Structural and functional characterization of an atypical activation domain in erythroid Kruppel-like factor (EKLF)
Structural and functional characterization of an atypical activation domain in erythroid Kruppel-like factor (EKLF)
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DOI：
10.1073/pnas.1017029108
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发表时间：
2011-06-28
影响因子：
11.1
通讯作者：
Omichinski, James G.
中科院分区：
文献类型：
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作者：
Mas, Caroline;Lussier-Price, Mathieu;Omichinski, James G.
红系Kruppel样因子（EKLF）通过刺激β-珠蛋白基因表达在红系发育中起重要作用。我们已经研究了EKLF的最小反式激活结构域（EKLF）与几种转录调控因子相互作用的细节。我们报告说，EKLFTAD显示同源性的p53蛋白，并像p53蛋白，可以分为两个功能亚结构域（EKLFTAD 1和EKLFTAD 2）。基于序列分析，我们发现EKLFTAD 2在KLF 2、KLF 4、KLF 5和KLF 15中是保守的。此外，我们证明EKLFTAD 2结合TFIIH的Tfb 1/p62亚基的氨基末端PH结构域（Tfb 1 PH/p62 PH）和CREB结合蛋白/p300的四个结构域。EKLFTAD 2/Tfb 1 PH复合物的溶液结构表明EKLFTAD 2以延伸构象结合Tfb 1 PH，这与p53 TAD 2与Tfb 1 PH复合物中所见的α-螺旋构象相反。这些研究提供了详细的机制信息EKLF功能，以及其他KLF蛋白的TADs的潜在相互作用的见解。此外，他们认为，酸性TADs不仅进化成使用不同的构象结合在共同的靶标上，而且从无序状态转变为更有序的状态并不是它们结合多个伴侣的能力的必要条件。
Erythroid Kruppel-like factor (EKLF) plays an important role in erythroid development by stimulating beta-globin gene expression. We have examined the details by which the minimal transactivation domain (TAD) of EKLF (EKLFTAD) interacts with several transcriptional regulatory factors. We report that EKLFTAD displays homology to the p53TAD and, like the p53TAD, can be divided into two functional subdomains (EKLFTAD1 and EKLFTAD2). Based on sequence analysis, we found that EKLFTAD2 is conserved in KLF2, KLF4, KLF5, and KLF15. In addition, we demonstrate that EKLFTAD2 binds the amino-terminal PH domain of the Tfb1/p62 subunit of TFIIH (Tfb1PH/p62PH) and four domains of CREB-binding protein/p300. The solution structure of the EKLFTAD2/Tfb1PH complex indicates that EKLFTAD2 binds Tfb1PH in an extended conformation, which is in contrast to the alpha-helical conformation seen for p53TAD2 in complex with Tfb1PH. These studies provide detailed mechanistic information into EKLFTAD functions as well as insights into potential interactions of the TADs of other KLF proteins. In addition, they suggest that not only have acidic TADs evolved so that they bind using different conformations on a common target, but that transitioning from a disordered to a more ordered state is not a requirement for their ability to bind multiple partners.