Skip to main content
PMC home page
Molecular and Cellular Biology logoLink to Molecular and Cellular Biology
. 1987 May;7(5):1900–1905. doi: 10.1128/mcb.7.5.1900

A 12-base-pair sequence is an essential element of the ribosomal gene terminator in Xenopus laevis.

P Labhart, R H Reeder
PMCID: PMC365294  PMID: 3600650

Abstract

rRNA transcription in Xenopus laevis terminates near a 7-base-pair (bp) conserved sequence (T3 box) located 200 bp upstream of the site of transcription initiation for the adjacent gene promoter. We present evidence here that a 12-bp element containing the T3 box is an essential part of the terminator. Using an oocyte injection assay, we found that the 12-bp element (but not the T3 box alone) severely reduced the amount of RNA detectable at sites downstream from itself and that the T3 box within the 12-bp element was required to specify the formation of correct 3' ends. This requirement for the 12-bp element was also seen in pulse-label experiments by using a homogenate of oocyte nuclei, but the present data did not allow us to determine the exact mechanism by which the 12-bp element acts. Removal of the T3 region from its normal location allowed a significant amount of readthrough transcripts to accumulate, indicating that additional sequences may be required for complete terminator function.

Full text

PDF
1904

Images in this article

1902Image
on p.1902
1903Image
on p.1903
1903Image
on p.1903

Selected References

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

  1. Boseley P., Moss T., Mächler M., Portmann R., Birnstiel M. Sequence organization of the spacer DNA in a ribosomal gene unit of Xenopus laevis. Cell. 1979 May;17(1):19–31. doi: 10.1016/0092-8674(79)90291-5. [DOI] [PubMed] [Google Scholar]
  2. De Winter R. F., Moss T. The ribosomal spacer in Xenopus laevis is transcribed as part of the primary ribosomal RNA. Nucleic Acids Res. 1986 Aug 11;14(15):6041–6051. doi: 10.1093/nar/14.15.6041. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Delli Bovi P., Basilico C. Isolation of a rearranged human transforming gene following transfection of Kaposi sarcoma DNA. Proc Natl Acad Sci U S A. 1987 Aug;84(16):5660–5664. doi: 10.1073/pnas.84.16.5660. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Furlong J. C., Forbes J., Robertson M., Maden B. E. The external transcribed spacer and preceding region of Xenopus borealis rDNA: comparison with the corresponding region of Xenopus laevis rDNA. Nucleic Acids Res. 1983 Dec 10;11(23):8183–8196. doi: 10.1093/nar/11.23.8183. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Grummt I., Kuhn A., Bartsch I., Rosenbauer H. A transcription terminator located upstream of the mouse rDNA initiation site affects rRNA synthesis. Cell. 1986 Dec 26;47(6):901–911. doi: 10.1016/0092-8674(86)90805-6. [DOI] [PubMed] [Google Scholar]
  6. Grummt I., Maier U., Ohrlein A., Hassouna N., Bachellerie J. P. Transcription of mouse rDNA terminates downstream of the 3' end of 28S RNA and involves interaction of factors with repeated sequences in the 3' spacer. Cell. 1985 Dec;43(3 Pt 2):801–810. doi: 10.1016/0092-8674(85)90253-3. [DOI] [PubMed] [Google Scholar]
  7. Grummt I., Rosenbauer H., Niedermeyer I., Maier U., Ohrlein A. A repeated 18 bp sequence motif in the mouse rDNA spacer mediates binding of a nuclear factor and transcription termination. Cell. 1986 Jun 20;45(6):837–846. doi: 10.1016/0092-8674(86)90558-1. [DOI] [PubMed] [Google Scholar]
  8. Henderson S., Sollner-Webb B. A transcriptional terminator is a novel element of the promoter of the mouse ribosomal RNA gene. Cell. 1986 Dec 26;47(6):891–900. doi: 10.1016/0092-8674(86)90804-4. [DOI] [PubMed] [Google Scholar]
  9. Hipskind R. A., Reeder R. H. Initiation of ribosomal RNA chains in homogenates of oocyte nuclei. J Biol Chem. 1980 Aug 25;255(16):7896–7906. [PubMed] [Google Scholar]
  10. Labhart P., Reeder R. H. Characterization of three sites of RNA 3' end formation in the Xenopus ribosomal gene spacer. Cell. 1986 May 9;45(3):431–443. doi: 10.1016/0092-8674(86)90329-6. [DOI] [PubMed] [Google Scholar]
  11. Labhart P., Reeder R. H. Xenopus ribosomal gene enhancers function when inserted inside the gene they enhance. Nucleic Acids Res. 1985 Dec 20;13(24):8999–9009. doi: 10.1093/nar/13.24.8999. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Maxam A. M., Gilbert W. Sequencing end-labeled DNA with base-specific chemical cleavages. Methods Enzymol. 1980;65(1):499–560. doi: 10.1016/s0076-6879(80)65059-9. [DOI] [PubMed] [Google Scholar]
  13. McStay B., Reeder R. H. A termination site for Xenopus RNA polymerase I also acts as an element of an adjacent promoter. Cell. 1986 Dec 26;47(6):913–920. doi: 10.1016/0092-8674(86)90806-8. [DOI] [PubMed] [Google Scholar]
  14. Moss T. A transcriptional function for the repetitive ribosomal spacer in Xenopus laevis. Nature. 1983 Mar 17;302(5905):223–228. doi: 10.1038/302223a0. [DOI] [PubMed] [Google Scholar]
  15. Moss T., Boseley P. G., Birnstiel M. L. More ribosomal spacer sequences from Xenopus laevis. Nucleic Acids Res. 1980 Feb 11;8(3):467–485. doi: 10.1093/nar/8.3.467. [DOI] [PMC free article] [PubMed] [Google Scholar]
  16. Moss T., Mitchelson K., de Winter R. The promotion of ribosomal transcription in eukaryotes. Oxf Surv Eukaryot Genes. 1985;2:207–250. [PubMed] [Google Scholar]
  17. Norris K., Norris F., Christiansen L., Fiil N. Efficient site-directed mutagenesis by simultaneous use of two primers. Nucleic Acids Res. 1983 Aug 11;11(15):5103–5112. doi: 10.1093/nar/11.15.5103. [DOI] [PMC free article] [PubMed] [Google Scholar]
  18. Sollner-Webb B., Wilkinson J. A., Roan J., Reeder R. H. Nested control regions promote Xenopus ribosomal RNA synthesis by RNA polymerase I. Cell. 1983 Nov;35(1):199–206. doi: 10.1016/0092-8674(83)90222-2. [DOI] [PubMed] [Google Scholar]

Articles from Molecular and Cellular Biology are provided here courtesy of Taylor & Francis

RESOURCES