title: Insights into anti-termination regulation of the hut operon in Bacillus subtilis: importance of the dual RNA-binding surfaces of HutP.
abstract: The anti-termination protein, HutP, regulates the gene expression of the hut (histidine utilization) operon of Bacillus subtilis, by destabilizing the hut terminator RNA located upstream of the coding region encoding l-histidine degradation enzymes. On the basis of biochemical, in vivo and X-ray structural analyses, we now report that HutP uses its dual RNA-binding surfaces to access two XAG-rich regions (sites I and II) within the terminator RNA to mediate the destabilization process. In this process, HutP initiates destabilization at the 5'-end of its mRNA by binding to the first XAG-rich region (site I) and then accesses the second XAG-rich region (site II), located downstream of the stable G-C-rich segment of the terminator stem. By this action, HutP appears to disrupt the G-C-rich terminator stem, and thus prevents premature termination of transcription in the RNA segment preceding the regions encoding for the histidine degradation enzymes.
authors.affiliation: Functional Nucleic Acids Group, Institute for Biological Resources and Functions, National Institute of Advanced Industrial Science and Technology, Central 6, 1-1-1 Higashi, Tsukuba City 305-8566, Japan.
authors.forename: Subash C B
authors.initials: SC
authors.lastname: Gopinath
authors.forename: Dhakshnamoorthy
authors.initials: D
authors.lastname: Balasundaresan
authors.forename: Thirumananseri
authors.initials: T
authors.lastname: Kumarevel
authors.forename: Tomoko S
authors.initials: TS
authors.lastname: Misono
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Mizuno
authors.forename: Penmetcha K R
authors.initials: PK
authors.lastname: Kumar
mesh_terms: D001412:Bacillus subtilis / Q000235:genetics* / Q000378:metabolism; D001426:Bacterial Proteins / Q000737:chemistry* / Q000378:metabolism; D001483:Base Sequence; D001665:Binding Sites; D015964:Gene Expression Regulation, Bacterial; D006639:Histidine / Q000378:metabolism*; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009154:Mutation; D009690:Nucleic Acid Conformation; D009876:Operon; D012333:RNA, Messenger / Q000737:chemistry / Q000378:metabolism; D016601:RNA-Binding Proteins / Q000737:chemistry* / Q000378:metabolism; D013728:Terminator Regions, Genetic
chemical_list: D001426:Bacterial Proteins; D012333:RNA, Messenger; D016601:RNA-Binding Proteins; C064872:antiterminator proteins, Bacteria; D006639:Histidine