title: Particle tracking of intracellular trafficking of octaarginine-modified liposomes: a comparative study with adenovirus.
abstract: It is previously reported that octaarginine (R8)-modified liposome (R8-Lip) was taken up via macropinocytosis, and subsequently delivered to the nuclear periphery. In the present study, we investigated the mechanism for the cytoplasmic transport of R8-Lips, comparing with that for adenovirus. Treatment with microtubule-disruption reagent (nocodazole) inhibited the transfection activity of plasmid DNA (pDNA)-encapsulating R8-Lip more extensively than that of adenovirus. The directional transport of R8-Lips along green fluorescent protein (GFP)-tagged microtubules was observed; however, the velocity was slower than those for adenovirus or endosomes that were devoid of R8-Lips. These directional motions were abrogated in R8-Lips by nocodazole treatment, whereas adenovirus continued to undergo random motion. This finding suggests that the nuclear access of R8-Lip predominantly involves microtubule-dependent transport, whereas an apparent diffusive motion is also operative in nuclear access of adenovirus. Furthermore, quantum dot-labeled pDNA underwent directional motion concomitantly with rhodamine-labeled lipid envelopes, indicating that the R8-Lips were subject to microtubule-dependent transport in the intact form. Dual particle tracking of carriers and endosomes revealed that R8-Lip was directionally transported, associated with endosomes, whereas this occurs after endosomal escape in adenovirus. Collectively, the findings reported herein indicate that vesicular transport is a key factor in the cytoplasmic transport of R8-Lips.
authors.affiliation: Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo City, Japan. akita@pharm.hokudai.ac.jp
authors.forename: Hidetaka
authors.initials: H
authors.lastname: Akita
authors.forename: Kaoru
authors.initials: K
authors.lastname: Enoto
authors.forename: Tomoya
authors.initials: T
authors.lastname: Masuda
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Mizuguchi
authors.forename: Tomomi
authors.initials: T
authors.lastname: Tani
authors.forename: Hideyoshi
authors.initials: H
authors.lastname: Harashima
mesh_terms: D000256:Adenoviridae / Q000235:genetics / Q000378:metabolism*; D000970:Antineoplastic Agents / Q000494:pharmacology; D003593:Cytoplasm / Q000378:metabolism; D011992:Endosomes / Q000378:metabolism; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D006367:HeLa Cells; D006801:Humans; D008081:Liposomes / Q000737:chemistry / Q000378:metabolism*; D008870:Microtubules / Q000235:genetics / Q000378:metabolism; D015739:Nocodazole / Q000494:pharmacology; D009842:Oligopeptides / Q000737:chemistry*; D010873:Pinocytosis; D014162:Transfection
chemical_list: D000970:Antineoplastic Agents; D008081:Liposomes; D009842:Oligopeptides; C448619:octaarginine; D049452:Green Fluorescent Proteins; D015739:Nocodazole