title: Initiation of rrn transcription in chloroplasts of Euglena gracilis bacillaris.
abstract: The site of initiation of chloroplast rRNA synthesis was determined by S1-mapping and by sequencing primary rRNA transcripts specifically labeled at their 5'-end. Transcription initiates at a single site 53 nucleotides upstream of the 5'-end of the mature 16S rRNA under all growth conditions examined. The initiation site is within a DNA sequence that is highly homologous to and probably derived from a tRNA gene-region located elsewhere in the chloroplast genome. A nearly identical sequence (102 of 103 nucleotides) is present near the replication origin. The near identity of the two sequences suggests a common mode for control of transcription of the rRNA genes and initiation of chloroplast DNA replication. The related sequence in the tRNA gene-region does not appear to serve as a transcript initiation site.
authors.affiliation: Department of Biology, University of Michigan, Ann Arbor 48109.
authors.forename: P
authors.initials: P
authors.lastname: McGarvey
authors.forename: R B
authors.initials: RB
authors.lastname: Helling
authors.forename: J Y
authors.initials: JY
authors.lastname: Lee
authors.forename: D R
authors.initials: DR
authors.lastname: Engelke
authors.forename: M R
authors.initials: MR
authors.lastname: el-Gewely
mesh_terms: D000818:Animals; D001483:Base Sequence; D002736:Chloroplasts / Q000378:metabolism*; D004720:Endonucleases; D005056:Euglena gracilis / Q000235:genetics*; D008969:Molecular Sequence Data; D009876:Operon; D012315:RNA Caps; D012335:RNA, Ribosomal / Q000235:genetics*; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D015719:Single-Strand Specific DNA and RNA Endonucleases; D014158:Transcription, Genetic
chemical_list: D012315:RNA Caps; D012335:RNA, Ribosomal; D012336:RNA, Ribosomal, 16S; D004720:Endonucleases; D015719:Single-Strand Specific DNA and RNA Endonucleases