Spontaneous membrane-translocating peptides: influence of peptide self-aggregation and cargo polarity
Spontaneous membrane-translocating peptides: influence of peptide self-aggregation and cargo polarity
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DOI：
10.1038/srep16914
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发表时间：
2015-11-16
影响因子：
4.6
通讯作者：
Cardarelli, Francesco
中科院分区：
文献类型：
--
作者：
Macchi, Sara;Signore, Giovanni;Cardarelli, Francesco
自发地跨细胞膜转运的多肽可以通过使细胞膜不允许的分子转运到细胞中来改变药物输送领域。在这方面，最近通过高通量筛选发现了一个携带极性染料自发跨膜易位的9个氨基酸长的基序（代表性序列：PLIYLRLLR，以下简称易位基序9，TM9）。在这里，我们通过试管内理化分析、合理诱变、活细胞共聚焦成像和荧光相关光谱测量相结合来研究其传输特性。我们揭示了TM9以浓度依赖的方式自聚集的能力，并证明肽自聚集是有效膜易位的必要但不充分的步骤。此外，我们表明，膜交叉可以发生与极性载荷，而它是完全抑制极性载荷。对这些发现进行了讨论，并与以前的报告进行了比较。目前的结果强加了一个仔细的重新思考这类序列的直接易位载体适合交付的目的。
Peptides that translocate spontaneously across cell membranes could transform the field of drug delivery by enabling the transport of otherwise membrane-impermeant molecules into cells. In this regard, a 9-aminoacid-long motif (representative sequence: PLIYLRLLR, hereafter Translocating Motif 9, TM9) that spontaneously translocates across membranes while carrying a polar dye was recently identified by high-throughput screening. Here we investigate its transport properties by a combination of in cuvette physico-chemical assays, rational mutagenesis, live-cell confocal imaging and fluorescence correlation spectroscopy measurements. We unveil TM9 ability to self-aggregate in a concentration-dependent manner and demonstrate that peptide self-aggregation is a necessary yet not sufficient-step for effective membrane translocation. Furthermore we show that membrane crossing can occur with apolar payloads while it is completely inhibited by polar ones. These findings are discussed and compared to previous reports. The present results impose a careful rethinking of this class of sequences as direct-translocation vectors suitable for delivery purposes.