DNA superhelicity affects the formation of transcription preinitiation complex on eukaryotic genes differently.
AUTOR(ES)
Mizutani, M
RESUMO
In vitro transcription was reconstituted with HeLa cell transcription factors and RNA polymerase II, which were essentially free from DNA topoisomerase activities. DNA templates with defined negative superhelical densities were tested for transcription activity. Transcription of the Bombyx mori fibroin gene increases and plateaus from templates of increasing superhelicity, and transcription from the adenovirus 2 major late promoter rises and then falls, while transcription of the Drosophila hsp70 gene remains unchanged. Dissection of transcription into pre and post-initiation steps by the use of Sarkosyl reveals that formation of a preinitiation complex on the fibroin gene or the adenovirus 2 major late promoter is slow on relaxed DNA and accelerated by DNA superhelicity. On the contrary, the preinitiation complex assembles rapidly on the hsp70 gene irrespective of DNA topology. As is the case with the fibroin gene promoter, DNA superhelicity appears to facilitate the interaction of transcription factor IID to the adenovirus 2 major late promoter.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=328250Documentos Relacionados
- DNA supercoiling affects in vitro transcription of two maize chloroplast genes differently.
- In vitro transcription of eukaryotic genes is affected differently by the degree of DNA supercoiling.
- Protein-protein interactions in eukaryotic transcription initiation: structure of the preinitiation complex.
- Ribosomal RNA transcription: proteins and DNA sequences involved in preinitiation complex formation.
- Overexpression of c-jun, junB, or junD affects cell growth differently.