THE EFFECT OF MOLECULAR TOXINS ON PROTEIN PHOSPHATASE 1 TARGETING

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 分子毒素是一种天然产物，能有效抑制蛋白磷酸酶1(PP1)的催化活性。这些天然的抑制物是由海洋海绵和蓝藻等多种生物产生的，包括冈田酸、盏花素A、微囊藻毒素、根瘤菌素、交托霉素和福斯特里菌素。我们希望全面了解这些分子毒素与PP1紧密结合的结构和动力学机制。这将使我们能够表征靶向和抑制蛋白诱导的PP1活性部位与小分子毒素之间的细微分子差异。这些三维分子模型将使我们能够充分了解PP1活性中心结构的细节。为了了解PP1活性位点的动力学及其在分子细节上靶向蛋白质和抑制配体(分子毒素)相互作用的微妙相互作用，我们将使用大量的生化和生物物理技术，特别是核磁共振光谱和X射线结晶学，来阐明许多靶向蛋白质和分子毒素本身以及作为PP1：靶向和PP1：分子毒素复合体的结构。PSP靶向蛋白，如神经元支架蛋白SPIN，将PP1靶向其作用点。目前还不存在这些相互作用的结构模型，也不知道它们是如何受到与分子毒素相互作用的影响的。因此，我们将利用多个PP1：毒素和PP1：靶向结构和动力学之间的异同来确定PP1是如何在细胞中有效和选择性地调节一种普遍存在的丝氨酸/THR磷酸酶，从而开发针对特定群体的磷酸酶(即定位于多巴胺能神经元中的磷酸酶)的新药物。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Molecular toxins are natural products that potently inhibit the catalytic activity of protein phosphatase 1 (PP1). These natural inhibitors are created by numerous organisms such as marine sponges and cyanobacteria and include okadaic acid, calyculin A, microcystins, nodularins, tautomycin and fostriecin. We want to comprehensively understand the structural and dynamical mechanisms of the tight binding of these molecular toxins to PP1. This will enable us to characterize the subtle molecular differences of the PP1 active site induced by targeting and inhibitory proteins versus small molecule molecular toxins. These 3-dimensional molecular models will enable us to fully understand the details of the PP1 active site structure. To understand the PP1 active site dynamics, and its subtle interplay of targeting protein and inhibitory ligand (molecular toxin) interactions in molecular detail, we will use a large portfolio of biochemical and biophysical techniques, especially NMR spectroscopy and X-ray crystallography, to elucidate the structures of numerous targeting proteins and molecular toxins by themselves and as PP1:targeting and PP1:molecular toxin complexes. PSP targeting proteins, such as the neuronal scaffolding protein spinophilin, target PP1 to its point of action. No structural models for these interactions exist, nor is it known how they are affected by interactions with molecular toxins. Thus, we will use the differences and similarities between the multiple PP1:toxin and PP1:targeting structures and dynamics to determine how PP1, a ubiquitous ser/thr phosphatase, is potently and selectively regulated in the cell so that novel agents, which target a particular population of phosphatases (i.e. phosphatases localized in dopaminergic neurons), can be developed.