Sequence analyses of RNA polymerase III control elements. (A) Sequences of all of the tRNA genes from each species were aligned and then subjected to Sequence Logo (Schneider and Stephens 1990). Position 1 reflects the first nucleotide of mature tRNA. The A and B boxes are indicated as are the positions of the anticodon (ac) and intron plus variable stem (i/v). (*) The third position of the A box (see text), which shows variable conservation. (B) The sequences upstream of the first nucleotide in all of the tRNA genes are aligned and then subjected to Sequence Logo to evaluate conservation of TATA-box sequences in the different yeasts. (C) Plot of fractional abundance of the oligo(dT) length of the first encountered transcription terminator relative to the total tRNA gene pool for each yeast and for human tRNAs predicted by the same method.
