REGULATION LYMPHOCYTE PROLIFERATION AND DIFFERENTIATION

描述(改编自研究人员摘要)：免疫力减弱 由感染、年龄或基因异常引起的反应会导致 对通常无害的病原体的敏感性。相反，异常激活 免疫反应，例如在自身免疫性疾病中，也是严重的 对健康有害的。因此，在激活和停用之间的平衡 淋巴细胞对人类的健康至关重要。我们的长期目标是 了解达到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。 在这项应用中，我们建议研究核因子-KB蛋白是如何参与 淋巴细胞的激活和失活。具体目标如下：1) 植物生长抑制和细胞质拴系的分子基础研究 激活信号停止时的核因子-kB蛋白。这些研究将 提供对免疫后重新建立休息石板的见解 回应；2)研究支配时间安排的机制 活化诱导T细胞死亡(AICD)。我们将研究这一角色 核因子-kB在AICD细胞中的作用，并在 效应阶段；3)表征Ikba和Ikba的组织特异性修饰 与REL家族成员区别关联的基础。 这些目标将通过生物化学和生物化学的结合来实现 遗传方法。将在酵母中检测核转录因子-KB的核进出口 和哺乳动物细胞使用荧光显微镜；突变酵母菌株，以及 药物抑制剂将被用来研究IKB蛋白在 核因子-kB的胞质滞留和下调。核因子-kB在AICD中的作用 将通过将FasL诱导从诱导死亡中分离出来进行检查。 这些研究还将寻求该药物抑制AICD的机制 己酮可可碱。最后，IK-BA的磷酸化及其对c-Rel的影响 将通过Ikba的突变来分析与P65的关联；推测 激酶和磷酸酶将在体外进行鉴定。

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.