EXPRESSION/REGULATION OF PHOSPHODIESTERASE 3 ISOFORMS

磷酸二酯酶 3 异构体的表达/调节

• 批准号: 2576804
• 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/2576804
• 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

One question regarding PDEs relates to cell-specific expression, regulation and function of specific PDE isoforms. Distinct distributions of rat PD3A and B mRNAs were observed in Northern Blots and in situ hybridization. PDE3 isoforms have a limited distribution in human immune/inflammatory cells. cDNA cloning (human lymphocyte cDNA library) and RT-PCR amplification identified PDE3B, not PDE3A, mRNA in T- lymphocytes and peripheral macrophages. T-lymphocytes and macrophages also contain PDE4. Individual T-lymphocyte clones sensitized to basic myelin protein contain different proportions of PDE3 and PDE4 activities (measured with 0.1 uM cAMP) which increase during antigen- stimulated proliferation. The proliferative response is inhibited by specific inhibitors of PDE3 (cilostamide) and PDE4 (rolipram), consistent with the known effects of cAMP on immune/inflammatory cell functions. PDE3 activity was much lower relative to that of PDE4 in EB virus transformed beta-lymphocytes than in T-lymphocytes, NK cells and macrophages. Other workers have reported little or no PDE3 activity in polymorphonuclear leukocytes, eosinophils, basophils, monocytes. In peripheral macrophages PDE3 activity > PDE4; in two mononuclear cell lines, PDE3 > 4 in THP-1 cells and PDE4 >> PDE3 in U937 cells. It is possible that PDE3 activity increases during monocyte/macrophage differentiation. PDE3A isoforms are present in platelets and HEL erythroleukemia cells; by in situ hybridization, rat PDE3A, not B, mRNA was detected in megakaryocytes present in developing liver. The mechanisms for and functional consequences of this differential distribution/expression of PDE3A and B isoforms in immune/inflammatory cells and megakaryocytes/platelets is not known. Understanding of cellular regulation of specific PDE isoforms will be of increasing importance for understanding pathophysiology and for targeting specific PDEs in treatment of pulmonary disorders, especially those relating to inflammation, allergy, and airway and vascular reactivity. To learn more about PDE3B function both during development and in differentiated cells, we are attempting to "knockout" the mouse PDE3B by homologous recombination.

关于 PDE 的一个问题与细胞特异性表达有关， 特定 PDE 同工型的调节和功能。 不同的分布 在 Northern Blots 和原位杂交中观察到大鼠 PD3A 和 B mRNA 的变化 杂交。 PDE3 亚型在人类中的分布有限 免疫/炎症细胞。 cDNA克隆（人淋巴细胞cDNA文库） RT-PCR 扩增鉴定出 T- 中的 mRNA 是 PDE3B，而不是 PDE3A。 淋巴细胞和外周巨噬细胞。 T 淋巴细胞和巨噬细胞 还含有PDE4。 对碱性敏感的单个 T 淋巴细胞克隆 髓鞘蛋白含有不同比例的 PDE3 和 PDE4 活性 （用 0.1 uM cAMP 测量）在抗原刺激期间增加 增殖。 增殖反应受到特定的抑制 PDE3（西洛酰胺）和 PDE4（咯利普兰）抑制剂，与 cAMP 对免疫/炎症细胞功能的已知影响。 偏二苯醚3 EB病毒转化后的活性比PDE4低得多 β 淋巴细胞高于 T 淋巴细胞、NK 细胞和巨噬细胞。 其他 工作人员报告多形核中 PDE3 活性很少或没有 白细胞、嗜酸性粒细胞、嗜碱性粒细胞、单核细胞。 在外周巨噬细胞中 PDE3 活性 > PDE4；在两个单核细胞系中，THP-1 中 PDE3 > 4 细胞和 U937 细胞中的 PDE4 >> PDE3。 PDE3 活性可能 单核细胞/巨噬细胞分化期间增加。 PDE3A 亚型是 存在于血小板和 HEL 红白血病细胞中；就地 杂交，大鼠 PDE3A，而非 B，在巨核细胞中检测到 mRNA 存在于发育中的肝脏中。 机制和功能 PDE3A 的这种差异分布/表达的后果 免疫/炎症细胞和巨核细胞/血小板中的 B 同种型是 不知道。了解特定 PDE 亚型的细胞调节 对于理解病理生理学和 用于针对治疗肺部疾病的特定 PDE， 尤其是那些与炎症、过敏和气道有关的 血管反应性。 要了解有关 PDE3B 功能的更多信息，请在 在发育和分化细胞中，我们正在尝试“敲除” 通过同源重组小鼠 PDE3B。