Interaction of psoralen-derivatized oligodeoxyribonucleoside methylphosphonates with synthetic DNA containing a promoter for T7 RNA polymerase.
The interaction of 4'-N(2-aminoethyl)aminomethyl-4,5',8-trimethylpsoralen-modified oligonucleoside methylphosphonates with synthetic ds-DNA containing a T7 RNA polymerase promoter was studied. The oligomers effectively crosslinked with either coding or noncoding ss-DNA when irradiated at 365 nm, but not with ds-DNA. The extent of the crosslinking reaction, which was complete within 16 min: (a) reached its maximum at an oligomer concentration of 3 microM; (b) remained constant below the Tm of the duplex and then rapidly decreased; and (c) appeared to depend upon the sequence surrounding the psoralen crosslinking site. An oligomer crosslinked to the template strand inhibited transcription by T7 RNA polymerase whereas an oligomer crosslinked to the non-template strand had only a small inhibitory effect. Oligomers did not crosslink to ds-DNA undergoing transcription nor did they inhibit the transcription reaction.
Lee
B L
BL
Division of Biophysics, School of Hygiene and Public Health, Johns Hopkins University, Baltimore, MD 21205.
Blake
K R
KR
Miller
P S
PS
D001483:Base Sequence; D003432:Cross-Linking Reagents / Q000494:pharmacology*; D004277:DNA, Single-Stranded / Q000187:drug effects / Q000235:genetics*; D012321:DNA-Directed RNA Polymerases / Q000378:metabolism*; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics; D011564:Furocoumarins / Q000031:analogs & derivatives / Q000494:pharmacology; D007700:Kinetics; D008969:Molecular Sequence Data; D009838:Oligodeoxyribonucleotides / Q000494:pharmacology*; D011401:Promoter Regions, Genetic / Q000187:drug effects*; D013604:T-Phages / Q000201:enzymology / Q000235:genetics; D013816:Thermodynamics; D014158:Transcription, Genetic / Q000187:drug effects*; D014307:Trioxsalen / Q000031:analogs & derivatives / Q000494:pharmacology
D003432:Cross-Linking Reagents; D004277:DNA, Single-Stranded; D011564:Furocoumarins; D009838:Oligodeoxyribonucleotides; C021992:dideoxyribonucleoside methylphosphonates; D012321:DNA-Directed RNA Polymerases; D014307:Trioxsalen