The preliminary sequence of tRNA^Met_F from Anacystis nidulans compared with other initiator tRNAs

Self-splicing group I intron in cyanobacterial initiator methionine tRNA: evidence for lateral transfer of introns in bacteria.

“…Amplification of cyanobacterial DNA from Xenococcus sp. (ATCC 29373) Figure 6, lane 3) was cloned and sequenced, confirming an uninterrupted anticodon loop identical in sequence to that previously determined for its tRNAfmet (Ecarot-Charrier and Cedergren, 1976). However, PCRs with genomic DNAs of Scytonema hoffmanii (UTEX 2349) and Dermocarpa sp.…”

“…Assuming that the 5' part of the putative tRNA had to match the 3' part of the sequence, and that it would resemble Synechococcus tRNAfMet (Ecarot-Charrier and Cedergren, 1976), we designed primers for amplifying the entire tRNA gene together with its group I intron by the polymerase chain reaction (PCR) ( Figure 6, lane 4). An oligonucleotide primer complementary to the sequence flanking the BglII site ( Figure 3) allowed separate amplification and cloning of the 5' portion of the gene.…”

RNA structure

“…A case of two completely identical tRNA molecules from different sources has finally been noted (Everett & Madison, 1976); tRNAP he from the pea has the same sequence as tRNAP he from wheat germ. Differences between sequences of initiator tRNA molecules in procaryotes and eucaryotes have been described (Ecarot-Charrier & Cedergren, 1976). An interesting study of sequence homologies among the RNA phages Q/?, MS2 and R17 on the one hand and ribosomal RNA's on the other has been carried out by Engelberg & Schoulaker (1976), who propose that the utilization of host proteins or subunits by these phages rests on structural similarities between regions of the RNA molecules that are reflected in the relationships among the sequences.…”

Molecular evidence for the antiquity of group I introns inter-rupting transfer RNA genes in cyanobacteria

“…Porphyra purpurea (Reith and Mullholland 1995), Mesostigma viride (Lemieux et al 2000), Chlorella vulagaris (Wakasugi et al 1997), Nephroselmis olivacea (Turmel et al 1999), Marchantia polymorpha (Shimada and Sugiura 1991) and Pinus thunbergii (Tsudzuki et al 1994) revealed that all lack the intron. The sporadic nature of the intron is also supported the absence of the intron in Synechococcus PCC 6301 (Ecarot-Charrier and Cedergren 1976). Seven of the introns have been identified previously (Paquin et al 1997) and 9 were novel to this study (Table 3.2.1).…”