TY  - JOUR
AU  - Iacovella, Maria G
AU  - Golfieri, Cristina
AU  - Massari, Lucia F
AU  - Busnelli, Sara
AU  - Pagliuca, Cinzia
AU  - Dal Maschio, Marianna
AU  - Infantino, Valentina
AU  - Visintin, Rosella
AU  - Mechtler, Karl
AU  - Ferreira-Cerca, Sébastien
AU  - De Wulf, Peter
TI  - Rio1 promotes rDNA stability and downregulates RNA polymerase I to ensure rDNA segregation.
JO  - Nature Communications
VL  - 6
IS  - 1
SN  - 2041-1723
CY  - [London]
PB  - Nature Publishing Group UK
M1  - DZNE-2020-07623
SP  - 6643
PY  - 2015
AB  - The conserved protein kinase Rio1 localizes to the cytoplasm and nucleus of eukaryotic cells. While the roles of Rio1 in the cytoplasm are well characterized, its nuclear function remains unknown. Here we show that nuclear Rio1 promotes rDNA array stability and segregation in Saccharomyces cerevisiae. During rDNA replication in S phase, Rio1 downregulates RNA polymerase I (PolI) and recruits the histone deacetylase Sir2. Both interventions ensure rDNA copy-number homeostasis and prevent the formation of extrachromosomal rDNA circles, which are linked to accelerated ageing in yeast. During anaphase, Rio1 downregulates PolI by targeting its subunit Rpa43, causing PolI to dissociate from the rDNA. By stimulating the processing of PolI-generated transcripts at the rDNA, Rio1 allows for rDNA condensation and segregation in late anaphase. These events finalize the genome transmission process. We identify Rio1 as an essential nucleolar housekeeper that integrates rDNA replication and segregation with ribosome biogenesis.
KW  - Anaphase: genetics
KW  - Chromosome Segregation: genetics
KW  - DNA Replication: genetics
KW  - DNA, Ribosomal: metabolism
KW  - DNA-Binding Proteins: genetics
KW  - Down-Regulation
KW  - Protein-Serine-Threonine Kinases: genetics
KW  - RNA Polymerase I: genetics
KW  - S Phase: genetics
KW  - Saccharomyces cerevisiae
KW  - Saccharomyces cerevisiae Proteins: genetics
KW  - Silent Information Regulator Proteins, Saccharomyces cerevisiae: genetics
KW  - Sirtuin 2: genetics
KW  - DNA, Ribosomal (NLM Chemicals)
KW  - DNA-Binding Proteins (NLM Chemicals)
KW  - Rpa43 protein, S cerevisiae (NLM Chemicals)
KW  - Saccharomyces cerevisiae Proteins (NLM Chemicals)
KW  - Silent Information Regulator Proteins, Saccharomyces cerevisiae (NLM Chemicals)
KW  - Protein-Serine-Threonine Kinases (NLM Chemicals)
KW  - Rio1 protein, S cerevisiae (NLM Chemicals)
KW  - RNA Polymerase I (NLM Chemicals)
KW  - SIR2 protein, S cerevisiae (NLM Chemicals)
KW  - Sirtuin 2 (NLM Chemicals)
LB  - PUB:(DE-HGF)16
C6  - pmid:25851096
DO  - DOI:10.1038/ncomms7643
UR  - https://pub.dzne.de/record/141301
ER  -