English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

The spacer promoter of the rat rDNA repeat consists of two functional domains: a core (proximal) element that is sufficient for transcription in vitro, and an upstream (distal) promoter element that increases the efficiency of transcription. Two of the transcription factors that interact with the 45S promoter also interact with the spacer promoter. Rat SL-1, is required for transcription of the spacer promoter by heterologous extracts, e.g. human, and rat SF-1 is required for efficient transcription in vitro. Order-of-addition experiments demonstrated that the preinitiation complex formed by these factors on the spacer promoter is not as stable as the complex formed on the 45S promoter. DNase 1 footprinting experiments demonstrated binding sites for rat SL-1 and SF-1 on the distal element of the spacer promoter. The topology of the domains of the spacer promoter may explain both the reduced stability of the preinitiation complex formed on that promoter and the lower efficiency of transcription of that promoter when compared to the 45S promoter.

Interaction of RNA polymerase I transcription factors with a promoter in the nontranscribed spacer of rat ribosomal DNA