Point mutation analysis of the Xenopus laevis RNA polymerase I core promoter.
AUTOR(ES)
Firek, S
RESUMO
The core region of the Xenopus laevis pre-ribosomal RNA promoter was subjected to point mutation analysis. A total of 27 point mutants within a 78 base pair region from -64 to +14, (relative to the start of transcription at +1), were assayed by oocyte microinjection. The results locate the 3' boundary of the core promoter at +4 and the 5' boundary at between -33 and -39 and suggest that this region of the Xenopus promoter is generally similar in organisation to mammalian core promoters. In particular, the conserved guanidine nucleotides at -7 and -16 are clearly essential for promoter function. The data suggest that interactions between the transcription machinery and the promoter occur in four distinct regions around +2 to +4, -7, -17 to -20 and -28 to -33. This particular periodicity of functionally important nucleotides is consistent with a model in which all protein-DNA interactions take place from predominantly one side of the DNA helix.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=330209Documentos Relacionados
- Point mutational analysis of the Xenopus laevis 5S gene promoter.
- Directed semisynthetic point mutational analysis of an RNA polymerase III promoter.
- Effect of intercalating agents on RNA polymerase I promoter selection in Xenopus laevis.
- Linker scanning of the yeast RNA polymerase I promoter.
- Linker scanner mutagenesis of the Xenopus laevis ribosomal gene promoter.
