Sequence elements essential for function of the Xenopus laevis ribosomal DNA enhancers.
Open Access
- 1 October 1988
- journal article
- research article
- Published by Taylor & Francis in Molecular and Cellular Biology
- Vol. 8 (10), 4282-4288
- https://doi.org/10.1128/mcb.8.10.4282
Abstract
The intergenic spacer region of the Xenopus laevis ribosomal DNA contains multiple elements which are either 60 or 81 base pairs long. Clusters of these elements have previously been shown to act as position- and distance-independent enhancers on an RNA polymerase I promoter when located in cis. By a combination of deletion and linker scanner mutagenesis we show that the sequences essential for enhancer function are located within a 56-base-pair region that is present in both the 60- and 81-base-pair repeats. Within the 56-base-pair region one linker scanner mutation was found to be relatively neutral, suggesting that each enhancer element may be composed of two smaller domains. Each 56-base-pair region appears to be an independent enhancer with multiple enhancers being additive in effect. We review the current evidence concerning the mechanism of action of these enhancers.This publication has 19 references indexed in Scilit:
- A complex array of sequences enhances ribosomal transcription in Xenopus laevisJournal of Molecular Biology, 1987
- Characterization of three sites of RNA 3$prime; end formation in the Xenopus ribosomal gene spacerCell, 1986
- Spacer promoters are essential for efficient enhancement of X. laevis ribosomal transcriptionCell, 1986
- Mechanisms of nucleolar dominance in animals and plants.The Journal of cell biology, 1985
- The mechanism of nucleolar dominance in xenopus hybridsCell, 1984
- Enhancer-like properties of the 60/81 bp elements in the ribosomal gene spacer of Xenopus laevisCell, 1984
- Spacer sequences regulate transcription of ribosomal gene plasmids injected into Xenopus embryosCell, 1983
- A transcriptional function for the repetitive ribosomal spacer in Xenopus laevisNature, 1983
- The nucleotide sequence of the initiation and termination sites for ribosomal rna transcription in x. laevisCell, 1979
- Restriction analysis of the nontranscribed spacers of Xenopus laevis ribosomal DNACell, 1977