title: The antiterminator RNA of phage HK022.
abstract: The put sites of phage HK022 increase the processivity of transcription and thereby promote the expression of viral genes that are located downstream of transcription terminators. RNA polymerase molecules that have traversed a put site are converted to a terminator-resistant form by the put transcript. We analyzed the structure and function of put transcripts by determining the effects of put mutations on terminator read-through, and by probing wild-type and mutant put RNAs with structure-specific nucleases. The results support the prediction that the secondary structure of the active transcript consists of two hairpin stems that are separated by a single unpaired base. The identity of bases in certain bulges and internal loops is important for activity, while that of most bases in the terminal loops is not. Many bases in the stems can be replaced with little or no effect on activity provided that base-pairing is maintained.
authors.affiliation: Laboratory of Molecular Genetics, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA.
authors.forename: S
authors.initials: S
authors.lastname: Banik-Maiti
authors.forename: R A
authors.initials: RA
authors.lastname: King
authors.forename: R A
authors.initials: RA
authors.lastname: Weisberg
mesh_terms: D010582:Bacteriophage lambda / Q000235:genetics*; D001482:Base Composition; D001483:Base Sequence; D004279:DNA, Viral / Q000737:chemistry; D012321:DNA-Directed RNA Polymerases / Q000235:genetics / Q000378:metabolism; D004591:Electrophoresis, Polyacrylamide Gel; D015967:Gene Expression Regulation, Viral / Q000235:genetics; D008969:Molecular Sequence Data; D009154:Mutation / Q000235:genetics; D009690:Nucleic Acid Conformation; D012333:RNA, Messenger / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D012367:RNA, Viral / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D006163:Ribonuclease T1 / Q000378:metabolism; D014158:Transcription, Genetic / Q000235:genetics*
chemical_list: D004279:DNA, Viral; D012333:RNA, Messenger; D012367:RNA, Viral; D012321:DNA-Directed RNA Polymerases; D006163:Ribonuclease T1