title: Two distinct curved DNAs upstream of the light-responsive psbA gene in a cyanobacterium.
abstract: A functional intrinsic DNA curvature, CIT, and potential DNA-binding factors for the basal transcription of psbA2 have been reported in a cyanobacterium, Microcystis aeruginosa K-81 (Asayama et al., Nucleic Acids Res., 30, 4658-4666 (2002)). In this article, we found another novel curved DNA, which was induced by RNA polymerases binding to the promoter region. Circular permutation analyses showed that the curved center of RNA polymerase-induced DNA bending (RIB) lies at approximately the +10 site, referring to the transcription start point as +1, in the RNA polymerase-DNA complex. Regions containing the curved center of RIB and CIT contributed to the basal transcription in vivo and in vitro. These results indicate that the region upstream of K-81 psbA2 has two distinct curved DNAs, CIT (sequence-directed type) and RIB (protein-induced type).
authors.affiliation: Laboratory of Molecular Genetics, School of Agriculture, Ibaraki University, Ami, Inashiki, Ibaraki 300-0393, Japan.
authors.forename: Ganesh Kumar
authors.initials: GK
authors.lastname: Agrawal
authors.forename: Munehiko
authors.initials: M
authors.lastname: Asayama
authors.forename: Makoto
authors.initials: M
authors.lastname: Shirai
mesh_terms: D000458:Cyanobacteria / Q000235:genetics*; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000378:metabolism / Q000494:pharmacology; D012321:DNA-Directed RNA Polymerases / Q000378:metabolism / Q000494:pharmacology; D004591:Electrophoresis, Polyacrylamide Gel / Q000379:methods; D005798:Genes, Bacterial / Q000235:genetics; D009690:Nucleic Acid Conformation; D045332:Photosystem II Protein Complex / Q000235:genetics*; D011401:Promoter Regions, Genetic / Q000235:genetics; D014158:Transcription, Genetic
chemical_list: D004269:DNA, Bacterial; D004268:DNA-Binding Proteins; D045332:Photosystem II Protein Complex; C422369:photosystem II, psbA subunit; D012321:DNA-Directed RNA Polymerases