REGULATION OF RECEPTORS ON T LYMPHOCYTES

描述：森博士的长期目标是在分子水平上 平衡T细胞分化的顺序步骤。森博士 建议识别调控的关键转录因子 阶段特异性基因表达提供了一种重要的机制 检查分化过程。T细胞的调节 受体β链基因和CD8α链基因将 双阴性和双阴性基因表达的探针研究 T细胞发育的阳性阶段。具体目标 这一应用的主要内容是：1)研究其生物学功能 对Jβ2-Cβ2内含子中一个启动子的调控。 有人认为该启动子可能调节TCRβ重排， 这将通过删除胚胎干细胞中的启动子来进行研究 细胞。关键的启动子因子将通过转染法确定， 诱变和体外结合研究。2)识别 在双阴性T-T中激活TCRβ增强子的因素 细胞。将确定核心增强剂并进行差异化阶段 将确定与这些序列相互作用的特定因素 通过比较突变小鼠和分期胎儿的提取物 胸腺细胞。3)CD8α基因调控基因的定义和特征 元素。转基因小鼠将被用来识别 作为基因座控制功能的DNAase I超敏感部位 区域，并赋予发展适当的规则。这个 基因和生化联合实验有望识别出 对胸腺中的发育线索做出反应的因子， 从而为T细胞的操控提供靶点 差异化。

DESCRIPTION: Dr. Sen's long term goal is to understand at a molecular level the sequential steps of T-cell differentiation. Dr. Sen proposes that identification of key transcription factors that regulate stage-specific gene expression provides an important mechanism to examine the differentiation process. The regulation of the T-cell receptor beta chain gene and the CD8 alpha chain gene will be studied as probes of gene expression in double negative and double positive stages of T-cell development, respectively. The Specific Aims of this application are: 1) To study the biological function and regulation of a promoter identified in the J beta 2-C beta 2 intron. It is proposed that this promoter may regulate TCR beta rearrangements, which will be investigated by deleting the promoter in embryonic stem cells. Critical promoter factors will be identified by transfection, mutagenesis and in vitro binding studies. 2) To identify the factors that activate the TCR beta enhancer in double negative T- cells. A core enhancer will be defined and differentiation stage specific factors that interact with these sequences will be identified by comparing extracts from mutant mice and staged fetal thymocytes. 3) To define and characterize CD8 alpha gene regulatory elements. Transgenic mice will be used to identify combinations of DNAase I hypersensitive sites that function as a locus control region and confer developmentally appropriate regulation. The combined genetic and biochemical experiments are expected to identify factors that respond to developmental cues in the thymus and, thereby, provide targets for the manipulation of T- cell differentiation.