Physical and functional interactions between the transactivation domain of the hematopoietic transcription factor NF-E2 and WW domains.
Physical and functional interactions between the transactivation domain of the hematopoietic transcription factor NF-E2 and WW domains.
复制标题
造血转录因子 NF-E2 反式激活结构域和 WW 结构域之间的物理和功能相互作用。
DOI：
10.1021/bi981310l
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发表时间：
1998
期刊：
影响因子：
2.9
通讯作者：
Bresnick,EH
中科院分区：
文献类型：
--
作者：
Mosser,EA;Kasanov,JD;Forsberg,EC;Kay,BK;Ney,PA;Bresnick,EH
造血转录因子NF-E2在β-珠蛋白基因座控制区的串联结合位点激活转基因小鼠β-珠蛋白基因的高水平表达。NF-E2是一种异源二聚体，由造血亚基p45和普遍存在的亚基p18组成。Gavva et al. [N. R., Gavva， R., Ermekova， K., Sudol， M., and Shen， J. C.(1997)]。医学杂志。Chem. 272, 24105−24108]报道了人类p45含有一个结合WW结构域的PPXY基序。我们发现，小鼠NF-E2在其转激活域中含有两个PPXY基序（PPXY-1和-2），与9个GST - WW结构域融合蛋白发生差异相互作用。定量分析显示p45与造血组织中表达的一种新的人泛素连接酶同源物（WWP1）的WW结构域高亲和力结合（KD= 5.7 nM）。WWP1的氨基末端WW结构域与dna结合的NF-E2形成多聚体复合物。通过噬菌体展示分离的WWP1配体肽和跨越PPXY-1的肽抑制p45的结合，而SH3结构域相互作用肽和跨越PPXY-2的肽则没有抑制作用。PPXY-1的突变抑制了NF-E2的转激活功能，而PPXY-2的突变抑制了NF-E2的转激活功能，这为WW结构域相互作用对NF-E2介导的转激活很重要的假设提供了支持。
Tandem binding sites for the hematopoietic transcription factor NF-E2 in the β-globin locus control region activate high-level β-globin gene expression in transgenic mice. NF-E2 is a heterodimer consisting of a hematopoietic subunit p45 and a ubiquitous subunit p18. Gavva et al. [Gavva, N. R., Gavva, R., Ermekova, K., Sudol, M., and Shen, J. C. (1997)J. Biol. Chem. 272, 24105−24108] reported that human p45 contains a PPXY motif that binds WW domains. We show that murine NF-E2, which contains two PPXY motifs (PPXY-1 and -2) within its transactivation domain, differentially interacted with nine GST−WW domain fusion proteins. Quantitative analysis revealed high-affinity binding (KD= 5.7 nM) of p45 to a WW domain from a novel human ubiquitin ligase homologue (WWP1) expressed in hematopoietic tissues. The amino-terminal WW domain of WWP1 formed a multimeric complex with DNA-bound NF-E2. A WWP1 ligand peptide, isolated by phage display, and a peptide spanning PPXY-1 inhibited p45 binding, whereas an SH3 domain-interacting peptide and a peptide spanning PPXY-2 did not. Mutation of PPXY-1, but not PPXY-2, inhibited the transactivation function of NF-E2, providing support for the hypothesis that WW domain interactions are important for NF-E2-mediated transactivation.