Plant tRNA genes: putative soybean genes for tRNAasp and tRNAmet.

We have identified cloned fragments of the soybean genome that hybridize to total soybean tRNA. Five of these clones, chosen at random, have unique patterns of restriction endonuclease sites and contain only a small region that is homologous to tRNA (less than 1 kb of 10-12 kb cloned). Two of the hybridizing fragments were subcloned and regions of about 600 bp including the homologies were sequenced. Each region contains a single putative tRNA gene, for tRNAasp or tRNAmet, surrounded by DNA rich in AT basepairs (68-82%). Neither sequence encodes the amino acid-accepting -CCA terminus. The tRNAasp gene does not contain any intervening sequences, but the tRNAmet gene has an 11-bp sequence in the anticodon loop that would not be expected in the mature tRNA. There appear to be a small number of sequences within the soybean genome that share homology with each of the regions containing a putative tRNA gene.