Evidence for a functionally relevant rocaglamide binding site on the eIF4A-RNA complex.
Evidence for a functionally relevant rocaglamide binding site on the eIF4A-RNA complex.
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DOI：
10.1021/cb400158t
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发表时间：
2013-07-19
影响因子：
4
通讯作者：
Movva, N. Rao
中科院分区：
文献类型：
--
作者：
Sadlish, Heather;Galicia-Vazquez, Gabriela;Paris, C. Gregory;Aust, Thomas;Bhullar, Bhupinder;Chang, Lena;Helliwell, Stephen B.;Hoepfner, Dominic;Knapp, Britta;Riedl, Ralph;Roggo, Silvio;Schuierer, Sven;Studer, Christian;Porco, John A., Jr.;Pelletier, Jerry;Movva, N. Rao
翻译起始是肿瘤学和神经生物学适应症中的新兴靶点。天然衍生的和合成的罗格列胺支架已被用于研究这一途径，然而，关于其确切的作用机制还不确定。我们利用酵母的遗传易处理性来定义天然和合成罗格列胺在细胞环境中的主要作用，并使用生物化学研究和计算机模拟来表征分子靶标。酵母中的化学基因组分析和诱变鉴定了eIF（真核起始因子）4A解旋酶同源物作为罗格列酰胺的主要分子靶标，并在RNA结合基序附近定义了一组离散的残基，这些残基赋予对两种化合物的抗性。三个eIF 4A突变的特征在于其对活性和对罗格列胺抑制反应的功能后果。这些数据支持罗格列酰胺稳定eIF 4A-RNA相互作用以改变eIF 4F复合物的水平和/或损害其活性的模型。此外，计算机模拟支持由RNA底物和从我们的诱变筛选中鉴定的残基描绘的结合口袋的注释。正如真核生物翻译途径高度保守所预期的那样，这些观察结果与哺乳动物模型系统中的先前观察结果一致。重要的是，我们证明化学上不同的西维司群和合成的罗卡酰胺具有共同的作用机制，这对于优化生理稳定的衍生物至关重要。最后，这些数据证实了罗格列胺支架在探索翻译调节对疾病的影响方面的价值。
Translation initiation is an emerging target in oncology and neurobiology indications. Naturally derived and synthetic rocaglamide scaffolds have been used to interrogate this pathway, however, there is uncertainty regarding their precise mechanism(s) of action. We exploited the genetic tractability of yeast to define the primary effect of both a natural and a synthetic rocaglamide in a cellular context, and characterized the molecular target using biochemical studies and in silico modeling. Chemogenomic profiling and mutagenesis in yeast identified the eIF (eukaryotic Initiation Factor) 4A helicase homologue as the primary molecular target of rocaglamides, and defined a discrete set of residues near the RNA binding motif which confer resistance to both compounds. Three of the eIF4A mutations were characterized regarding their functional consequences on activity and response to rocaglamide inhibition. These data support a model whereby rocaglamides stabilize an eIF4A-RNA interaction to either alter the level and/or impair the activity of the eIF4F complex. Furthermore, in silico modeling supports the annotation of a binding pocket delineated by the RNA substrate and the residues identified from our mutagenesis screen. As expected from the high degree of conservation of the eukaryotic translation pathway, these observations are consistent with previous observations in mammalian model systems. Importantly, we demonstrate that the chemically distinct silvestrol and synthetic rocaglamides share a common mechanism of action, which will be critical for optimization of physiologically stable derivatives. Finally, these data confirm the value of the rocaglamide scaffold for exploring the impact of translational modulation on disease.
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影响因子：
5.6
作者：
Halgren, Thomas A.
通讯作者：
Halgren, Thomas A.
影响因子：
3.6
作者：
Hwang, BY;Su, BN;Kinghorn, AD
通讯作者：
Kinghorn, AD
影响因子：
5.2
作者：
Chambers, Jennifer M.;Lindqvist, Lisa M.;Rizzacasa, Mark A.
通讯作者：
Rizzacasa, Mark A.
DOI：
10.1006/meth.1996.0431
发表时间：
1997-04-01
期刊：
METHODS-A COMPANION TO METHODS IN ENZYMOLOGY
影响因子：
--
作者：
Merrick, WC;Sonenberg, N
通讯作者：
Sonenberg, N
影响因子：
--
作者：
Grech G;von Lindern M
通讯作者：
von Lindern M