Maddon P J, Molineaux S M, Maddon D E, Zimmerman K A, Godfrey M, Alt F W, Chess L, Axel R
Department of Biochemistry and Molecular Biophysics, College of Physicians and Surgeons, Columbia University, New York, NY 10032.
Proc Natl Acad Sci U S A. 1987 Dec;84(24):9155-9. doi: 10.1073/pnas.84.24.9155.
The T4 molecule may serve as a T-cell receptor recognizing molecules on the surface of specific target cells and also serves as the receptor for the human immunodeficiency virus. To define the mechanisms of interaction of T4 with the surface of antigen-presenting cells as well as with human immunodeficiency virus, we have further analyzed the sequence, structure, and expression of the human and mouse T4 genes. T4 consists of an extracellular segment comprised of a leader sequence followed by four tandem variable-joining (VJ)-like domains, a transmembrane domain, and a cytoplasmic segment. The structural domains of the T4 protein deduced from amino acid sequence are precisely reflected in the intron-exon organization of the gene. Analysis of the expression of the T4 gene indicates that T4 RNA is expressed not only in T lymphocytes, but in B cells, macrophages, and granulocytes. T4 is also expressed in a developmentally regulated manner in specific regions of the brain. It is, therefore, possible that T4 plays a more general role in mediating cell recognition events that are not restricted to the cellular immune response.
T4分子可作为识别特定靶细胞表面分子的T细胞受体，同时也是人类免疫缺陷病毒的受体。为了明确T4与抗原呈递细胞表面以及与人类免疫缺陷病毒相互作用的机制，我们进一步分析了人和小鼠T4基因的序列、结构及表达情况。T4由一个细胞外区段组成，该区段包含一个前导序列，其后是四个串联的可变连接（VJ）样结构域、一个跨膜结构域和一个胞质区段。从氨基酸序列推导的T4蛋白的结构域在该基因的内含子-外显子组织中得到了精确体现。对T4基因表达的分析表明，T4 RNA不仅在T淋巴细胞中表达，在B细胞、巨噬细胞和粒细胞中也有表达。T4在大脑的特定区域也以发育调控的方式表达。因此，T4有可能在介导不限于细胞免疫反应的细胞识别事件中发挥更普遍的作用。
