title: Analysis of the promoter region of the melanin locus from Streptomyces antibioticus.
abstract: Several approaches were used to study the transcriptional control region of the melanin-production locus (melC) of Streptomyces antibioticus. Filter-binding in combination with exonuclease III protection localized the 3' boundary of a Streptomyces RNA polymerase-binding site predominantly about 39 nucleotides (nt) upstream from the start codon of melC1, the first open reading frame in the melC locus. Deletion of nt 112-197 upstream from the melC1 start codon reduced melC expression to less than 10%, and deletion of nt 28-107 or 28-120 upstream from melC1 totally inactivated melC. High-resolution nuclease S1 mapping identified the in vitro transcriptional start point (tsp) at 33-34 nt upstream from the start codon of melC1. No sequence resembling the E. coli consensus promoter sequence was found in this region, and site-directed mutagenesis of such a sequence located 101-132 nt upstream from melC1 did not influence melC expression. These studies suggest that transcription of melC is principally from a single tsp and is positively regulated by a mechanism that involves sequences 87-163 nt upstream from the tsp.
authors.affiliation: Institute of Biochemistry, National Yang-Ming Medical College, Taipei, Taiwan, Republic of China.
authors.forename: W M
authors.initials: WM
authors.lastname: Leu
authors.forename: S Y
authors.initials: SY
authors.lastname: Wu
authors.forename: J J
authors.initials: JJ
authors.lastname: Lin
authors.forename: S J
authors.initials: SJ
authors.lastname: Lo
authors.forename: Y H
authors.initials: YH
authors.lastname: Lee
mesh_terms: D001483:Base Sequence; D001665:Binding Sites; D002872:Chromosome Deletion; D004269:DNA, Bacterial / Q000235:genetics* / Q000378:metabolism; D012321:DNA-Directed RNA Polymerases / Q000302:isolation & purification / Q000378:metabolism; D004926:Escherichia coli / Q000235:genetics; D008543:Melanins / Q000235:genetics*; D008969:Molecular Sequence Data; D009154:Mutation; D009693:Nucleic Acid Hybridization; D009710:Nucleotide Mapping; D009838:Oligodeoxyribonucleotides / Q000138:chemical synthesis; D010957:Plasmids; D011401:Promoter Regions, Genetic; D012045:Regulatory Sequences, Nucleic Acid; D015183:Restriction Mapping; D012689:Sequence Homology, Nucleic Acid; D013302:Streptomyces / Q000235:genetics*; D013303:Streptomyces antibioticus / Q000235:genetics*; D014158:Transcription, Genetic; D014169:Transformation, Bacterial
chemical_list: D004269:DNA, Bacterial; D008543:Melanins; D009838:Oligodeoxyribonucleotides; D012321:DNA-Directed RNA Polymerases