Table 1.
Characteristics of permuted tRNA genes in unicellular algae and archaea.
| Organism | Permuted tRNA (anticodon) | Type (junction) | Intervening seq. (bp) | Intron (BHB, position, bp) |
|---|---|---|---|---|
| RED ALGA | ||||
| C. merolae | Leu(TAA) | I (20/21) | 10 | hBHBh', 37/38, 21 |
| Gln(CTG) | II (37/38) | 31 | No | |
| Leu(CAG) | II (37/38) | 9 | No | |
| Thr(CGT) | II (37/38) | 31 | No | |
| Thr(AGT) | II (37/38) | 24 | No | |
| Gly(CCC) | II (37/38) | 7 | no h, 55/56, 13 | |
| Gly(CCC) | II (37/38) | 7 | no h, 55/56, 13 | |
| iMet(CAT) | III (50/51) | 74 | No | |
| Ala(TGC) | IV (59/60) | 8 | No | |
| Arg(CCT) | IV (59/60) | 23 | hBHBh', 14/15, 27 | |
| Lys(TTT) | IV (59/60) | 38 | No | |
| GREEN ALGA | ||||
| O. lucimarinus | Leu (TAA) | II (37/38) | 25 | No |
| Ser(CGA) | II (37/38) | 12 | No | |
| Ser(TGA) | II (37/38) | 13 | no H, 27/28, 56 | |
| Cys(GCA) | II (37/38) | 26 | No | |
| O. tauri | Ser (CGA)* | V (15/16) | 17 | No |
| Ser(CGA) | II (37/38) | 28 | No | |
| Ser(TGA) | II (37/38) | 33 | No | |
| Arg(TCT) | II (37/38) | 11 | No | |
| Asn(GTT) | II (37/38) | 22 | No | |
| Cys(GCA) | II (37/38) | 38 | No | |
| M. pusilla | Ser (GCT) | II (37/38) | 15 | No |
| Ser(CGA) | II (37/38) | 19 | No | |
| Ser(AGA) | II (37/38) | 64 | No | |
| iMet(CAT) | II (37/38) | 47 | No | |
| Leu(TAA) | II (37/38) | 20 | No | |
| Cys(GCA) | II (37/38) | 12 | No | |
| M.sp RCC299 | Ser (CGA) | II (37/38) | 16 | No |
| Ser(TGA) | II (37/38) | 12 | No | |
| iMet(CAT) | II (37/38) | 12 | No | |
| CHLORARACHNIOPHYTE ALGA | ||||
| B. natans | Ser (AGA) | II (37/38) | 5 | No |
| (nucleomorph) | Ser(CGA) | II (37/38) | 5 | No |
| CRENARCHAEA | ||||
| T. pendens | iMet (CAT) | IV (59/60) | 7 | no H, 37/38, 15 |
| Tyr(GTA) | IV (59/60) | 1 | no H, 37/38, 59 | |
Each gene is identified by the amino acid with which the tRNA is charged. Classification of permuted tRNAs (types I–V) is based on the location of the junction between the 5 ′-half and the 3 ′-half in the inferred secondary structure for pre-tRNAs. The length (bp, base pair) of sequence encoding for the intervening sequence and the presence of an intron are indicated. In C. merolae, two distinct genes that produce identical mature tRNA sequences encode tRNAGly(CCC). iMet and eMet mean initiator and elongator tRNAMet(CAT), respectively. The asterisk indicates that the sequence of this tRNA is a typical, and experimental analysis would be preferable.