MINORITY PREDOCTORAL FELLOWSHIP PROGRAM

自身免疫性疾病是一种具有广泛病因的衰弱性疾病 和影响。对诱发因素知之甚少。的研究 参与人体自身免疫反应的机制很难 因为有许多变量和分支。 然而，小鼠品系Motheaten viable（mev）提供了一个很好的 在分子水平上研究自身免疫的系统。在这些 老鼠，疾病的遗传原因是已知的-一个单一的突变， 编码造血细胞的蛋白酪氨酸磷酸酶的基因， PTP1C。 磷酸酶在介导信号转导中起关键作用 通过细胞-从最表面近端信号到远端 调节基因表达的转录因子的激活。我有 发现转录因子NFkB异常表达， 在mev免疫细胞中，NFkB的反式激活亚基p65不是 发现-仅检测到p50和CREL。细胞质抑制剂 NFkB，IkB，在mev免疫细胞中也检测不到。这些发现 这是一个新的，以前没有描述过。 为了更仔细地检查 负责这些蛋白质异常表达的机制， 将进行北方印迹以确定这些基因的mRNA是否 蛋白质被转录。在进一步的步骤中， NFkB/IkB蛋白和细胞核中新生mRNA的产生将被抑制。 评估。为了将PTP 1C的作用与异常表达的 NFkB/IkB蛋白，PTP 1C的转录将被阻断或减少， 使用反义技术，在正常表达NF κ B/κ B的B细胞中， 并测定对NFkB/IkB调节的影响。 审查 突变型PTP 1C在mev细胞中的作用，并定义信号 这些细胞将被激活与一些转导途径， 刺激，通过不同模式发出信号，以及对 评估NFkB/IkB表达。长期目标是定义一个模型 用于在自身免疫B细胞中诱导NF κ B，并利用其靶向 潜在的治疗，如采用反义技术，以减少 表达NF κ B，减轻炎症反应。

Autoimmune diseases are debilitating disorders with wide ranges of causes and effects. Little is known about predisposing factors. A study of the mechanisms involved in an autoimmune response in humans is difficult to accomplish because of the multitude of variables and ramifications. However, the mouse strain, motheaten viable (mev), offers an excellent system in which to study autoimmunity at a molecular level. In these mice, the genetic cause for disease is known - a single mutation in a gene encoding a protein tyrosine phosphatase of hematopoietic cells, PTP1C. Phosphatases play critical roles in mediating signal transduction through a cell - from the most surface proximal signals to distal activation of transcription factors that regulate gene expression. I have discovered that the transcription factor, NFkB, is aberrantly expressed in mev immune cells; the transactivating subunit of NFkB, p65, is not found - only p50 and crel are detected. The cytoplasmic inhibitor of NFkB, IkB, is also not detectable in mev immune cells. These findings are novel and have not been previously described. To more closely examine the mechanisms responsible for the aberrant expression of these proteins, northern blots will be performed to determine whether mRNAs for these proteins are transcribed. In further steps, the degradation rates of NFkB/IkB proteins and nascent mRNA production in the nucleus will be evaluated. To correlate the role of PTP1C with the expression of aberrant NFkB/IkB proteins, transcription of PTP1C will be blocked or reduced, using antisense technology, in B cells which normally express NFkB/lkB, and the resulting effects on NFkB/IkB regulation assayed. To examine the effects of the mutant PTP1C in mev cells and define the signal transduction pathways, these cells will be activated with a number of stimuli, that transduce signals via different modes, and the effects on NFkB/IkB expression evaluated. Long term objectives are to define a model for induction of NFkB in autoimmune B cells and use this to target potential therapies such as employing antisense technology to reduce the expression of NFkB and alleviate the inflammatory response.