Papadopoulos Petros, Gutiérrez Laura, Demmers Jeroen, Scheer Elisabeth, Pourfarzad Farzin, Papageorgiou Dimitris N, Karkoulia Elena, Strouboulis John, van de Werken Harmen J G, van der Linden Reinier, Vandenberghe Peter, Dekkers Dick H W, Philipsen Sjaak, Grosveld Frank, Tora Làszlò
Department of Cell Biology, Erasmus MC, Rotterdam, The Netherlands Center for Human Genetics, KU Leuven, Leuven, Belgium
Department of Cell Biology, Erasmus MC, Rotterdam, The Netherlands Department of Blood Cell Research, Sanquin Research and Landsteiner Laboratory, AMC, Amsterdam, The Netherlands.
Mol Cell Biol. 2015 Jun;35(12):2103-18. doi: 10.1128/MCB.01370-14. Epub 2015 Apr 13.
The ordered assembly of a functional preinitiation complex (PIC), composed of general transcription factors (GTFs), is a prerequisite for the transcription of protein-coding genes by RNA polymerase II. TFIID, comprised of the TATA binding protein (TBP) and 13 TBP-associated factors (TAFs), is the GTF that is thought to recognize the promoter sequences allowing site-specific PIC assembly. Transcriptional cofactors, such as SAGA, are also necessary for tightly regulated transcription initiation. The contribution of the two TAF10-containing complexes (TFIID, SAGA) to erythropoiesis remains elusive. By ablating TAF10 specifically in erythroid cells in vivo, we observed a differentiation block accompanied by deregulated GATA1 target genes, including Gata1 itself, suggesting functional cross talk between GATA1 and TAF10. Additionally, we analyzed by mass spectrometry the composition of TFIID and SAGA complexes in mouse and human cells and found that their global integrity is maintained, with minor changes, during erythroid cell differentiation and development. In agreement with our functional data, we show that TAF10 interacts directly with GATA1 and that TAF10 is enriched on the GATA1 locus in human fetal erythroid cells. Thus, our findings demonstrate a cross talk between canonical TFIID and SAGA complexes and cell-specific transcription activators during development and differentiation.
由通用转录因子（GTF）组成的功能性起始前复合物（PIC）的有序组装是RNA聚合酶II转录蛋白质编码基因的前提条件。由TATA结合蛋白（TBP）和13种TBP相关因子（TAF）组成的TFIID是一种GTF，被认为可识别启动子序列，从而实现位点特异性PIC组装。转录辅因子，如SAGA，对于严格调控转录起始也很必要。两种含TAF10的复合物（TFIID、SAGA）对红细胞生成的作用仍不清楚。通过在体内特异性地剔除红细胞中的TAF10，我们观察到分化阻滞，并伴有GATA1靶基因（包括Gata1本身）的失调，这表明GATA1和TAF10之间存在功能相互作用。此外，我们通过质谱分析了小鼠和人类细胞中TFIID和SAGA复合物的组成，发现它们的整体完整性在红细胞分化和发育过程中得以维持，仅有微小变化。与我们的功能数据一致，我们表明TAF10直接与GATA1相互作用，并且TAF10在人类胎儿红细胞中的GATA1基因座上富集。因此，我们的研究结果证明了在发育和分化过程中，经典TFIID和SAGA复合物与细胞特异性转录激活因子之间存在相互作用。
