title: Antisense RNA, fur, iron, and the regulation of iron transport genes in Vibrio anguillarum.
abstract: The negative regulation of the expression of iron transport genes fatA and fatB in Vibrio anguillarum is mediated by a chromosome-encoded Fur protein and a plasmid pJM1-derived antisense RNA (RNAalpha), which is preferentially expressed under iron-rich conditions. In this work, we characterized the RNAalpha promoter region, and by using promoter fusion and rifampicin experiments we were able to demonstrate that iron regulates RNAalpha synthesis posttranscriptionally by stabilizing RNAalpha half-life rather than enhancing transcription initiation. The Fur protein is also essential for RNAalpha synthesis at the transcription initiation level, independently of the iron status of the cell. From experiments assessing the relative contribution of Fur and RNAalpha, we were able to show that RNAalpha may indeed play an important role on the negative regulation of the expression of the iron transport genes under physiological conditions.
authors.affiliation: Department of Molecular Microbiology and Immunology L220, School of Medicine, Oregon Health Sciences University, Portland, Oregon 97201-3098, USA.
authors.forename: Q
authors.initials: Q
authors.lastname: Chen
authors.forename: J H
authors.initials: JH
authors.lastname: Crosa
mesh_terms: D001425:Bacterial Outer Membrane Proteins / Q000235:genetics / Q000378:metabolism; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D001483:Base Sequence; D001693:Biological Transport, Active / Q000235:genetics; D002874:Chromosome Mapping; D004269:DNA, Bacterial / Q000235:genetics; D005798:Genes, Bacterial; D007501:Iron / Q000378:metabolism*; D026901:Membrane Transport Proteins; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D011401:Promoter Regions, Genetic; D016372:RNA, Antisense / Q000096:biosynthesis / Q000235:genetics*; D012329:RNA, Bacterial / Q000096:biosynthesis / Q000235:genetics*; D012097:Repressor Proteins / Q000235:genetics / Q000378:metabolism*; D014158:Transcription, Genetic; D014733:Vibrio / Q000235:genetics* / Q000378:metabolism*
chemical_list: D001425:Bacterial Outer Membrane Proteins; D001426:Bacterial Proteins; D004269:DNA, Bacterial; C071991:FatB protein, Vibrio anguillarum; D026901:Membrane Transport Proteins; D016372:RNA, Antisense; D012329:RNA, Bacterial; D012097:Repressor Proteins; C068477:ferric uptake regulating proteins, bacterial; C071990:FatA protein, bacteria; D007501:Iron