The presence of a C-1/G+73 pair in a tRNA precursor influences processing and expression in vivo.
To understand whether 5' and 3' structural elements of the region corresponding to the mature tRNA affect the expression of the tRNA, we examined several bacterial genomes for tRNA genes where the expression might be potentially affected by structural elements located outside of the mature tRNA. In Pseudomonas aeruginosa, our analysis suggested that the tRNA(Trp) is transcribed together with a putative stem-loop structure followed by a uridine tract immediately downstream of the tRNA region. This structural element, resembling a Rho-independent transcription terminator, might therefore influence the expression and processing of tRNA(Trp). Moreover, the secondary structure suggested that the discriminator base in the tRNA(Trp) precursor can pair with either the C at position -1, the 3' terminal residue in the 5' leader, or the C immediately 5' of the uridine tract of the putative Rho-independent transcription terminator. Here, we present in vivo data demonstrating the importance of residue -1 and the positioning of the putative transcription terminator for the expression of correctly 5' processed P. aeruginosa tRNA(Trp) in Escherichia coli. Interestingly, we also detected a difference in the appearance of correctly 5' processed P. aeruginosa tRNA(Trp) in E. coli compared to the situation in P. aeruginosa.
Pettersson
B M Fredrik
BM
Department of Cell and Molecular Biology, Box 596, Biomedical Center, SE-751 24 Uppsala, Sweden.
Kirsebom
Leif A
LA
D020029:Base Pairing; D001483:Base Sequence; D004926:Escherichia coli / Q000235:genetics; D015964:Gene Expression Regulation, Bacterial; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic / Q000235:genetics; D011550:Pseudomonas aeruginosa / Q000235:genetics; D012322:RNA Precursors / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D012323:RNA Processing, Post-Transcriptional; D012329:RNA, Bacterial / Q000235:genetics; D012364:RNA, Transfer, Trp / Q000737:chemistry / Q000235:genetics; D013728:Terminator Regions, Genetic
D012322:RNA Precursors; D012329:RNA, Bacterial; D012364:RNA, Transfer, Trp