title: Stable stem-loop and cruciform DNA structures: isolation of mutants with rearrangements of the palindromic sequence at the simian virus 40 replication origin.
abstract: With the objective of generating DNA molecules that form stable stem-loop structures or cruciform structures in solution, we have altered the palindromic sequence at the Simian Virus 40 (SV40) replication origin. These alterations include: deletion of 18 of the 27 base pairs (bp) in the 13-bp inverted repeat; deletion of 26 of the 27 bp; substitution of the entire 27 bp with a totally different 26-bp sequence containing a 13-bp inverted repeat; and substitution of the 27 bp with an 8-bp sequence containing a 4-bp inverted repeat. The DNA from these mutants was purified. Mutant DNAs were hybridized to wild-type SV40 DNA or to each other, and the heteroduplexes were purified. The predicted structures were verified by S1 and restriction endonuclease digestion. The mutants - the heteroduplexes have not been tested - are capable of complementing tsA mutants and/or transforming mouse cells.
mesh_terms: D001345:Autoradiography; D002472:Cell Transformation, Viral; D004261:DNA Replication; D004262:DNA Restriction Enzymes; D004279:DNA, Viral / Q000032:analysis*; D004587:Electrophoresis, Agar Gel; D004591:Electrophoresis, Polyacrylamide Gel; D009154:Mutation; D009693:Nucleic Acid Hybridization; D010957:Plasmids; D012091:Repetitive Sequences, Nucleic Acid; D013539:Simian virus 40 / Q000235:genetics*; D014779:Virus Replication
chemical_list: D004279:DNA, Viral; D004262:DNA Restriction Enzymes