Effect of the nuclear factors EmBP1 and viviparous1 on the transcription of the Em gene in HeLa nuclear extracts.
Effect of the nuclear factors EmBP1 and viviparous1 on the transcription of the Em gene in HeLa nuclear extracts.
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DOI：
10.1105/tpc.9.10.1791
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发表时间：
1997-10
期刊：
影响因子：
--
通讯作者：
M. A. Razik;R. Quatrano
中科院分区：
文献类型：
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作者：
M. A. Razik;R. Quatrano
从小麦Em和玉米rab28启动子构建的模板在由HeLa细胞核制备的良好表征的无细胞转录系统中有效且准确地转录。Em启动子的缺失分析表明，转录需要一个G盒（CACGTG）元件（Em1b）。USF是HeLa细胞核提取物中的Myc转录因子，通过与Em1b结合来激活转录，如针对USF产生的抗体在电泳迁移率变动测定中抑制转录和干扰Em1b复合物形成的能力所示。此外，从玉米到HeLa细胞核提取物的重组Viviparous1蛋白特异性刺激的Em启动子的转录，但依赖于提取物中USF的存在。在USF耗尽的提取物中，添加重组EmBP 1，一种来自小麦的碱性亮氨酸拉链转录因子，通过Em1b以及腺病毒主要晚期启动子中类似的G盒激活转录。我们的研究表明，HeLa细胞核提取物中的基本转录装置支持植物启动子的转录，并可用于测定某些植物核蛋白的功能，从而有助于确定它们对转录的影响。
Templates constructed from the wheat Em and maize rab28 promoters are efficiently and accurately transcribed in the well-characterized cell-free transcription system prepared from HeLa nuclei. Deletion analysis of the Em promoter indicates that a G-box (CACGTG) element (Em1b) is required for transcription. USF, a Myc transcription factor in HeLa nuclear extracts, activates transcription by binding to Em1b, as shown by the ability of an antibody raised against USF to inhibit transcription and to interfere with Em1b complex formation in an electrophoretic mobility shift assay. The addition of the recombinant Viviparous1 protein from maize to HeLa nuclear extracts specifically stimulated transcription of the Em promoter but was dependent on the presence of USF in the extract. In USF-depleted extracts, the addition of recombinant EmBP1, a basic leucine zipper transcription factor from wheat, activated transcription through Em1b as well as from a similar G-box in the adenovirus major late promoter. Our study demonstrates that the basic transcriptional apparatus in HeLa nuclear extract supports transcription from plant promoters and can be used to assay the function of certain plant nuclear proteins, thereby helping to determine their effects on transcription.