Punyammalee B, Crabeel M, de Lannoy C, Perbal B, Glansdorff N
Microbiology, Vrije Universiteit Brussel, c/o Research Institute of the CERIA-COOVI, Belgium.
Oncogene. 1991 Jan;6(1):11-9.
We assayed in the yeast S. cerevisiae the transcriptional transactivation activity of the c-myb products encoded by a normal thymus cDNA and of an aminoterminally truncated version of it (minus 58 amino acids) corresponding to the cDNAs isolated from lymphoma and leukemia cells from different origins. Both proto-oncogene products were expressed under the control of the galactose inducible GAL10 promoter. The reporter system used to monitor the transactivation potential of the myb products consisted of a CYCl-lacZ gene fusion in which the UASCYC signals were replaced by one or multiple copies of the myb recognition element (mRE). As shown by Northern blot analyses and by primer extension experiments both c-myb products increase the level of beta-galactosidase transcription. Interestingly, the c-myb product corresponding to lymphoma cDNAs stimulates transcription four to five times more efficiently than does the normal thymic c-myb product.
我们在酿酒酵母中检测了由正常胸腺cDNA编码的c-myb产物以及其氨基末端截短形式（缺失58个氨基酸）的转录反式激活活性，该截短形式对应于从不同来源的淋巴瘤和白血病细胞中分离出的cDNA。两种原癌基因产物均在半乳糖诱导型GAL10启动子的控制下表达。用于监测myb产物反式激活潜能的报告系统由一个CYC1-lacZ基因融合体组成，其中CYC的上游激活序列（UASCYC）信号被一个或多个myb识别元件（mRE）拷贝所取代。如Northern印迹分析和引物延伸实验所示，两种c-myb产物均能提高β-半乳糖苷酶的转录水平。有趣的是，对应于淋巴瘤cDNA的c-myb产物刺激转录的效率比正常胸腺c-myb产物高4至5倍。
