Research And Comparison On Mechanism Of Novel Cell-Penetrating Peptides

Cell-penetrating peptides (CPPs), are usually composed of basic amino acids. They can be used as the carriers to carry substances into the cell, but the mechanism are still in great controversy. After construction, expression and purification of different cell-penetrating peptides with fluorescence protein, detect the transmembrane mechanism and penetrating efficiency using fluorescence microscopy, laser scanning confocal and flow cytometry.In this experiment, EGFP-CS, EGFP-CS4, EGFP-TAT, TAT-mCherry, Nus-S Tag-EGFP-CS and EGFP-CPPs, are constructed by molecular biology technology and purified by Ni-NTA column chromatography with purity above 95%.Study of fusion protein EGFP-TAT, EGFP-CS and EGFP-CS4 in different concentration and different time into the cell, shows their dependence on time and concentration.Through the endocytic pathway inhibitors, cell-penetrating peptides CS and CS4 mainly depend on the cell membrane and the sulfate proteoglycan, in addition a small amount can also enter the cell through other means by mixed approach.Cell-penetrating peptide CS with high molecular weight protein Nus-S Tag-EGFP, although at the same concentration, the fluorescence activity relative to EGFP-CS is weak, but with the increase of concentration, the fluorescent activity gradually increase can be detected in cells, which indicates that the molecule has a certain effect on the transmembrane peptide transmembrane action.Study on different transmembrane peptides in a variety of cells found, cell-penetrating peptides CS and CS4 has a broad spectrum of relative, but for the two kinds of cells with the MKN and A549.Comparison of various human transmembrane peptide transmembrane efficiency shows a variety of human transmembrane activity peptide has higher transmembrane efficiency, and can be applied to clinical medicine.