title: Synthesis and splice-redirecting activity of branched, arginine-rich peptide dendrimer conjugates of peptide nucleic acid oligonucleotides.
abstract: Arginine-rich cell-penetrating peptides have found excellent utility in cell and in vivo models for enhancement of delivery of attached charge-neutral PNA or PMO oligonucleotides. We report the synthesis of dendrimeric peptides containing 2- or 4-branched arms each having one or more R-Ahx-R motifs and their disulfide conjugation to a PNA705 splice-redirecting oligonucleotide. Conjugates were assayed in a HeLa pLuc705 cell assay for luciferase up-regulation and splicing redirection. Whereas 8-Arg branched peptide-PNA conjugates showed poor activity compared to a linear (R-Ahx-R)(4)-PNA conjugate, 2-branched and some 4-branched 12 and 16 Arg peptide-PNA conjugates showed activity similar to that of the corresponding linear peptide-PNA conjugates. Many of the 12- and 16-Arg conjugates retained significant activity in the presence of serum. Evidence showed that biological activity in HeLa pLuc705 cells of the PNA conjugates of branched and linear (R-Ahx-R) peptides is associated with an energy-dependent uptake pathway, predominantly clathrin-dependent, but also with some caveolae dependence.
authors.affiliation: Medical Research Council, Laboratory of Molecular Biology, Cambridge, United Kingdom.
authors.forename: Amer F
authors.initials: AF
authors.lastname: Saleh
authors.forename: Andrey
authors.initials: A
authors.lastname: Arzumanov
authors.forename: Rachida
authors.initials: R
authors.lastname: Abes
authors.forename: David
authors.initials: D
authors.lastname: Owen
authors.forename: Bernard
authors.initials: B
authors.lastname: Lebleu
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Gait
mesh_terms: D020816:Amino Acid Motifs; D001120:Arginine; D001483:Base Sequence; D050091:Dendrimers / Q000138:chemical synthesis* / Q000737:chemistry / Q000378:metabolism*; D006367:HeLa Cells; D006801:Humans; D020135:Peptide Nucleic Acids / Q000235:genetics / Q000378:metabolism*; D010455:Peptides / Q000138:chemical synthesis* / Q000737:chemistry / Q000378:metabolism*; D021381:Protein Transport; D012326:RNA Splicing
chemical_list: D050091:Dendrimers; D020135:Peptide Nucleic Acids; D010455:Peptides; D001120:Arginine