Regulation of Ribosomal RNA Production by RNA Polymerase I: Does Elongation Come First?

Autor: Olivier Gadal, Benjamin Albert, Isabelle Léger-Silvestre, Jorge Perez-Fernandez
Rok vydání: 2012
Předmět:
Zdroj: Genetics Research International, Vol 2012 (2012)
Genetics Research International
ISSN: 2090-3162
2090-3154
Popis: Ribosomal RNA (rRNA) production represents the most active transcription in the cell. Synthesis of the large rRNA precursors (35–47S) can be achieved by up to 150 RNA polymerase I (Pol I) enzymes simultaneously transcribing each rRNA gene. In this paper, we present recent advances made in understanding the regulatory mechanisms that control elongation. Built-in Pol I elongation factors, such as Rpa34/Rpa49 in budding yeast and PAF53/CAST in humans, are instrumental to the extremely high rate of rRNA production per gene. rRNA elongation mechanisms are intrinsically linked to chromatin structure and to the higher-order organization of the rRNA genes (rDNA). Factors such as Hmo1 in yeast and UBF1 in humans are key players in rDNA chromatin structurein vivo. Finally, elongation factors known to regulate messengers RNA production by RNA polymerase II are also involved in rRNA production and work cooperatively with Rpa49in vivo.
Databáze: OpenAIRE