Net1 stimulates RNA polymerase I transcription and regulates nucleolar structure independently of controlling mitotic exit.
The budding yeast RENT complex, consisting of at least three proteins (Net1, Cdc14, Sir2), is anchored to the nucleolus by Net1. RENT controls mitotic exit, nucleolar silencing, and nucleolar localization of Nop1. Here, we report two new functions of Net1. First, Net1 directly binds Pol I and stimulates rRNA synthesis both in vitro and in vivo. Second, Net1 modulates nucleolar structure by regulating rDNA morphology and proper localization of multiple nucleolar antigens, including Pol I. Importantly, we show that the nucleolar and previously described cell cycle functions of the RENT complex can be uncoupled by a dominant mutant allele of CDC14. The independent functions of Net1 link a key event in the cell cycle to nucleolar processes that are fundamental to cell growth.
Shou
W
W
Division of Biology, California Institute of Technology, Pasadena 91125, USA.
Sakamoto
K M
KM
Keener
J
J
Morimoto
K W
KW
Traverso
E E
EE
Azzam
R
R
Hoppe
G J
GJ
Feldman
R M
RM
DeModena
J
J
Moazed
D
D
Charbonneau
H
H
Nomura
M
M
Deshaies
R J
RJ
D000818:Animals; D015152:Blotting, Northern; D018797:Cell Cycle Proteins / Q000235:genetics / Q000378:metabolism; D002466:Cell Nucleolus / Q000502:physiology* / Q000648:ultrastructure; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism; D006655:Histone Deacetylases / Q000235:genetics / Q000378:metabolism; D017404:In Situ Hybridization, Fluorescence; D008856:Microscopy, Fluorescence; D008938:Mitosis / Q000502:physiology*; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism*; D009690:Nucleic Acid Conformation; D010641:Phenotype; D035463:Pol1 Transcription Initiation Complex Proteins; D017027:Protein Tyrosine Phosphatases; D012318:RNA Polymerase I / Q000378:metabolism*; D012335:RNA, Ribosomal / Q000096:biosynthesis / Q000235:genetics; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D020718:Ribonucleoproteins, Small Nucleolar; D012441:Saccharomyces cerevisiae / Q000502:physiology; D029701:Saccharomyces cerevisiae Proteins; D038281:Silent Information Regulator Proteins, Saccharomyces cerevisiae; D056565:Sirtuin 2; D037761:Sirtuins; D013172:Spores, Fungal / Q000502:physiology; D013696:Temperature; D015534:Trans-Activators / Q000235:genetics / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism; D014158:Transcription, Genetic
C074860:CDC14 protein, S cerevisiae; D018797:Cell Cycle Proteins; D005656:Fungal Proteins; C064793:NOP1 protein, S cerevisiae; C119300:Net1 protein, S cerevisiae; D009687:Nuclear Proteins; D035463:Pol1 Transcription Initiation Complex Proteins; D012335:RNA, Ribosomal; C101161:RRN3 protein, S cerevisiae; D011993:Recombinant Fusion Proteins; D020718:Ribonucleoproteins, Small Nucleolar; D029701:Saccharomyces cerevisiae Proteins; D038281:Silent Information Regulator Proteins, Saccharomyces cerevisiae; D015534:Trans-Activators; D014157:Transcription Factors; D012318:RNA Polymerase I; D017027:Protein Tyrosine Phosphatases; C087778:SIR2 protein, S cerevisiae; D056565:Sirtuin 2; D037761:Sirtuins; D006655:Histone Deacetylases