Takaki K, Polack A, Bornkamm G W
Proc Natl Acad Sci U S A. 1984 Jul;81(14):4568-72. doi: 10.1073/pnas.81.14.4568.
Expression of Epstein-Barr virus (EBV) antigens was studied after transfection of cloned EBV DNA fragments into baby hamster kidney (BHK) cells. A set of seven widely overlapping clones covering the whole genome of the non-defective Epstein-Barr virus strain M-ABA was used for transfection. Transfer of the cosmid clones into BHK cells resulted in expression of two distinct antigens, as revealed by indirect immunofluorescence using human anti-EBV sera. Staining with human sera of different reactivity against EBV-associated antigens revealed that both types of antigens were related to the early antigen complex. The first type of antigen was detected only in the nuclei of BHK cells that had received DNA of a clone containing HindIII-G, -H, -E, -I2, -O, -I1, and -P. The second type of antigen was found in the cytoplasm of cells cotransfected with clones containing Sal-A and HindIII-I2, -O, -I1, -P, and -C, whereas transfection of both individual clones failed to induce the antigen. Further analysis with subclones identified HindIII-G (5 kilobases) and HindIII-I2 (3 kilobases) plus the rightmost 3 kilobases of Sal-A as the sequences responsible for expression of the nuclear and the cytoplasmic antigen, respectively. The fact that two distant regions of the viral genome are required for expression of a viral antigen provides evidence for intergenomic regulation that can be studied in vitro.
将克隆的爱泼斯坦 - 巴尔病毒（EBV）DNA片段转染到幼仓鼠肾（BHK）细胞后，对EBV抗原的表达进行了研究。使用一组七个广泛重叠的克隆，这些克隆覆盖了无缺陷的爱泼斯坦 - 巴尔病毒株M - ABA的整个基因组，用于转染。将黏粒克隆转入BHK细胞导致两种不同抗原的表达，这通过使用人抗EBV血清的间接免疫荧光得以揭示。用针对EBV相关抗原具有不同反应性的人血清染色显示，这两种抗原均与早期抗原复合物相关。第一种抗原仅在接受了包含HindIII - G、- H、- E、- I2、- O、- I1和 - P的克隆DNA的BHK细胞核中检测到。第二种抗原在与包含Sal - A和HindIII - I2、- O、- I1、- P和 - C的克隆共转染的细胞的细胞质中发现，而单独转染这两个克隆均未能诱导该抗原。用亚克隆进行的进一步分析确定HindIII - G（5千碱基）和HindIII - I2（3千碱基）加上Sal - A最右侧的3千碱基分别为负责核抗原和细胞质抗原表达的序列。病毒基因组的两个远距离区域对于病毒抗原的表达是必需的，这一事实为可在体外研究的基因组间调控提供了证据。
