylation; Signal Transduction; Structure; Substrate Specificity; Testing; Threonine Phosphorylation Site; Work; Yeasts; biophysical tools; cell growth; dimer; experimental study; human disease; inhibitor; inorganic phosphate; insight; novel; novel strategies; protein phosphatase inhibitor-1; response; structural biology; tool; ubiquitin-protein ligase; yeast genetics

ABSTRACT Phosphorylation is one of the most ubiquitous, reversible posttranslational modifications in cells. The enzymes responsible for controlling the phosphorylation state of the cell are kinases, which catalyze the transfer of the γ-phosphate moiety of ATP to substrates, and phosphatases, which catalyze the reverse hydrolysis reaction, the removal of the phosphate moiety from phosphorylated substrates. Thus, phosphatases dynamically reverse the effects of kinases. Because phosphorylation is critical for all biological processes from cell growth to differentiation to development, the location and duration of the reciprocal actions of kinases and phosphatases must be exquisitely regulated both temporally and spatially within the cell. Consequently, when this tight regulation is disrupted, dysregulation of phosphorylation signaling ensues and the consequence is most often disease. Deletion of either one of two PP1 regulators—SDS22 (PPP1R7) or Inhibitor-3 (I3; PPP1R11 or Ypi1 in yeast)—is lethal in yeast (essential genes), highlighting their biological significance. However, since their discovery, different biological roles have been assigned to SDS22 and I3, including roles in mitosis (SDS22), E3 ligase functionality (I3), PP1 biogenesis, among others. Thus, while it is clear that SDS22 and I3 are essential PP1 regulators, their true biological function(s) and especially their mechanism(s) of action are still unknown. This has hindered progress in understanding their roles in PP1 biology. In cells, these proteins form both heterodimeric (SDS22:PP1 and I3:PP1) and a heterotrimeric (SDS22:I3:PP1; SIP) PP1 complex. The structure and function(s) of the individual dimeric complexes, if and how the structure and function(s) of the trimeric complex differs from those of the dimeric complexes and the role(s) of each complex in PP1 holoenzyme formation are major questions in the field. Further, additional data suggest that dissociation of the SIP complex requires the AAA+ ATPase p37/p97. However, the molecular details of SIP complex dissociation have also remained elusive. The presented research project uses a powerful integrated approach that combines structural biology with biochemical and cell biology experiments to obtain novel insights into the molecular mechanisms used by these regulators to control PP1 activity and direct PP1 holoenzyme assembly. Because PP1 holoenzymes have critical roles in human diseases, the proposed work will provide novel strategies for selectively inhibiting PP1 activity by targeting the PP1 holoenzyme formation and subunit exchange, which is essential for understanding how distinct PPPs contribute to disease.

抽象的 磷酸化是细胞中最普遍、可逆的翻译后修饰之一。酶 负责控制细胞磷酸化状态的是激酶，它催化磷酸化的转移 ATP 的 γ-磷酸部分与底物和磷酸酶催化逆水解反应， 从磷酸化底物中去除磷酸部分。因此，磷酸酶动态逆转 激酶的作用。因为磷酸化对于从细胞生长到 分化到发育、激酶和磷酸酶相互作用的位置和持续时间 必须在细胞内的时间和空间上受到精确的调节。因此，当如此紧张时 调节被破坏，磷酸化信号传导失调，其后果通常是 疾病。删除两个 PP1 调节因子之一 - SDS22 (PPP1R7) 或 Inhibitor-3 (I3; PPP1R11 或 Ypi1 在酵母中）——在酵母中是致命的（必需基因），突出了它们的生物学意义。然而，由于他们的 发现，不同的生物学作用已被分配给 SDS22 和 I3，包括有丝分裂中的作用 (SDS22)， E3 连接酶功能 (I3)、PP1 生物发生等。因此，虽然很明显 SDS22 和 I3 是 重要的 PP1 调节剂，其真正的生物学功能，特别是其作用机制仍不清楚 未知。这阻碍了理解它们在 PP1 生物学中的作用的进展。在细胞中，这些蛋白质形成 异二聚体（SDS22:PP1 和 I3:PP1）和异三聚体（SDS22:I3:PP1；SIP）PP1 复合物。这 各个二聚体复合物的结构和功能，是否以及如何确定其结构和功能 三聚体复合物与二聚体复合物不同，并且每个复合物在 PP1 中的作用不同 全酶的形成是该领域的主要问题。此外，额外的数据表明，解离 SIP 复合物需要 AAA+ ATP 酶 p37/p97。然而，SIP 复合物解离的分子细节 也一直难以捉摸。所提出的研究项目使用了一种强大的综合方法， 将结构生物学与生化和细胞生物学实验相结合，以获得对结构生物学的新见解 这些调节剂用于控制 PP1 活性和指导 PP1 全酶组装的分子机制。 由于 PP1 全酶在人类疾病中具有关键作用，因此拟议的工作将为 通过靶向 PP1 全酶形成和亚基选择性抑制 PP1 活性的策略 交换，这对于理解不同的 PPP 如何导致疾病至关重要。