Selective dinucleotide-primed in vitro transcription of a cloned fragment of cauliflower mosaic virus DNA is dependent on a limited region of the viral genome.
We have previously shown that plant RNA polymerase II preferentially forms ternary transcription complexes on a cloned fragment of the cauliflower mosaic virus genome in the presence of a particular dinucleotide/purine NTP combination (ApG + ATP). This preferential interaction is observed when the viral sequences are present on a discrete circular molecule. Deletion of a 205-bases-pair region abolishes this selectivity. The deleted region contains a considerable number of symmetrical or repeating elements. The use of nuclease S1 as a probe shows that this region contains a homopurine-homopyrimidine sequence which is extremely sensitive to this enzyme, indicating its capacity to adopt a non-B DNA conformation. A possible alternative structure of these sequences, which may explain the preferential interaction with the RNA polymerase, is presented.
D001483:Base Sequence; D002872:Chromosome Deletion; D003001:Cloning, Molecular; D004279:DNA, Viral / Q000378:metabolism*; D012321:DNA-Directed RNA Polymerases / Q000378:metabolism; D015226:Dinucleoside Phosphates; D004720:Endonucleases / Q000378:metabolism; D009029:Mosaic Viruses / Q000235:genetics*; D009690:Nucleic Acid Conformation; D009841:Oligonucleotides / Q000378:metabolism*; D015719:Single-Strand Specific DNA and RNA Endonucleases; D014158:Transcription, Genetic
D004279:DNA, Viral; D015226:Dinucleoside Phosphates; D009841:Oligonucleotides; D012321:DNA-Directed RNA Polymerases; D004720:Endonucleases; D015719:Single-Strand Specific DNA and RNA Endonucleases