Chang, TC, Chang CC.
2010.
Detection of G-quadruplexes in cells and investigation of G-quadruplex structure of d(T2AG3)4 in K+ solution by a carbazole derivative: BMVC. Methods Mol Biol. 608:183-206.
AbstractVerification of the existence of quadruplex structure in native human telomeres and determination of the major structure of d(T(2)AG(3))(4) (H24) in K(+) solution are the major questions regarding the structure of human telomeres. We have synthesized a fluorescent probe of 3,6-bis(1-methyl-4-vinylpyridinium)carbazole diiodide (BMVC) that has a very high binding affinity for G-quadruplex H24. BMVC stabilizes quadruplex structures and acts as a sensitive probe to the local environment. Although the circular dichroism patterns of H24 are different in Na(+) and K(+) solutions, similar binding behaviors of BMVC to H24 in these solutions led us to suggest that the major G-quadruplex structure of H24 in K(+) solution is very likely similar to that in Na(+) solution. Of particular interest is the fluorescent band detected at -575 nm in quadruplex H24 and at -545 nm in duplex DNA. In addition, the intensity of BMVC fluorescence increases by two orders of magnitudes upon interaction with either duplex or G-quadruplex DNA. BMVC has a greater binding preference for G-quadruplex H24 than for duplex DNA. Analyzing the BMVC fluorescence at the ends of metaphase chromosomes and other regions of chromosomes allowed us to verify the presence of G-quadruplex structure in human telomeres for the first time. Using fluorescence lifetime imaging microscopy, the longer decay time of BMVC in G-quadruplex H24 than in duplex DNA allowed us to map the G-quadruplex structure in human metaphase chromosomes.
WC, H, TY T, YT C, CC C, ZF W, CL W, TN H, PT L, CT C, JJ L, PJ L, TC C.
2015.
Direct evidence of mitochondrial G-quadruplex DNA by using fluorescent anti-cancer agents. Nucleic Acids Res.. 43(21):10102-13.