Direct visualization of individual DNA molecules by fluorescence microscopy: characterization of the factors affecting signal/background and optimization of imaging conditions using YOYO.
A new series of high-affinity cyanine dyes was tested for the visualization of the dynamics of single DNA molecules through a fluorescence microscope. In particular, YOYO-1 (1,1'-(4,4,7,7-tetramethyl-4,7-diazaundecamethylene)- bis-4-[3-methyl-2,3-dihydro-(benzo-1,3-oxazole)- 2-methylidene]-quinolinium tetraiodide) forms a very stable, highly fluorescent complex with double-stranded DNA and dramatically improves the quality of the images. We have characterized the factors affecting the signal/background in the imaging of single DNA molecules by fluorescence microscopy and compared the results obtained using YOYO-1 with those obtained using standard fluorescent dyes like ethidium bromide or acridine orange.
Gurrieri
S
S
Dipartimento di Scienze Chimiche, Università di Catania, Italy. sgurrieri@dipchi.unict.it
Wells
K S
KS
Johnson
I D
ID
Bustamante
C
C
D000165:Acridine Orange; D001583:Benzoxazoles; D004279:DNA, Viral / Q000032:analysis*; D004996:Ethidium; D005456:Fluorescent Dyes; D007091:Image Processing, Computer-Assisted; D008856:Microscopy, Fluorescence; D011806:Quinolinium Compounds
D001583:Benzoxazoles; D004279:DNA, Viral; D005456:Fluorescent Dyes; D011806:Quinolinium Compounds; C075296:1,1'-((4,4,7,7-tetramethyl)-4,7-diazaundecamethylene)bis-4-(3-methyl-2,3-dihydro(benzo-1,3-oxazole)-2-methylidene)quinolinium; D004996:Ethidium; D000165:Acridine Orange