title: Detection of undegraded oligonucleotides in living sea urchin eggs by fluorescence resonance energy transfer.
abstract: A method was investigated for monitoring the integrity of oligonucleotides in solution and in cells using fluorescence resonance energy transfer (FRET) between two different fluorochromes attached to a single oligonucleotide. A 10-meric oligodeoxynucleotide labeled with fluorescein at its 5'-end and with rhodamine X at its 3'-end (F-ODN-R) was used. The oligomer had a specific absorption spectrum with peaks at 497 nm and 586 nm, which corresponded to fluorescein and rhodamine X, respectively. When excited at 494 nm, F-ODN-R had a specific fluorescence spectrum with peaks at 523 nm and 610 nm. The digestion of F-ODN-R with an endonuclease caused the increase in light intensity at 523 nm and the decrease at 610 nm. To examine effects in vivo, living sea urchin eggs were injected with a solution of F-ODN-R and excited with blue light at 470-490 nm. Two fluorescent images, a green image at 520-560 nm and a red image at above 580 nm, were obtained when a single egg was viewed under a fluorescence microscope. Eggs injected with the digested F-ODN-R emitted only green fluorescence. These results indicated that the integrity of oligonucleotides can be estimated in living cells by monitoring FRET after double-labeling of the oligonucleotides with fluorescein and rhodamine X.
authors.affiliation: Tsukuba Research Laboratory, Hamamatsu Photonics K. K., Tsukuba Science City, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Uchiyama
authors.forename: K
authors.initials: K
authors.lastname: Hirano
authors.forename: M
authors.initials: M
authors.lastname: Kashiwasake-Jibu
authors.forename: B
authors.initials: B
authors.lastname: Mullah
authors.forename: A
authors.initials: A
authors.lastname: Andrus
authors.forename: K
authors.initials: K
authors.lastname: Taira
mesh_terms: D000818:Animals; D001483:Base Sequence; D005260:Female; D019793:Fluorescein; D005452:Fluoresceins; D005456:Fluorescent Dyes; D008845:Microinjections; D008856:Microscopy, Fluorescence; D009841:Oligonucleotides / Q000032:analysis / Q000737:chemistry / Q000378:metabolism*; D010063:Ovum / Q000378:metabolism*; D012235:Rhodamines; D012617:Sea Urchins / Q000378:metabolism; D013050:Spectrometry, Fluorescence
chemical_list: D005452:Fluoresceins; D005456:Fluorescent Dyes; D009841:Oligonucleotides; D012235:Rhodamines; D019793:Fluorescein