Kalinski H, Mashiah P, Rotem D, Orzech Y, Sherman L, Miki T, Yaniv A, Gazit A, Tronick S R
Department of Human Microbiology, Sackler School of Medicine, Tel Aviv University, Israel.
Virology. 1994 Nov 1;204(2):828-34. doi: 10.1006/viro.1994.1602.
Two distinct species of caprine arthritis encephalitis virus (CAEV) tat cDNAs were isolated early after infection of a Himalayan tahr cell line. Sequence analyses predicted that one cDNA (pCEV/e1) represented a polycistronic transcript that encodes Tat and Rev as well as an N-terminally truncated transmembrane protein and a protein, designated X, whose function is unknown; whereas the other cDNA (pCEV/f1) encodes Tat and the env gene products. pCEV/e1 trans-activated a CAEV LTR-chloramphenicol acetyltransferase reporter gene in goat synovial membrane cells. This activity was shown to be encoded by the Tat open reading frame by analysis of a deletion mutant. Because the pCAEV/f1 insert was unstable in plasmid form, its Tat activity could not be convincingly demonstrated. The target sequences for Tat within the CAEV LTR were localized to the U3 region which, when placed in either orientation upstream of heterologous promoters, was able to confer responsiveness to Tat.
在感染喜马拉雅塔尔羊细胞系后不久，分离出了两种不同的山羊关节炎脑炎病毒（CAEV）tat cDNA。序列分析预测，一种cDNA（pCEV/e1）代表一种多顺反子转录本，其编码Tat和Rev以及一个N端截短的跨膜蛋白和一种名为X的功能未知的蛋白；而另一种cDNA（pCEV/f1）编码Tat和env基因产物。pCEV/e1在山羊滑膜细胞中反式激活了CAEV LTR - 氯霉素乙酰转移酶报告基因。通过对缺失突变体的分析表明，这种活性由Tat开放阅读框编码。由于pCAEV/f1插入片段以质粒形式不稳定，其Tat活性无法令人信服地得到证实。CAEV LTR内Tat的靶序列定位于U3区域，当该区域置于异源启动子上游的任何方向时，都能够赋予对Tat的反应性。
