Molecular analysis of the notch repressor-complex in Drosophila: characterization of potential hairless binding sites on suppressor of hairless.
Molecular analysis of the notch repressor-complex in Drosophila: characterization of potential hairless binding sites on suppressor of hairless.
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DOI：
10.1371/journal.pone.0027986
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发表时间：
2011
期刊：
影响因子：
3.7
通讯作者：
Maier D
中科院分区：
文献类型：
--
作者：
Kurth P;Preiss A;Kovall RA;Maier D
Notch信号通路在多种生物体中介导细胞间通讯。Notch信号转导的主要组成部分和基本机制在脊椎动物和无脊椎动物中都得到了很好的保护。Notch信号导致Notch靶基因的转录激活，这是由DNA结合蛋白CSL、Notch受体胞内结构域和转录辅激活因子Mastermind组成的激活因子复合物介导的。在缺乏主动信号传导的情况下，CSL通过募集辅抑制子来抑制Notch靶基因的转录。Notch激活物复合物是非常保守的，已经被详细研究过。然而，人们对Notch抑制因子复合物知之甚少。在黑腹果蝇中，CSL蛋白被称为无毛抑制因子[Su(H)]。Su(H)通过结合Drosophila Notch信号的主要拮抗剂Hairless作为转录抑制因子发挥作用，而Hairless又会招募两种通用的辅助抑制因子- Groucho和c -末端结合蛋白CtBP。最近，我们确定了Su(H)的c -末端结构域（CTD）与Hairless结合，并在Hairless中发现了一个与Su(H)接触所必需的位点。在这里，我们提出了额外的生化和体内研究，旨在绘制Su(H)中与Hairless接触的残基。聚焦于CTD表面暴露的残留物，我们在生化分析中确定了影响无毛结合的两个位点。这些位点的突变既不影响与DNA的结合，也不影响与Notch的结合。随后，这些Su(H)突变体在转基因果蝇的细胞和体内实验中被发现功能正常。然而，这些实验依赖于Su(H)过表达，不允许检测活性的定量或细微差异。我们讨论了我们的结果的含义。
The Notch signalling pathway mediates cell-cell communication in a wide variety of organisms. The major components, as well as the basic mechanisms of Notch signal transduction, are remarkably well conserved amongst vertebrates and invertebrates. Notch signalling results in transcriptional activation of Notch target genes, which is mediated by an activator complex composed of the DNA binding protein CSL, the intracellular domain of the Notch receptor, and the transcriptional coactivator Mastermind. In the absence of active signalling, CSL represses transcription from Notch target genes by the recruitment of corepressors. The Notch activator complex is extremely well conserved and has been studied in great detail. However, Notch repressor complexes are far less understood. In Drosophila melanogaster, the CSL protein is termed Suppressor of Hairless [Su(H)]. Su(H) functions as a transcriptional repressor by binding Hairless, the major antagonist of Notch signalling in Drosophila, which in turn recruits two general corepressors – Groucho and C-terminal binding protein CtBP. Recently, we determined that the C-terminal domain (CTD) of Su(H) binds Hairless and identified a single site in Hairless, which is essential for contacting Su(H). Here we present additional biochemical and in vivo studies aimed at mapping the residues in Su(H) that contact Hairless. Focusing on surface exposed residues in the CTD, we identified two sites that affect Hairless binding in biochemical assays. Mutation of these sites neither affects binding to DNA nor to Notch. Subsequently, these Su(H) mutants were found to function normally in cellular and in vivo assays using transgenic flies. However, these experiments rely on Su(H) overexpression, which does not allow for detection of quantitative or subtle differences in activity. We discuss the implications of our results.
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影响因子：
64.5
作者：
GYURIS, J;GOLEMIS, E;BRENT, R
通讯作者：
BRENT, R
影响因子：
10.5
作者：
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作者：
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DOI：
10.1073/pnas.242596699
发表时间：
2002-11-26
影响因子：
11.1
作者：
Maier, D;Nagel, AC;Preiss, A
通讯作者：
Preiss, A
DOI：
10.1073/pnas.94.10.5195
发表时间：
1997-05-13
影响因子：
11.1
作者：
Hay, BA;Maile, R;Rubin, GM
通讯作者：
Rubin, GM