Adam E, Kerkhofs P, Mammerickx M, Kettmann R, Burny A, Droogmans L, Willems L
Department of Molecular Biology, University of Brussels, Rhode-St-Genèse, Belgium.
J Virol. 1994 Sep;68(9):5845-53. doi: 10.1128/JVI.68.9.5845-5853.1994.
The TAR element (Tax-responsive element; also called TxRE) is a major determinant of the regulation of bovine leukemia virus (BLV) expression. In order to gain insight into the mechanisms of viral expression, complexes formed between proteins and the TAR enhancer DNA were analyzed by gel retardation assays. We report here that nuclear lysates from ex vivo-isolated B lymphocytes contain proteins that specifically bind to TAR. An antibody directed toward the cyclic AMP-responsive element binding (CREB) protein supershifted a complex (C1) present only in BLV-infected B lymphocytes. The CREB protein thus appears to be a major transcription factor involved in BLV expression in vivo.
TAR元件（Tax反应元件；也称为TxRE）是牛白血病病毒（BLV）表达调控的主要决定因素。为了深入了解病毒表达机制，通过凝胶阻滞试验分析了蛋白质与TAR增强子DNA形成的复合物。我们在此报告，体外分离的B淋巴细胞的核裂解物中含有能特异性结合TAR的蛋白质。一种针对环磷酸腺苷反应元件结合（CREB）蛋白的抗体使仅存在于BLV感染的B淋巴细胞中的一种复合物（C1）发生超迁移。因此，CREB蛋白似乎是体内参与BLV表达的主要转录因子。
