Deshayes Sébastien, Konate Karidia, Aldrian Gudrun, Heitz Frédéric, Divita Gilles
Department of Molecular Biophysics and Therapeutics, Centre de Recherches de Biochimie Macromoléculaire, Montpellier, France.
Methods Mol Biol. 2011;683:41-56. doi: 10.1007/978-1-60761-919-2_4.
Due to the poor permeability of the plasma membrane, several strategies are designed to enhance the transfer of therapeutics into cells. Over the last 20 years, small peptides called Cell-Penetrating Peptides (CPPs) have been widely developed to improve the cellular delivery of biomolecules. These small peptides derive from protein transduction domains, chimerical constructs, or model sequences. Several CPPs are primary or secondary amphipathic peptides, depending on whether the distribution of their hydrophobic and hydrophilic domains occurs from their amino-acid sequence or through α-helical folding. Most of the CPPs are able to deliver different therapeutics such as nucleic acids or proteins in vitro and in vivo. Although their mechanisms of internalization are varied and controversial, the understanding of the intrinsic features of CPPs is essential for future developments. This chapter describes several protocols for the investigation of biophysical properties of amphipathic CPPs. Surface physics approaches are specifically applied to characterize the interactions of amphipathic peptides with model membranes. Circular dichroism and infra-red spectroscopy allow the identification of their structural state. These methods are exemplified by the analyses of the main biophysical features of the cell-penetrating peptides MPG, Pep-1, and CADY.
由于质膜的通透性较差，人们设计了多种策略来增强治疗药物进入细胞的转运。在过去20年中，一种名为细胞穿透肽（CPPs）的小肽被广泛开发，以改善生物分子的细胞递送。这些小肽来源于蛋白质转导结构域、嵌合构建体或模型序列。根据其疏水和亲水结构域的分布是源于其氨基酸序列还是通过α-螺旋折叠，几种CPPs属于一级或二级两亲性肽。大多数CPPs能够在体外和体内递送不同的治疗药物，如核酸或蛋白质。尽管它们的内化机制各不相同且存在争议，但了解CPPs的内在特性对于未来的发展至关重要。本章介绍了几种研究两亲性CPPs生物物理性质的方案。表面物理方法专门用于表征两亲性肽与模型膜的相互作用。圆二色性和红外光谱可用于鉴定它们的结构状态。这些方法通过对细胞穿透肽MPG、Pep-1和CADY的主要生物物理特征的分析进行举例说明。
