The homologous pairing domain of RecA also mediates the allosteric regulation of DNA binding and ATP hydrolysis: a remarkable concentration of functional residues.
The homologous pairing domain of RecA also mediates the allosteric regulation of DNA binding and ATP hydrolysis: a remarkable concentration of functional residues.
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RecA 的同源配对结构域还介导 DNA 结合和 ATP 水解的变构调节：功能残基的显着浓度。
DOI：
10.1006/jmbi.2000.4163
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发表时间：
2000
影响因子：
5.6
通讯作者：
Camerini-Otero,RD
中科院分区：
文献类型：
--
作者：
Voloshin,ON;Wang,L;Camerini-Otero,RD
同源重组RecA蛋白的活性构象(ATP和DNA结合)和非活性构象之间的转换受ATP水解酶的调节。首先，我们利用来自其移动环L2的RecA的同源配对结构域来证明这种随机卷曲多肽与三磷酸腺苷的γ-磷酸相互作用产生一种类似于先前被证明由β结合诱导的多肽构象。接下来，我们证明了在整个RecA蛋白中，该L2结构域的两个残基Gln194和Arg196是ATP水解的催化氨基酸残基，在功能上类似于两类不同的G蛋白参与GTP水解的相应残基。最后，我们证明了DNA和高盐在刺激RecA的ATPase中的作用是稳定这个参与水解的高流动性区域。这与RGSS在激活异源三聚体G蛋白的GTP酶中所描述的作用类似。因此，(I)典型的依赖DNA的ATPase和ATP刺激的DNA结合蛋白RecA和真核信号蛋白具有共同的立体化学调控机制；以及(Ii)在简约的一个显著例子中，环L2是一个分子开关，控制着ATP促进的DNA结合和配对反应以及DNA刺激的ATP水解。
Switching between the active (ATP and DNA bound) and inactive conformations of the homologous recombination RecA protein is regulated by ATP hydrolysis. First, we use the homologous pairing domain of RecA derived from its mobile loop L2 to show that the interaction of this random coil peptide with the γ-phosphate of ATP results in a peptide β-conformation similar to that previously shown to be induced by DNA binding. Next, we show that in the whole RecA protein two residues in this L2 domain, Gln194 and Arg196, are catalytic amino acid residues for ATP hydrolysis and functionally resemble the corresponding residues engaged in GTP hydrolysis by two distinct classes of G proteins. Finally, we show that the role of DNA and high salt in the stimulation of the ATPase of RecA is to stabilize this highly mobile region involved in hydrolysis. This is a role similar to that described for RGSs in the activation of the GTPase of heterotrimeric G proteins. Therefore, (i) a prototypical DNA-dependent ATPase and ATP-stimulated DNA-binding protein, RecA, and eukaryotic signaling proteins share common stereochemical regulatory mechanisms; and (ii) in a remarkable example of parsimony, loop L2 is a molecular switch that controls both ATP promoted DNA binding and pairing reactions and DNA stimulated ATP hydrolysis.