Nucleotide sequence of a human 5S rRNA gene.

A gene for human 5S rRNA has been cloned and sequenced. The gene was isolated on a 638 bp fragment (Fig. 1) from human placenta DNA by digestion with BamHI and Sad and cloning into a Bluescnpt M13 plasmid. A ^P-labelled SP6-transcript of a mouse pseudogene was used as a probe. The fragment has a restriction pattern identical to the pattern of the majority of human 5S rRNA genes, which are found in tandem repeats of 2.3 kb (unpublished results). The gene is transcribed in a HeLa cell extract. Comparative sequence analysis reveals only limited homologies to flanking regions of other eucaryotic 5S rRNA genes In Fig. 2 is shown the comparison to position 1 to 6 0 of a hamster 5S rRNA gene (1) and the Xenopus laevis somatic and oocyte 5S rRNA genes (2, 3) The A and G at positions 1 5 and —14, which are conserved between human and Xenopus, is part of a Xenopus element suggested to bind an upstream stimulatory factor (4). ACKNOWLEDGEMENTS