Raman B, Guarnaccia C, Nadassy K, Zakhariev S, Pintar A, Zanuttin F, Frigyes D, Acatrinei C, Vindigni A, Pongor G, Pongor S
International Centre for Genetic Engineering and Biotechnology, Padriciano 99, 34012 Trieste, Italy.
Nucleic Acids Res. 2001 Aug 15;29(16):3377-84. doi: 10.1093/nar/29.16.3377.
We studied the interaction between a synthetic peptide (sequence Ac-GXGGFGGXGGFXGGXGG-NH(2), where X = arginine, N(omega),N(omega)-dimethylarginine, DMA, or lysine) corresponding to residues 676-692 of human nucleolin and several DNA and RNA substrates using double filter binding, melting curve analysis and circular dichroism spectroscopy. We found that despite the reduced capability of DMA in forming hydrogen bonds, N(omega),N(omega)-dimethylation does not affect the strength of the binding to nucleic acids nor does it have any effect on stabilization of a double-stranded DNA substrate. However, circular dichroism studies show that unmethylated peptide can perturb the helical structure, especially in RNA, to a much larger extent than the DMA peptide.
我们使用双滤膜结合、熔解曲线分析和圆二色光谱法，研究了一种对应于人核仁素676 - 692位残基的合成肽（序列为Ac - GXGGFGGXGGFXGGXGG - NH₂，其中X = 精氨酸、N(ω),N(ω)-二甲基精氨酸、DMA或赖氨酸）与几种DNA和RNA底物之间的相互作用。我们发现，尽管DMA形成氢键的能力降低，但N(ω),N(ω)-二甲基化并不影响与核酸结合的强度，对双链DNA底物的稳定性也没有任何影响。然而，圆二色性研究表明，未甲基化的肽比DMA肽能更大程度地扰乱螺旋结构，尤其是在RNA中。
