title: Smart magnetic fluorescent nanoparticle imaging probes to monitor microRNAs.
abstract: An imaging system that can be used to evaluate the expression levels of microRNAs during neuronal development can provide noninvasive information for investigating a variety of biological phenomena related to microRNAs (miRNAs, miRs). Herein, the development of a novel imaging platform to monitor intracellular miR124a during neuronal differentiation is reported using rhodamine-coated cobalt ferrite magnetic fluorescent (MF) nanoparticles linked to a quenching molecular system containing an miR124a binding sequence (MF-miR124a beacon). During neuronal differentiation, in vitro fluorescence signals of the MF-miR124a beacon are significantly increased under conditions where miR124a is highly expressed, and dramatically return to the original quenched fluorescence after anti-miR124a treatment. In vivo fluorescence images show enhanced fluorescence signals in mice with P19 cells within a poly-L-lactic acid scaffold after induction of neuronal differentiation. In addition, magnetic resonance (MR) images provide in vivo tracking of cells containing the MF-miR124a beacon. These studies represent the first step toward the use of nanotechnological imaging of mature miRNA, and this technique could be used for cellular tracking with a MR imaging system as well as for simultaneous monitoring of the miRNA expression pattern in vivo.
authors.affiliation: Department of Nuclear Medicine, Seoul National University College of Medicine, 28 Yongon-dong, Jongno-gu, Seoul 110-744, Korea.
authors.forename: Do Won
authors.initials: DW
authors.lastname: Hwang
authors.forename: In Chan
authors.initials: IC
authors.lastname: Song
authors.forename: Dong Soo
authors.initials: DS
authors.lastname: Lee
authors.forename: Soonhag
authors.initials: S
authors.lastname: Kim
mesh_terms: D000818:Animals; D002460:Cell Line; D008280:Magnetics; D008422:Materials Testing; D051379:Mice; D015336:Molecular Probe Techniques; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure; D036103:Nanotechnology / Q000379:methods*; D009474:Neurons / Q000378:metabolism*; D010316:Particle Size; D012333:RNA, Messenger / Q000378:metabolism*
chemical_list: D012333:RNA, Messenger