Association of the GTP-binding protein Gtr1p with Rpc19p, a shared subunit of RNA polymerase I and III in yeast Saccharomyces cerevisiae

Yuko Todaka; Yonggang Wang; Kosuke Tashiro; Nobutaka Nakashima; Takeharu Nishimoto; Takeshi Sekiguchi

doi:10.1534/genetics.105.042366

Association of the GTP-binding protein Gtr1p with Rpc19p, a shared subunit of RNA polymerase I and III in yeast Saccharomyces cerevisiae

Genetics. 2005 Aug;170(4):1515-24. doi: 10.1534/genetics.105.042366. Epub 2005 Jun 3.

Authors

Yuko Todaka¹, Yonggang Wang, Kosuke Tashiro, Nobutaka Nakashima, Takeharu Nishimoto, Takeshi Sekiguchi

Affiliation

¹ Department of Molecular Biology, Graduate School of Medical Science, Kyushu University, Fukuoka 812-8582, Japan.

Abstract

Yeast Gtr1p and its human homolog RRAG A belong to the Ras-like small G-protein superfamily and genetically interact with RCC1, a guanine nucleotide exchange factor for Ran GTPase. Little is known regarding the function of Gtr1p. We performed yeast two-hybrid screening using Gtr1p as the bait to find interacting proteins. Rpc19p, a shared subunit of RNA polymerases I and III, associated with Gtr1p. The association of Gtr1p with Rpc19p occurred in a GTP-form-specific manner. RRAG A associated with RPA16 (human Rpc19p homolog) in a GTP-form-specific manner, suggesting that the association is conserved during evolution. Ribosomal RNA and tRNA synthesis were reduced in the gtr1Delta strain expressing the GDP form of Gtr1p, but not the GTP form of Gtr1p. Gel-filtration studies revealed an accumulation of the smaller Rpc19p-containing complex, but not of A135, in the gtr1Delta strain. Here, we propose that Gtr1p is involved in RNA polymerase I and III assembly by its association with Rpc19p and could be a mediator that links growth regulatory signals with ribosome biogenesis.

Publication types

Comparative Study
Research Support, Non-U.S. Gov't

MeSH terms

DNA-Directed RNA Polymerases / genetics
DNA-Directed RNA Polymerases / metabolism
Electrophoresis, Polyacrylamide Gel
Fungal Proteins / genetics
Fungal Proteins / metabolism*
GTP-Binding Proteins / genetics
GTP-Binding Proteins / metabolism*
Genes, Fungal
Genetic Markers
Glutathione Transferase / metabolism
Glycoside Hydrolases / analysis
Monomeric GTP-Binding Proteins / genetics
Monomeric GTP-Binding Proteins / metabolism*
Protein Subunits / chemistry
RNA Polymerase I / chemistry*
RNA Polymerase III / chemistry*
RNA, Ribosomal / biosynthesis
Recombinant Fusion Proteins / metabolism
Saccharomyces cerevisiae / genetics
Saccharomyces cerevisiae / metabolism*
Saccharomyces cerevisiae Proteins / genetics
Saccharomyces cerevisiae Proteins / metabolism*
Two-Hybrid System Techniques

Substances

Fungal Proteins
Genetic Markers
Gtr1 protein, S cerevisiae
Protein Subunits
RNA, Ribosomal
Recombinant Fusion Proteins
Saccharomyces cerevisiae Proteins
Glutathione Transferase
DNA-Directed RNA Polymerases
RNA Polymerase I
RNA Polymerase III
Rpc19p protein, S cerevisiae
Glycoside Hydrolases
beta-galactanase
GTP-Binding Proteins
Monomeric GTP-Binding Proteins