Identification of transcriptionally induced Z-DNA segments in the human c-myc gene.
Using monoclonal antibodies against Z-DNA three AluI restriction fragments of the human c-myc gene were previously found to form Z-DNA in agarose-embedded, metabolically active permeabilized nuclei. The formation of Z-DNA in these fragments was dependent on negative supercoiling generated by transcription of the gene. Here we show which sequence elements of these three AluI restriction fragments adopt the Z conformation upon negative supercoiling. The three fragments (Z1, Z2 and Z3) were inserted in a suitable plasmid vector. Z-DNA forming elements were detected by comparing DEPC reactivity in relaxed circular and supercoiled plasmid DNA. Z1 and Z3 each contained one major Z-DNA forming region 20-25 nucleotides long, whereas Z2 contained two discrete regions 90 nucleotides apart one about 35 nucleotides the other about 20 nucleotides long.
Wölfl
S
S
Massachusetts Institute of Technology, Department of Biology, Cambridge, USA.
Wittig
B
B
Rich
A
A
D001483:Base Sequence; D004247:DNA / Q000737:chemistry*; D015252:Deoxyribonucleases, Type II Site-Specific; D016259:Genes, myc; D006801:Humans; D008968:Molecular Conformation; D008969:Molecular Sequence Data; D010713:Phosphatidylcholines; D010957:Plasmids; D014158:Transcription, Genetic
D010713:Phosphatidylcholines; D004247:DNA; C024669:endodeoxyribonuclease AluI; D015252:Deoxyribonucleases, Type II Site-Specific; C017251:1,2-oleoylphosphatidylcholine