BINDING OF 4',6-DIAMIDINO-2-PHENYLINDOLE (DAPI) TO AT REGIONS OF DNA - EVIDENCE FOR AN ALLOSTERIC CONFORMATIONAL CHANGE

被引:131
作者
ERIKSSON, S [1 ]
KIM, SK [1 ]
KUBISTA, M [1 ]
NORDEN, B [1 ]
机构
[1] CHALMERS UNIV TECHNOL, DEPT PHYS CHEM, S-41296 GOTHENBURG, SWEDEN
关键词
D O I
10.1021/bi00063a009
中图分类号
Q5 [生物化学]; Q7 [分子生物学];
学科分类号
071010 ; 081704 ;
摘要
The interaction of 4',6-diamidino-2-phenylindole (DAPI) with several double-helical poly- and oligonucleotides has been studied in solution using optical spectroscopic techniques: flow linear dichroism (LD), induced circular dichroism (CD), and fluorescence spectroscopy. In AT-rich sequences, where DAPI is preferentially bound, LD indicates that the molecule is edgewise inserted into the minor groove at an angle of approximately 45-degrees to the helix axis. This binding geometry is found for very low as well as quite high binding ratios. The concluded geometry is in agreement with that of the DAPI complex in a crystal with the Drew-Dickerson dodecamer, and the DAPI complex with this dodecamer in solution is verified to have an ICD spectrum similar to that of the complex with [poly(dA-dT)]2 at low binding ratios. The observation of two types of CD spectra characteristic for the binding of DAPI to DNA, and also for the interaction with [poly(dA-dT)]2, demonstrates that the first binding mode, despite its low apparent abundance (a few percent), is not due to a specific DNA site. The effect may be explained in terms of an allosteric binding such that when DAPI molecules bind contiguously to the AT sequence the conformation of the latter is changed. The new conformation, which according to LD appears to be stiffer than normal B-form DNA, is responsible for the second type of induced CD spectrum in the DAPI chromophore. Although the spectroscopic results indicate a change of DNA conformation, consistent with an allosteric binding model, they do not explicitly require any cooperativity, but accidental neighbors could also explain the data.
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页码:2987 / 2998
页数:12
相关论文
共 50 条
[1]   THE ELECTRONICALLY EXCITED-STATES OF 2-PHENYLINDOLE [J].
ALBINSSON, B ;
ERIKSSON, S ;
LYNG, R ;
KUBISTA, M .
CHEMICAL PHYSICS, 1991, 151 (01) :149-157
[2]   A MOLECULAR APPROACH TO 4',6-DIAMIDINE-2-PHENYLINDOLE (DAPI) PHOTOPHYSICAL BEHAVIOR AT DIFFERENT PH VALUES [J].
BARCELLONA, ML ;
GRATTON, E .
BIOPHYSICAL CHEMISTRY, 1991, 40 (03) :223-229
[3]  
BARCELLONA ML, 1990, EUR BIOPHYS J, V17, P315
[4]   C-BANDING WITH SPECIFIC FLUORESCENT DNA-LIGANDS - A NEW APPROACH TO CONSTITUTIVE HETEROCHROMATIN HETEROGENEITY [J].
BELLA, JL ;
GOSALVEZ, J .
BIOTECHNIC & HISTOCHEMISTRY, 1991, 66 (01) :44-52
[5]   DIFFERENT HOECHST-33342 AND DAPI FLUORESCENCE OF THE HUMAN Y-CHROMOSOME IN BIVARIATE FLOW KARYOTYPES [J].
BERNHEIM, A ;
MIGLIERINA, R .
HUMAN GENETICS, 1989, 83 (02) :189-193
[6]  
BIERZYNSKI A, 1978, STUD BIOPHYS, V67, P57
[7]   DENDRITIC GROWTH OF DAPI-ACCUMULATING AMACRINE CELLS IN THE RETINA OF THE GOLDFISH [J].
BROWN, RN ;
HITCHCOCK, PF .
DEVELOPMENTAL BRAIN RESEARCH, 1989, 50 (01) :123-128
[8]   A TIME-RESOLVED FLUORESCENCE STUDY OF 4',6'-DIAMIDINE-2-PHENYLINDOLE DIHYDROCHLORIDE BINDING TO POLYNUCLEOTIDES [J].
CAVATORTA, P ;
MASOTTI, L ;
SZABO, AG .
BIOPHYSICAL CHEMISTRY, 1985, 22 (1-2) :11-16
[9]   USE OF DAPI CYTOFLUOROMETRIC ANALYSIS OF CELLULAR DNA CONTENT TO DIFFERENTIATE SPITZ NEVUS FROM MALIGNANT-MELANOMA [J].
CHI, HI ;
ISHIBASHI, Y ;
SHIMA, A ;
MIHARA, I ;
OTSUKA, F .
JOURNAL OF INVESTIGATIVE DERMATOLOGY, 1990, 95 (02) :154-157
[10]  
DANN O, 1971, LIEBIGS ANN CHEM, V749, P68