EXPRESSION/REGULATION OF PHOSPHODIESTERASE 3 ISOFORMS

磷酸二酯酶 3 异构体的表达/调节

• 批准号: 6162715
• 负责人: V MANGANIELLO
• 金额: --
• 依托单位: NATIONAL HEART, LUNG, AND BLOOD INSTITUTE
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/6162715
• 关键词: 3'5' cyclic nucleotide phosphodiesterase; B lymphocyte; T lymphocyte; cell differentiation; cell type; enzyme activity; esterase inhibitor; gene targeting; in situ hybridization; inflammation; isozymes; laboratory mouse; laboratory rat; leukocyte activation /transformation; macrophage; natural killer cells; northern blottings; protein isoforms; transfection

By catalyzing hydrolysis of cAMP and cGMP, cyclic nucleotide phosphodiesterases (PDEs) are critical regulators of intracellular concentrations of, and biological responses mediated by, cyclic nucleotides, including immune/in- flammatory responses. Understanding cellular regulation of PDE isoforms [which belong to seven gene families (PDE1-7)] will be of increasing importance for targeting specific PDEs in treating pulmonary disorders. Although individual cells usually contain representatives of several PDE gene families, little is known of signalling pathways involved in cytokine and growth factor regulation of different PDEs in a single cell. Incubation of FDCP-2 myeloid cells with Interleukin-4 (IL-4) increased both PDE3 and PDE4 activities, whereas IL-3, Granulocyte/Macrophage Colony Stimulating Factor (GMCSF) and phorbol ester (PMA) increased PDE4 only. IL-4 (not IL-3, GMCSF, PMA) induced rapid tyrosine phosphorylation of Insulin-receptor Substrate-2 (IRS-2 is a docking protein which functions to localize and coordinate interactions between receptors and signalling molecules/complexes). IL-4 induced activation of PDE3, PDE4 and the downstream protein kinases, mitogen-activated kinase (MAPK) and PKB, (but not IL-4 induced phosphorylation of STAT-5) were blocked by Tumor Necrosis Factor alpha (TNFalpha) which reduced IL-4-induced tyrosine phosphorylation of IRS-2 and its association with phosphatidylinositol 3-kinase (PI3-K) and by wortmannin, a PI3-K inhibitor. Downstream of PI3-K, IL-4 signals diverge, with PDE3 regulated by MAPK-independent and PDE4 by MAPK-dependent pathways. IL-3, GMCSF, and PMA also regulate PDE4 by MAPK dependent pathways. Whereas IL-3 induced activation of MAPK may be mediated by PI3-K (independent of IRS-2 signals) the effect of PMA is dependent on Protein kinase C signals. Thus, PDE4 may be regulated by MAPK activated by different mechanisms, i.e., IRS-2/PI3-K (IL-4), PI3-K ( IL-3, GMCSF) and Protein kinase C (PMA). It is possible that IRS-2 is intimately involved in IL-4 induced activation of PDE3, perhaps by initiating a specific set of signals or by targeting a specific signalling complex to PDE3. Although PDE4 is thought to be the predominant PDE isoform in most inflammatory/immune cells, PDE3 and PDE4, which exhibit a high affinity for cAMP, are both present in lymphocytes and macrophages. However, the proportion of PDE4 relative to PDE3 was greater in T-cells infected with the human T-cell leukemia/lymphotropic virus Type I (HTLV-1) than in other T cell-derived cells, including cells infected with the related retrovirus HTLV-2, NK lymphocytes, Kit and Jurkat leukemia cell lines, CD4+ T-cell clones specific sensitized to myelin basic protein. Incubation of some, but not all, HTLV-1 infected cell lines with the scr-kinase inhibitor herbimycin dramatically reduced PDE activity; the mechanism(s) and significance of this differential inhibition by herbimycin is not understood. After 5-7 days in culture elutriated peripheral human monocytes adhere to plastic surfaces and increase dramatically in size. The morphologic change is accompanied by a relative increase in PDE3B mRNA and activity, Glut 5 transporter and PDE1C mRNAs and a relative decrease in PDE4 activity and PDE4B mRNA. It will be important to define specific PDE isoforms present in alveolar macrophages and to determine if cellular inflammatory responses can be altered by PDE inhibitors.

通过催化CAMP和CGMP的水解，环状核苷酸 磷酸二酯酶（PDE）是细胞内的关键调节剂 循环介导的浓度和生物反应的浓度和生物反应 核苷酸，包括免疫/燃料反应。 理解 PDE同工型的细胞调节[属于七个基因家族 （PDE1-7）]对靶向特定PDE的重要性将增加 治疗肺部疾病。 尽管单个细胞通常 包含几个PDE基因家族的代表，鲜为人知 涉及细胞因子和生长因子调节的信号通路 单个单元格中不同的PDE。 孵育FDCP-2髓样细胞 随着白介素-4（IL-4）的增加，PDE3和PDE4活性都增加了， 而IL-3，粒细胞/巨噬细胞刺激因子（GMCSF） 和佛波酯（PMA）仅增加PDE4。 IL-4（不是IL-3，GMCSF，PMA） 胰岛素受体底物-2的诱导快速酪氨酸磷酸化 （IRS-2是一种对接蛋白，其作用可定位和坐标 受体与信号分子/复合物之间的相互作用）。 IL-4诱导的PDE3，PDE4和下游蛋白的激活 激酶，有丝分裂原激活激酶（MAPK）和PKB（但未诱导IL-4 Stat-5的磷酸化被肿瘤坏死因子alpha阻断 （tnfalpha）降低了IRS-2的IL-4诱导的酪氨酸磷酸化 及其与磷脂酰肌醇3-激酶（PI3-K）的关联 Wortmannin，PI3-K抑制剂。 PI3-K，IL-4信号的下游 分歧，由由MAPK独立和PDE4调节的PDE3由 MAPK依赖性途径。 IL-3，GMCSF和PMA也通过 MAPK依赖途径。 而IL-3诱导的MAPK激活可能 由PI3-K（独立于IRS-2信号）介导PMA的效果 取决于蛋白激酶C信号。因此，可以调节PDE4 由MAPK被不同的机制激活，即IRS-2/PI3-K（IL-4）， PI3-K（IL-3，GMCSF）和蛋白激酶C（PMA）。 有可能 IRS-2与IL-4诱导的PDE3激活密切相关，也许 通过启动一组特定的信号或针对特定的信号 信号复合物至PDE3。 虽然PDE4被认为是 在大多数炎症/免疫细胞中，PDE3和PDE3和 对营地表现出高亲和力的PDE4都存在 淋巴细胞和巨噬细胞。 但是，PDE4相对的比例 在被人类T细胞感染的T细胞中，PDE3更大 与其他T细胞衍生的白血病/淋巴病毒I型（HTLV-1） 细胞，包括感染相关逆转录病毒HTLV-2，NK的细胞 淋巴细胞，套件和Jurkat白血病细胞系，CD4+ T细胞克隆 特异性对髓磷脂碱性蛋白质敏感。 孵化一些，但是 并非全部，HTLV-1感染了SCR-激酶抑制剂的细胞系 除草霉素大大降低了PDE活性；机制和 除草剂抑制这种差异的意义不是 理解。 5-7天后，培养的外围人类 单核细胞粘附在塑料表面并大小急剧增加。 形态变化伴随着PDE3B的相对增加 mRNA和活性，Glut 5转运蛋白和PDE1C mRNA以及相对 PDE4活性和PDE4B mRNA的降低。 重要的是 定义肺泡巨噬细胞中存在的特定PDE同工型 确定PDE是否可以改变细胞炎症反应 抑制剂。