Effect of intercalating agents on RNA polymerase I promoter selection in Xenopus laevis.
Open Access
- 1 December 1984
- journal article
- research article
- Published by Taylor & Francis in Molecular and Cellular Biology
- Vol. 4 (12) , 2851-2857
- https://doi.org/10.1128/mcb.4.12.2851
Abstract
We have analyzed the effect of DNA intercalating agents on the transcription signals from two different Xenopus laevis RNA polymerase I promoters. The transcription signal from the promoter for the 7.5-kilobase rRNA precursor (the gene promoter) is unaffected over a large range of intercalating agent concentrations regardless of whether the template is injected plasmid DNA in oocytes, the amplified endogenous nucleoli of oocytes, or the endogenous chromosomes of cultured Xenopus kidney cells. The transcription signal from a closely related promoter located in the spacer DNA between genes (the spacer promoter) ranges between undetectable to equivalent to the gene promoter signal on different templates. The transcription signal from the spacer promoter is also differentially affected by intercalating agents relative to the gene promoter. Depending on the template, these agents can either increase or decrease the transcription signal from the spacer promoter. Fusions between the gene and spacer promoters demonstrate that intercalating agents affect transcription initiation. One explanation for these results is that the degree of supercoiling of the template DNA can differentially inhibit transcription from the spacer promoters. The different effects of intercalating agents on transcription from the spacer promoters of various templates could then be explained as differences in the degree of supercoiling present on these templates initially.This publication has 22 references indexed in Scilit:
- Effect of topological constraint on transcription of ribosomal DNA in Xenopus oocytesJournal of Molecular Biology, 1984
- Spacer regulation of xenopus ribosomal gene transcription: competition in oocytesCell, 1983
- Nested control regions promote Xenopus ribosomal RNA synthesis by RNA polymerase ICell, 1983
- Transcription of DNA injected into Xenopus oocytes is influenced by template topologyNature, 1983
- A transcriptional function for the repetitive ribosomal spacer in Xenopus laevisNature, 1983
- Transcription of cloned Xenopus laevis ribosomal DNA microinjected into Xenopus oocytes, and the identification of an RNA polymerase I promoterCell, 1982
- A mosaicism in the higher order structure of Xenopus oocyte nucleolar chromatin prior to and during ribosomal gene transcriptionCell, 1981
- Expression of sea urchin histone genes in the oocyte of Xenopus laevisJournal of Molecular Biology, 1979
- The transcription of 5 S DNA injected into Xenopus oocytesDevelopmental Biology, 1978
- The degree of unwinding of the DNA helix by ethidiumJournal of Molecular Biology, 1974