title: BC1 RNA: transcriptional analysis of a neural cell-specific RNA polymerase III transcript.
abstract: Rodent BC1 RNA represents the first example of a neural cell-specific RNA polymerase III (Pol III) transcription product. By developing a rat brain in vitro system capable of supporting Pol III-directed transcription, we showed that the rat BC1 RNA intragenic promoter elements, comprising an A box element and a variant B box element, as well as its upstream region, containing octamer-binding consensus sequences and functional TATA and proximal sequence element sites, are necessary for transcription. The BC1 B box, lacking the invariant A residue found in the consensus B boxes of tRNAs, represents a functionally related and possibly distinct promoter element. The transcriptional activity of the BC1 B box element is greatly increased, in both a BC1 RNA and a chimeric tRNA(Leu) gene construct, when the BC1 5' flanking region is present and is appropriately spaced. Moreover, a tRNA consensus B-box sequence can efficiently replace the BC1 B box only if the BC1 upstream region is removed. These interactions, identified only in a homologous in vitro system, between upstream Pol II and intragenic Pol III promoters suggest a mechanism by which the tissue-specific BC1 RNA gene and possibly other Pol III-transcribed genes can be regulated.
authors.affiliation: Fishberg Research Center for Neurobiology, Mount Sinai School of Medicine, New York, New York 10029.
authors.forename: J A
authors.initials: JA
authors.lastname: Martignetti
authors.forename: J
authors.initials: J
authors.lastname: Brosius
mesh_terms: D000818:Animals; D001483:Base Sequence; D002540:Cerebral Cortex / Q000201:enzymology*; D002678:Chimera; D017931:DNA Primers; D004268:DNA-Binding Proteins / Q000096:biosynthesis*; D004926:Escherichia coli / Q000235:genetics; D005091:Exons; D007438:Introns; D007700:Kinetics; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D009474:Neurons / Q000201:enzymology*; D009928:Organ Specificity; D012319:RNA Polymerase II / Q000378:metabolism; D012320:RNA Polymerase III / Q000378:metabolism*; D062085:RNA, Long Noncoding; D022661:RNA, Untranslated; D051381:Rats; D015183:Restriction Mapping; D012261:Ribonucleoproteins / Q000096:biosynthesis*; D020736:Ribonucleoproteins, Small Cytoplasmic; D012689:Sequence Homology, Nucleic Acid; D013698:Templates, Genetic; D014158:Transcription, Genetic
chemical_list: C489663:Bc1 long-non-coding RNA, rat; D017931:DNA Primers; D004268:DNA-Binding Proteins; D062085:RNA, Long Noncoding; D022661:RNA, Untranslated; D012261:Ribonucleoproteins; D020736:Ribonucleoproteins, Small Cytoplasmic; D012319:RNA Polymerase II; D012320:RNA Polymerase III