Section of Molecular Biology, University of California at San Diego, La Jolla, California 92093, USA;
Stowers Institute for Medical Research, Kansas City, Missouri 64110, USA;
Genes Dev. 2014 Jul 15;28(14):1550-5. doi: 10.1101/gad.245662.114. Epub 2014 Jun 23.
The TCT core promoter element is present in most ribosomal protein (RP) genes in Drosophila and humans. Here we show that TBP (TATA box-binding protein)-related factor TRF2, but not TBP, is required for transcription of the TCT-dependent RP genes. In cells, TCT-dependent transcription, but not TATA-dependent transcription, increases or decreases upon overexpression or depletion of TRF2. In vitro, purified TRF2 activates TCT but not TATA promoters. ChIP-seq (chromatin immunoprecipitation [ChIP] combined with deep sequencing) experiments revealed the preferential localization of TRF2 at TCT versus TATA promoters. Hence, a specialized TRF2-based RNA polymerase II system functions in the synthesis of RPs and complements the RNA polymerase I and III systems.
TCT 核心启动子元件存在于果蝇和人类的大多数核糖体蛋白 (RP) 基因中。在这里,我们表明 TBP(TATA 盒结合蛋白)相关因子 TRF2 但不是 TBP,是 TCT 依赖性 RP 基因转录所必需的。在细胞中,TCT 依赖性转录,而不是 TATA 依赖性转录,在 TRF2 的过表达或耗竭时增加或减少。在体外,纯化的 TRF2 激活 TCT 但不激活 TATA 启动子。ChIP-seq(染色质免疫沉淀 [ChIP] 与深度测序相结合)实验表明,TRF2 优先定位于 TCT 而不是 TATA 启动子。因此,一种专门的基于 TRF2 的 RNA 聚合酶 II 系统在 RP 的合成中起作用,并补充了 RNA 聚合酶 I 和 III 系统。