KAPPA GENE REARRANGEMENT IN TRANSFORMED PREB CELLS

免疫球蛋白基因重排是骨肉瘤发生发展的基础 淋巴细胞。了解这些细胞的产生以及通过 它们所获得的特定抗原受体仍然是 免疫学中的问题。Abelson病毒转化的前B细胞已被 对于研究控制分子事件非常有用 免疫球蛋白基因重排。尽管这种方法很强大， 该模型缺少的一个重要特征是： 以可预测和可预测的方式操纵细胞的分化 可控的时尚。我们通过使用前B细胞克服了这一障碍 用温度敏感型Abelson病毒转化。当这些细胞 都是在不允许的温度下孵化的轻链基因 重排在一到一年内的高百分比细胞中被激活 四天。 我们将使用温度敏感的Pre-B转化子来询问三个 问题。1.前B细胞向B细胞的转变是否发生在 温度敏感转化子及其受免疫球蛋白的调节 分子？观察到的轻链重排的高频率 温度敏感的转化子可能反映了这种激活。 单次事件或激活B细胞分化程序。我们会 检测分化标记物的表达以区分它们 两种可能性，并测试免疫球蛋白在 刺激细胞分化。2.kappa的重排 而lambda基因和RS序列是受调控还是随机过程？我们 将使用一系列的时间进程实验来确定 Kappa、lambda和RS的重排在时间上是相关的。这个 转录活性与染色质变化的关系 将检查结构和基因重排。3.什么是基因 在轻链重排过程中表达上调？差异显示将 用于识别在光照时高水平表达的序列 链基因重排被激活。这是一个远景目标 实验是为了识别对轻链很重要的基因 重新编排。

Immunoglobulin gene rearrangement is fundamental to the development of lymphocytes. Understanding the generation of these cells and the means by which they acquire specific antigen receptors remains one of the central issues in immunology. Abelson virus transformed pre-B cells have been extremely useful for investigating the molecular events controlling immunoglobulin gene rearrangement. Despite the power of this approach, one important feature has been missing from this model: the ability to manipulate the differentiation of the cells in a predictable and controllable fashion. We have overcome this obstacle by using pre-B cells transformed with temperature sensitive Abelson virus. When these cells are incubated at the nonpermissive temperature, light chain gene rearrangement is activated in a high percentage of the cells within one to four days. We will use the temperature sensitive pre-B transformants to ask three questions. 1. Does the pre-B to B cell transition occur in the temperature sensitive transformants and is it regulated by immunoglobulin molecules? The high frequency of light chain rearrangement observed in the temperature sensitive transformants may reflect activation of this single event or activation of the B cell differentiation program. We will examine expression of differentiation markers to distinguish between these two possibilities and test the role of immunoglobulin proteins in stimulating differentiation of the cells. 2. Are rearrangement of kappa and lambda genes and RS sequences regulated or stochastic processes? We will use a series of time course experiments to determine if rearrangements of kappa, lambda and RS are related temporally. The relationship between transcriptional activity, changes in chromatin structure and gene rearrangement will be examined. 3. What genes are upregulated during light chain rearrangements? Differential display will be used to identify sequences that are expressed at high levels when light chain gene rearrangement is activated. A long range goal of these experiments is to identify genes that are important for light chain rearrangement.