RNA Polymerase I Transcription

The RNA polymerase I transcription machinery.

The rRNAs constitute the catalytic and structural components of the ribosome, the protein synthesis machinery of cells. The level of rRNA synthesis, mediated by Pol I (RNA polymerase I), therefore has a major impact on the life and destiny of a cell. In order to elucidate how cells achieve the stringent control of Pol I transcription, matching the supply of rRNA to demand under different cellul...

CTD kinase I is involved in RNA polymerase I transcription.

RNA polymerase II carboxy terminal domain (CTD) kinases are key elements in the control of mRNA synthesis. Yeast CTD kinase I (CTDK-I), is a non-essential complex involved in the regulation of mRNA synthesis at the level of transcription elongation, pre-mRNA 3' formation and nuclear export. Here, we report that CTDK-I is also involved in ribosomal RNA synthesis. We show that CTDK-I is localized...

Yeast transcription elongation factor Spt5 associates with RNA polymerase I and RNA polymerase II directly.

Spt5 is a transcription factor conserved in all three domains of life. Spt5 homologues from bacteria and archaea bind the largest subunit of their respective RNA polymerases. Here we demonstrate that Spt5 directly associates with RNA polymerase (Pol) I and RNA Pol II in yeast through its central region containing conserved NusG N-terminal homology and KOW domains. Deletion analysis of SPT5 supp...

RNA polymerase II subunit RPB7 is required for RNA polymerase I mediated transcription in Trypanosoma brucei

New model for the yeast RNA polymerase I transcription cycle.

Using an immobilized template assay, we observed two steps in assembly of the yeast RNA polymerase I (Pol I) preinitiation complex: stable binding of upstream activating factor (UAF) followed by recruitment of Pol I-Rrn3p and core factor (CF). Pol I is required for stable association of CF with the promoter and can be recruited in the absence of Rrn3p. Upon transcription initiation, Pol I-Rrn3p...