PKC zeta as a Target for Ceramide

PKC zeta 作为神经酰胺的靶标

• 批准号: 7148916
• 负责人: MARK KESTER
• 金额: $ 36.51万
• 依托单位: PENNSYLVANIA STATE UNIV HERSHEY MED CTR
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-08-01 至 2011-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7148916
• 关键词: JUN kinase; X ray crystallography; angiogenesis; binding sites; biophysics; cell growth regulation; cell line; ceramides; enzyme activity; enzyme induction /repression; inflammation; intraluminal angioplasty; laboratory mouse; lipid raft; molecular dynamics; nuclear magnetic resonance spectroscopy; postoperative complications; protein kinase C; protein localization; protein protein interaction; second messengers; serine threonine protein kinase; site directed mutagenesis; surface plasmon resonance; vascular smooth muscle

DESCRIPTION (provided by applicant): Ceramide is a lipid-derived second messenger that suppresses vascular smooth muscle (VSM) cell mitogenesis in vitro and in vivo. Multiple laboratories, including our own, have identified protein kinase C zeta (PKCzeta) as a target of ceramide. We have published data demonstrating that ceramide-activated PKCzeta is necessary for VSM cell growth arrest. Two signaling pathways have been identified that contribute to the anti-mitogenic actions of ceramide. Ceramide directly activates PKCzeta, to 1.) induce SAPK signal complex formation; and 2.) inhibit AKT1 signaling cascades. Elucidation of the biophysical and biochemical mechanisms by which ceramide activates PKCzeta is the focus of this new proposal. It is now hypothesized that ceramide stimulates PKCzeta; activity within discrete lipid microdomains or rafts. We will test this hypothesis in the following Specific Aims. In Specific Aim 1, we will identify ceramide-enriched lipid rafts as the site at which PKCzeta, is phosphorylated and optimally activated by upstream kinases. In Specific Aim 2, we will characterize and validate ceramide-binding domains or clefts on PKCzeta. These studies will elucidate the biophysical and biochemical mechanisms by which inflammatory cytokine receptor-induced ceramide formation limits cellular proliferation in models of inflammatory vascular diseases. The long-term innovation of these studies is the clinical potential of direct delivery of ceramide analogues to the site of dysregulated VSM growth observed after angioplasty and stent placement. Additionally, this proposal holds the promise of defining lipidomimetics suitable as therapeutics or screening tools for further drug discovery.

描述（由申请人提供）： 神经酰胺是脂质衍生的第二信使，可在体外和体内抑制血管平滑肌（VSM）细胞有丝分裂发生。包括我们自己在内的多个实验室已经将蛋白激酶C Zeta（Pkczeta）鉴定为神经酰胺的靶标。我们已经发布了数据，证明了神经酰胺激活的PKCZETA对于VSM细胞生长停滞是必需的。已经确定了两个信号通路，这些信号通路有助于神经酰胺的抗裂化作用。神经酰胺直接激活Pkczeta，至1。）诱导SAPK信号复合物的形成；和2.）抑制AKT1信号级联。阐明神经酰胺激活Pkczeta的生物物理和生化机制是该新建议的重点。现在假设神经酰胺会刺激pkczeta。离散脂质微区或筏子内的活性。我们将在以下特定目标中检验这一假设。在特定的目标1中，我们将识别富含神经酰胺的脂质筏作为pkczeta的位置，被上游激酶磷酸化并最佳地激活。在特定的目标2中，我们将表征和验证pkczeta上的神经酰胺结合域或裂缝。这些研究将阐明炎性细胞因子受体诱导的神经酰胺形成的生物物理和生化机制限制了炎性血管疾病模型中的细胞增殖。这些研究的长期创新是将神经酰胺类似物直接传递到血管成形术和支架放置后观察到的失调VSM生长部位的临床潜力。此外，该提案有望定义适合于进一步药物发现的治疗或筛查工具的脂质仪。