title: Gene transport and expression by arginine-rich cell-penetrating peptides in Paramecium.
abstract: Owing to the cell membrane barriers, most macromolecules and hydrophilic molecules could not freely enter into living cells. However, cell-penetrating peptides (CPPs) have been discovered that can translocate themselves and associate cargoes into the cytoplasm. In this study, we demonstrate that three arginine-rich CPPs (SR9, HR9 and PR9) can form stable complexes with plasmid DNA at the optimized nitrogen/phosphate ratio of 3 and deliver plasmid DNA into Paramecium caudatum in a noncovalent manner. Accordingly, the transported plasmid encoding the green fluorescent protein (GFP) gene could be expressed in cells functionally assayed at both the protein and DNA levels. The efficiency of gene delivery varied among these CPPs in the order of HR9>PR9>SR9. In addition, these CPPs and CPP/DNA complexes were not cytotoxic in Paramecium detected by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diohenyltetrazolium bromide (MTT) assay. Thus, these results suggest that the functionality of arginine-rich CPPs offers an efficient and safe tool for transgenesis in eukaryotic protozoans.
authors.affiliation: Department of Natural Resources and Environmental Studies, National Dong Hwa University, Hualien, Taiwan.
authors.forename: Yun-Hao
authors.initials: YH
authors.lastname: Dai
authors.forename: Betty Revon
authors.initials: BR
authors.lastname: Liu
authors.forename: Huey-Jenn
authors.initials: HJ
authors.lastname: Chiang
authors.forename: Han-Jung
authors.initials: HJ
authors.lastname: Lee
mesh_terms: D001120:Arginine / Q000737:chemistry; D001692:Biological Transport; D002352:Carrier Proteins / Q000378:metabolism; D002462:Cell Membrane / Q000378:metabolism; D002468:Cell Physiological Phenomena; D057846:Cell-Penetrating Peptides / Q000378:metabolism*; D016054:DNA, Protozoan / Q000378:metabolism; D017125:Genes, Protozoan; D049452:Green Fluorescent Proteins; D008856:Microscopy, Fluorescence; D048488:Paramecium caudatum / Q000235:genetics* / Q000378:metabolism*; D010957:Plasmids; D013778:Tetrazolium Salts; D013844:Thiazoles; D014162:Transfection
chemical_list: D002352:Carrier Proteins; D057846:Cell-Penetrating Peptides; D016054:DNA, Protozoan; D013778:Tetrazolium Salts; D013844:Thiazoles; D049452:Green Fluorescent Proteins; D001120:Arginine; C022616:thiazolyl blue