Table 4. Yeast tRNA families and their genes


  tRNA species 


Number of functional genes  


tDNA anti-codon tRNA anticodon 



Probable codon preferences d) Remarks on variant tRNA or tDNA sequences  


1 Ala1 11 AGC IGC GCU; GCC  
2 Ala2 5 TGC *UGC GCA; GCG?  
3 Arg1 1 CCT CCU AGG  
4 Arg2 6 ACG ICG CGU; CGC; CGA?  
5 Arg3 


11 TCT mcm5UCU AGA Four dimeric(Arg-Asp) genes; no gene for a variant tRNA(Arg3) in aS288C
6 Arg4 1 CCG *CCG CGG  
7 Asn 10 GTT GUU AAU; AAC  
8 Asp 15 GTC GUC GAU; GAC Four dimeric(Arg-Asp) genes
9 Cys 4 GCA GCA UGU; UGC  
10 Gln1 





These variants to tRNA(Gln1) have 3 alternate bases in AC stem

11 Gln2 1 CTG *CUG CAG Essential gene, closely related to Gln1.
12 Glu3 14 TTC mcm5s2UUC GAA  
13 Glu4 2 CTC *CUC GAG  
14 Gly1 16 GCC GCC GGU; GGC  
15 Gly2 3 TCC NCC GGA  
16 Gly3 2 CCC *CCC GGG  
17 His2 7 GTG GUG CAU; CAC  
18 Ile1 2 (i) TAT *UAU AUA Probably one variant gene
19 Ile2 13 AAT IAU AUU; AUC  
20 Leu1 3 (i) TAG UAG CUA; CUG? CUU; CUC; UUA; UUG Variant intron sequences in one gene copy
21 Leu3 10(i) CAA m5CAA UUG Variant introns in five gene copies
22 Leu4 7 TAA NAA UUA; UUG  
23 Leu5 1 GAG *GAG CUU; (CUC?)  
24 Lys1 14 CTT CUU AAG Probably two variant genes
25 Lys2 7 (i) TTT cmnm5UmUU AAA Variant intron in one gene copy
26 Meti 5 CAT CAU AUG  
27 Met3 5 CAT CAU AUG Variant tRNA(Met3) observed in other strain
28 Phe 8 (i) GAA GmAA UUU; UUC Variant intron sequences
  Phe1a 2 (i) GAA GmAA UUU; UUC tRNA(Phe1a) has alternate bases in acceptor stem; genes have variant introns
29 Pro1 10 (i) TGG ?UGG CCA; CCG? One variant gene; variant introns in 5 gene copies
30 Pro2 2 AGG prob. IGG CCU; CCC  
31 Ser2 11 AGA IGA UCU; UCC  
32 Ser3 4 (i) GCT *GCU AGU; AGC 2 genes with variant AC loop (cf. Text)
33 Ser4 3 TGA ?UGA UCA  
34 Ser5 1 (i) CGA *CGA UCG  
35 Thr1a 11 AGT IGU ACU; ACC  
36 Thr2 1 CGT *CGU ACG  
37 Thr3 4 TGT *UGU ACA Probably one variant gene
38 Trp 6 (i) CCA CmCA UGG  
39 Tyr 8 (i) GTA GyA UAU; UAC Variant introns in 3 gene copies
40 Val1a 13 AAC IAC GUU; GUC  
  Val1b 1 AAC IAC GUU; GUC Variant tRNA(Val1) gene 
41 Val2a 2 TAC ncm5UAC GUA  
42 Val2b 2 CAC CAC GUG  
  Total 274        


a) As far as possible, designations of the tRNA species follow those in the literature. For simplicity, isoaccepting tRNA species that have not been sequenced earlier or were predicted from the gene sequences have been numbered arbitrarily.
b) (i) indicates the presence of intron sequences.
c) Nomenclature for modified bases is as in Steinberg, S., Misch, A. and Sprinzl, M.(1993) Nucleic Acids Res. 21, 3001-3015 ( An asterisk indicates that this base has been deduced from the DNA sequence but that further information on whether this a modified or unmodified base is lacking because the corresponding tRNA has not been sequenced.
d) Exact in vivo codon recognitions have been determined experimentally in only a few cases. Largely, we follow the conventions proposed in Guthrie, C. and Abelson, J. (1982); in: Strathern, J.N., Jones, E.W. and Broach, J.R. (eds.) CSH Laboratory Press, pp.487-528. Question marks refer to codons not yet assigned to particular tRNAs.
e) Variants giving rise to suppressor tRNAs are not listed here; for details, see the tables of tRNA genes in
A catalogue with detailed references is presented in Table 4a.