REGULATION OF EXPRESSION OF CLASS I MHC GENE

这项工作的目的是研究控制的机制。 多基因家族的表达。这只微型猪有 被选为实验模型是因为只有7个 家庭成员。要解决分子的问题 调节I类MHC基因表达的两种方法 已采取：1)体内表达模式的分析 每种基因，包括原位基因和转基因小鼠；以及2) 与这些相关的监管要素的特征 基因。 对体内模式的分析表明，无论是共享的还是离散的 监管机制在家庭内部运作。因此，一些基因 是协调表达的，而其他则不是。在这两种情况下， 表达模式受到积极的调控。 一种移植抗原内的调节序列 基因是通过产生一系列5‘端来识别的 缺失突变体。一系列积极和消极的因素 已经被映射了。一种新的负向调节元件，其 需要存在积极的元素才能发挥作用， 已经被确认了。已经进一步证明，这些 这些元素通过反式作用因子的结合发挥作用。这个 反式作用因子的结合部位已经用 凝胶滞留分析和核酸外切酶保护。

The aim of this work is to investigate the mechanisms controlling the expression of a multi-gene family. The miniature swine has been chosen as an experimental model because there are only 7 members of the family. To address the question of the molecular regulation of the expression of class I MHC genes, two approaches have been taken: 1) the analysis of in vivo patterns of expression of each of the genes, both in situ and in transgenic mice; and 2) characterization of regulatory elements associated with these genes. Analysis of in vivo patterns reveals that both shared and discrete regulatory mechanisms operate within the family. Thus, some genes are coordinately expressed, whereas others are not. In both cases, patterns of expression are actively regulated. Regulatory sequences within one of the transplantation antigen genes have been identified by generating a series of 5' end deletion mutants. A series of both positive and negative elements have been mapped. A novel negative regulatory element, which requires the presence of a positive element in order to function, has been identified. It has been further demonstrated that these elements function through the binding of tran sacting factors. The binding sites of the trans acting factors have been mapped using both gel retardation assays and exonuclease protection.