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. 1986 Aug 11;14(15):6041–6051. doi: 10.1093/nar/14.15.6041

The ribosomal spacer in Xenopus laevis is transcribed as part of the primary ribosomal RNA.

R F De Winter, T Moss
PMCID: PMC311620  PMID: 3018668

Abstract

S1 mapping of Xenopus laevis ribosomal RNA transcripts, both in oocyte microinjection experiments and in vivo, shows that all but 212 bp of the so-called "non-transcribed" spacer (NTS) of the ribosomal DNA repeat is transcribed as part of the primary ribosomal transcript. The 40S pre-ribosomal RNA (pre-rRNA) is therefore a processing intermediate. The primary ribosomal transcript co-terminates with the previously described spacer transcripts [Moss], at a site 213 bp upstream of the 40S pre-rRNA initiation site. This mode of transcription suggests a simple mechanism for the recently proposed phenomenon of "readthrough-enhancement", [Moss et al, Moss], where readthrough transcription from an upstream gene may enhance transcription of a gene immediately downstream in the tandem ribosomal repeat.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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