Cotranscription of 5S rRNA-tRNA(Arg)(ACG) from Brassica napus chloroplasts and processing of their intergenic spacer.
S1 mapping showed that at least a significant portion of the 5S rRNA and tRNA(Arg)(ACG) is co-transcribed in canola chloroplast, making trnR the last gene transcribed in an operon of which the final sequence is 5'-16S-tRNA(Ile)-tRNA(Ala)-23S-4.5S-5S-tRNA(Arg)-3'. Various RNA termini representing RNA processing sites at several parts of the 5S rRNA-tRNA(Arg) area were detected. This gene spacer is substantially conserved among various species compared here, and a secondary structure model for this chloroplast region in canola applies to other plant sequences. The conservation of this intergenic sequence suggests a functional role, possibly by providing recognition structures for endogenous RNases involved in its maturing process.
División de Medicina Molecular, Centro de Investigación Biomédica de Occidente, Instituto Mexicano del Seguro Social, Sierra Mojada 800, Colonia Independencia, AP 3838, 44340, Jalisco, Guadalajara, Mexico. DSLeal@academ01.mty.itesm.mx
D S
DS
Leal-Klevezas
J P
JP
Martínez-Soriano
R N
RN
Nazar
D001483:Base Sequence; D001937:Brassica / Q000235:genetics*; D002736:Chloroplasts / Q000235:genetics*; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D008958:Models, Molecular; D008969:Molecular Sequence Data; D015394:Molecular Structure; D009690:Nucleic Acid Conformation; D012323:RNA Processing, Post-Transcriptional; D018749:RNA, Plant / Q000235:genetics / Q000502:physiology; D012341:RNA, Ribosomal, 5S / Q000235:genetics*; D012347:RNA, Transfer, Arg / Q000737:chemistry / Q000235:genetics*; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D012689:Sequence Homology, Nucleic Acid; D014158:Transcription, Genetic
D004275:DNA, Ribosomal; D018749:RNA, Plant; D012341:RNA, Ribosomal, 5S; D012347:RNA, Transfer, Arg