title: Ribonuclease E is involved in the processing of 5-S rRNA from a number of rRNA transcription units.
abstract: Strains of Escherichia coli having a thermosensitive RNase E produce a number of 5-S ribosomal RNA precursors at a non-permissive temperature. One of these precursors, 9-S RNA, was reported earlier [Ghora, B.K. and Apirion, D. (1978) Cell, 15, 1055-1066]. Here we show the existence of additional precursors to 5-S rRNA, originating from a number of rRNA genes. All the precursors are very similar in the first 200 nucleotides and the last part of this sequence contains the mature 5-S rRNA. Precursors that contain only these nucleotides (8-S RNA) accumulate. They probably originate from the rrn genes C, D and F which contain trailer tRNAs. The 9-S RNA precursors contain in addition a termination stem and loop structure and are derived from genes which do not contain trailer tRNA (Singh and Apirion, unpublished results). In addition, a 10-S precursor was identified. It contains distal to the 5-S rRNA a trailer tRNA, tRNAAsp, and a transcription termination signal. It is derived from the rrnF gene. The accumulation of an RNA precursor containing an RNase P site in an rne mutant suggests that the efficiency of one RNA processing enzyme depends on the activity of other RNA processing enzymes.
mesh_terms: D001482:Base Composition; D001483:Base Sequence; D055598:Chemical Phenomena; D002621:Chemistry; D004722:Endoribonucleases / Q000378:metabolism*; D004926:Escherichia coli / Q000201:enzymology; D005796:Genes; D009154:Mutation; D009694:Nucleic Acid Precursors / Q000302:isolation & purification*; D010179:Pancreas / Q000201:enzymology; D012322:RNA Precursors; D012335:RNA, Ribosomal / Q000096:biosynthesis* / Q000302:isolation & purification*; D014158:Transcription, Genetic
chemical_list: D009694:Nucleic Acid Precursors; D012322:RNA Precursors; D012335:RNA, Ribosomal; D004722:Endoribonucleases; C022537:ribonuclease E