A Non-Invasive NMR Method Based on Histidine Imidazoles to Analyze the pH-Modulation of Protein-Nucleic Acid Interfaces
A Non-Invasive NMR Method Based on Histidine Imidazoles to Analyze the pH-Modulation of Protein-Nucleic Acid Interfaces
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DOI：
10.1002/chem.201405538
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发表时间：
2015-05-11
影响因子：
4.3
通讯作者：
Diaz-Moreno, Irene
中科院分区：
文献类型：
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作者：
Cruz-Gallardo, Isabel;Del Conte, Rebecca;Diaz-Moreno, Irene
提出了一种有用的(2)J（N-H）偶联核磁共振光谱方法，在分子水平上揭示来自RNA/DNA结合蛋白的组氨酸的咪唑基团对ph对核酸结合的调节的贡献。这种质子化/去质子化事件已在位于t细胞内抗原-1 （TIA-1）蛋白的第二个RNA/DNA识别基序（RRM2）的单个His96上进行了监测。与分离的TIA-1 RRM2相比，在短u -富RNA和t -富DNA寡核苷酸复合物中，His96可电离基团的pK(a)值明显更高。本文采用了测定组氨酸侧链在DNA/RNA结合时pK(a)变化的方法，为了解pH对在不同细胞间穿梭的多结构域DNA/RNA结合蛋白的影响提供了有价值的信息。
A useful (2)J(N-H) coupling-based NMR spectroscopic approach is proposed to unveil, at the molecular level, the contribution of the imidazole groups of histidines from RNA/DNA-binding proteins on the modulation of binding to nucleic acids by pH. Such protonation/deprotonation events have been monitored on the single His96 located at the second RNA/DNA recognition motif (RRM2) of T-cell intracellular antigen-1 (TIA-1) protein. The pK(a) values of the His96 ionizable groups were substantially higher in the complexes with short U-rich RNA and T-rich DNA oligonucleotides than those of the isolated TIA-1 RRM2. Herein, the methodology applied to determine changes in pK(a) of histidine side chains upon DNA/RNA binding, gives valuable information to understand the pH effect on multidomain DNA/RNA-binding proteins that shuttle among different cellular compartments.