Uniform transitions of the general RNA polymerase II transcription complex
Uniform transitions of the general RNA polymerase II transcription complex
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DOI：
10.1038/nsmb.1903
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发表时间：
2010-10-01
影响因子：
16.8
通讯作者：
Cramer, Patrick
中科院分区：
文献类型：
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作者：
Mayer, Andreas;Lidschreiber, Michael;Cramer, Patrick
我们展示了增殖酵母中 RNA 聚合酶 (Pol) II、其磷酸化形式和转录因子的全基因组占用谱。 Pol II 在 5' 转换期间将起始因子交换为延伸因子，该转换在转录起始位点 (TSS) 下游 150 个核苷酸处完成。所得的延伸复合物由所有延伸因子组成，并且在 Pol II 的 C 端重复结构域 (CTD) 上显示出高水平的 Ser7 和 Ser5 磷酸化。 Ser2 磷酸化水平增加直至 TSS 下游 600-1,000 个核苷酸，并且与 Spt6 和 Pcf11 的募集无关，Spt6 和 Pcf11 在体外与 Ser2 磷酸化 CTD 结合。这表明 CTD 独立的招募机制和体内 CTD 掩蔽。延伸复合物在两步 3' 转变中具有生产力和分解性。 Paf1、Spt16（FACT 复合体的一部分）和 CTD 激酶 Bur1 和 Ctk1 从多腺苷酸化位点上游退出，而 Spt4、Spt5、Spt6、Spn1（也称为 Iws1）和 Elf1 从下游退出。转变是一致的并且独立于基因长度、类型和表达。
We present genome-wide occupancy profiles for RNA polymerase (Pol) II, its phosphorylated forms and transcription factors in proliferating yeast. Pol II exchanges initiation factors for elongation factors during a 5' transition that is completed 150 nucleotides downstream of the transcription start site (TSS). The resulting elongation complex is composed of all the elongation factors and shows high levels of Ser7 and Ser5 phosphorylation on the C-terminal repeat domain (CTD) of Pol II. Ser2 phosphorylation levels increase until 600-1,000 nucleotides downstream of the TSS and do not correlate with recruitment of Spt6 and Pcf11, which bind the Ser2-phosphorylated CTD in vitro. This indicates CTD-independent recruitment mechanisms and CTD masking in vivo. Elongation complexes are productive and disassemble in a two-step 3' transition. Paf1, Spt16 (part of the FACT complex), and the CTD kinases Bur1 and Ctk1 exit upstream of the polyadenylation site, whereas Spt4, Spt5, Spt6, Spn1 (also called Iws1) and Elf1 exit downstream. Transitions are uniform and independent of gene length, type and expression.