A rat tRNA gene cluster containing the genes for tRNAProand tRNALys. Analysis of nucleotide sequences of the genes and the surrounding regions

A lambda clone carrying a rat DNA fragment of 11.9 kb was isolated from a rat gene library with total rat tRNA as a probe. Nucleotide sequence analysis revealed that the DNA fragment contained six tRNA genes, three for tRNAPro and three for tRNALys. Of the six genes all but one tRNAPro gene have the same polarity. Each tRNA gene is separated by a DNA region of 0.1 to 3.6 kb. The 5'-flanking regions of the six rat genes in the cluster do not have any significant sequence homology, but in the 3'-flanking region, each gene has a short T cluster, which is supposed to be a transcription termination signal.