Gascoigne N R
Department of Immunology, Research Institute of Scripps Clinic, La Jolla, California 92037.
J Biol Chem. 1990 Jun 5;265(16):9296-301.
The T cell receptor (TCR) beta-chain is produced in the endoplasmic reticulum where it associates with the TCR alpha-chain and the members of the CD3 complex to form the complete receptor. When the other chains of the complex are not available, the beta-chain is rapidly degraded within the endoplasmic reticulum. When incomplete TCR.CD3 complexes are formed, they are transported through the Golgi apparatus and degraded in lysosomes. In this study, a truncated form of the TCR beta-chain has been made by removal of the transmembrane and cytoplasmic segments. Unlike the normal beta-chain, the truncated molecule is stable and is transported through the Golgi apparatus and secreted. This process occurs at a similar rate in both T and B cells, indicating that it is not affected by the presence or absence of CD3 components. These data suggest that an element in the transmembrane or cytoplasmic region of the beta-chain confers sensitivity to the degradative control mechanisms that regulate TCR expression.
T细胞受体（TCR）β链在内质网中产生，在那里它与TCRα链和CD3复合物的成员结合形成完整的受体。当复合物的其他链不可用时，β链在内质网中迅速降解。当形成不完整的TCR.CD3复合物时，它们通过高尔基体运输并在溶酶体中降解。在本研究中，通过去除跨膜和细胞质区段制备了一种截短形式的TCRβ链。与正常β链不同，截短的分子是稳定的，通过高尔基体运输并分泌。这个过程在T细胞和B细胞中以相似的速率发生，表明它不受CD3组分存在与否的影响。这些数据表明，β链跨膜或细胞质区域中的一个元件赋予了对调节TCR表达的降解控制机制的敏感性。
