Department of Physics, Northeastern University, Boston, MA, USA.
RNA Biol. 2010 Nov-Dec;7(6):712-23. doi: 10.4161/rna.7.6.13776. Epub 2010 Nov 1.
RNA chaperone proteins play significant roles in diverse biological contexts. The most widely studied RNA chaperones are the retroviral nucleocapsid proteins (NC), also referred to as nucleic acid (NA) chaperones. Surprisingly, the biophysical properties of the NC proteins vary significantly for different viruses, and it appears that HIV-1 NC has optimal NA chaperone activity. In this review we discuss the physical nature of the NA chaperone activity of NC. We conclude that the optimal NA chaperone must saturate NA binding, leading to strong NA aggregation and slight destabilization of all NA duplexes. Finally, rapid kinetics of the chaperone protein interaction with NA is another primary component of its NA chaperone activity. We discuss these characteristics of HIV-1 NC and compare them with those of other NA binding proteins and ligands that exhibit only some characteristics of NA chaperone activity, as studied by single molecule DNA stretching.
RNA 伴侣蛋白在多种生物背景下发挥着重要作用。研究最为广泛的 RNA 伴侣蛋白是逆转录病毒核衣壳蛋白(NC),也称为核酸(NA)伴侣蛋白。令人惊讶的是,不同病毒的 NC 蛋白的生物物理特性差异很大,似乎 HIV-1 NC 具有最佳的 NA 伴侣活性。在这篇综述中,我们讨论了 NC 的 NA 伴侣活性的物理性质。我们得出结论,最佳的 NA 伴侣必须饱和 NA 结合,导致强烈的 NA 聚集和所有 NA 双链体的轻微去稳定化。最后,与 NA 的伴侣蛋白相互作用的快速动力学是其 NA 伴侣活性的另一个主要组成部分。我们讨论了 HIV-1 NC 的这些特性,并将其与其他仅表现出 NA 伴侣活性某些特征的 NA 结合蛋白和配体进行了比较,这些特性是通过单分子 DNA 拉伸研究的。