REGULATION LYMPHOCYTE PROLIFERATION AND DIFFERENTIATION

描述（改编自研究者摘要）：免疫减弱 由感染、年龄或遗传异常引起的反应， 对通常无害的病原体的易感性。相反，异常激活 免疫反应，如自身免疫性疾病，也严重 对健康有害。因此，激活和失活之间的平衡， 淋巴细胞对人类健康至关重要。我们长远的目标是 了解实现这种平衡的分子机制，从而 设计合理的策略来干预这些过程。 在本申请中，我们提出研究NF-κ B蛋白如何参与 淋巴细胞活化和失活。具体目标如下：1） 研究了基因表达下调和细胞质束缚的分子基础， 激活信号停止后的NF-κ B蛋白。这些研究将 提供了免疫后休息状态重建的见解， （2）研究控制时间的机制。 活化诱导的T细胞死亡（AICD）。我们将研究 在AICD的引发细胞中的NF-κ B，以及在AICD期间维持细胞活力。 效应期; 3）表征IkBa的组织特异性修饰， 与Rel家族成员差异关联的基础。 这些目标将通过生物化学和 遗传方法。将在酵母中测定NF-κ B的核输入和输出 和哺乳动物细胞使用荧光显微镜;突变酵母菌株， 药理学抑制剂将用于研究IKB蛋白在 胞质滞留和NF-κ B下调。NF-κ B在AICD中的作用 将通过将FasL诱导与死亡诱导解偶联来检查。 这些研究还将寻求药物抑制AICD的机制 戊二酰苯胺最后，IK-Ba的磷酸化及其对c-Rel的影响 将通过IkBa的诱变分析与p65的关联;推定的 将在体外鉴定激酶和磷酸酶。

DESCRIPTION (adapted from investigator's abstract): Attenuation of immune responses, caused by infection, age or genetic abnormality, leads to increased susceptibility to normally harmless pathogens. Conversely, aberrant activation of immune responses, such as in autoimmune diseases, is also severely detrimental to health. Thus, the balance between activation and inactivation of lymphocytes is essential for human well-being. Our long-term objective is to understand the molecular mechanisms that achieve this balance, and thereby design rational strategies to intervene in these processes. In this application we propose to investigate how NF-KB proteins participate in lymphocyte activation and inactivation. The Specific Aims are as follows: 1) to study for the molecular basis of down-regulation and cytoplasmic tethering of NF-kB proteins upon cessation of an activating signal. These studies will provide insights into the re-establishment of a resting slate after an immune response; 2) to study the mechanisms that govern the timing of activation-induced cell death (AICD) in T cells. We will examine the role of NF-KB in priming cells for AICD, and maintaining cell viability during the effector phase; 3) to characterize tissue-specific modifications of IkBa and the basis for differential association with Rel family members. These objectives will be accomplished by a combination of biochemical and genetic methods. Nuclear import and export of NF-KB will be assayed in yeast and mammalian cells using fluorescence microscopy; mutant yeast strains, and pharmacologic inhibitors will be used to study the role of IKB proteins in cytoplasmic retention and down-regulation of NF-kB. The role of NF-KB in AICD will be examined by uncoupling FasL induction from the induction of death. These studies will also seek a mechanism for the inhibition of AICD by the drug pentoxifylline. Lastly, phosphorylation of IK-Ba and its effects on c-Rel versus p65 association will be analyzed by mutagenesis of IkBa; putative kinases and phosphatase will be identified in vitro.