Interaction between I region loci influences the expression of a cell surface Ia antigen.
Interaction between I region loci influences the expression of a cell surface Ia antigen.
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I 区基因座之间的相互作用影响细胞表面 Ia 抗原的表达。
DOI：
10.1073/pnas.77.9.5404
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发表时间：
1980
影响因子：
11.1
通讯作者：
McDevitt,HO
中科院分区：
文献类型：
--
作者：
Murphy,DB;Jones,PP;Loken,MR;McDevitt,HO
聚集在小鼠H-2基因复合体I区的基因座控制着对外来抗原产生免疫应答的能力（Ir基因座），并控制分化抗原，分化抗原似乎是细胞相互作用和调节的结构（Ia基因座）。遗传学和功能研究表明，Ia抗原可能是Ir位点的产物。最近的研究表明，紧密相连的Ir位点之间的相互作用是产生对某些外来抗原的免疫反应所必需的，而h -2连接的位点之间的相互作用决定了淋巴细胞细胞表面Ia糖蛋白（Ae链）的出现。在本报告中，我们发现一个Ia基因座调控另一个Ia基因座的产物（E α链）的定量表达。该调控位点在顺式或反式染色体位置上主要表达并发挥其作用。因此，一些Ia产物的定量和定性表达依赖于紧密连接位点之间的相互作用。我们的研究结果提示了这种调节的可能的分子基础：Ae和E α链的合成和细胞内结合可能是淋巴细胞细胞表面正常水平表达的绝对需要。这些发现对I区控制免疫反应和人HLA-D抗原研究的意义进行了讨论。
Loci clustered in the I region of the murine H-2 gene complex control the capacity to generate an immune response against foreign antigens (Ir loci) and control differentiation antigens which appear to serve as structures used by cells to interact with and regulate one another (Ia loci). Both genetic and functional studies suggest that Ia antigens may be products of Ir loci. Recent studies have shown that interaction between closely linked Ir loci is required for generating immune responses to certain foreign antigens, and that interaction between H-2-linked loci determines the appearance of an Ia glycoprotein (the Ae chain) on lymphocyte cell surfaces. In this report, we show that one Ia locus regulates the quantitative expression of the product (the E alpha chain) of a second Ia locus. This regulatory locus is dominantly expressed and exerts its effects in either the cis or trans chromosomal position. Thus, the quantitative as well as the qualitative expression of some Ia products is dependent on interaction between tightly linked loci. Our results suggest a possible molecular basis for this regulation: the synthesis and intracellular association of Ae and E alpha chains may be an absolute requirement for the expression of normal levels of either polypeptide chain on the lymphocyte cell surface. The implications these findings have for I region control of immune responses and study of human HLA-D antigens are discussed.