Dis3, implicated in mitotic control, binds directly to Ran and enhances the GEF activity of RCC1.
Using the two-hybrid method, we isolated a Saccharomyces cerevisiae cDNA encoding a protein homologous to Schizosaccharomyces pombe protein Dis3sp, using as bait, human GTPase Ran. The DIS3 gene is essential for viability and complements S.pombe mutant dis3-54 which is defective in mitosis. Although Dis3sc has no homology to RanBP1, it bound directly to Ran and the S.cerevisiae Ran homologue Cnr1, but not to the S.cerevisiae RCC1 homologue Srm1. Upon binding to Ran with a 1:1 molar ratio, Dis3sc enhanced a nucleotide-releasing activity of RCC1 on Ran. In the presence of Dis3sc, the K(m) of RCC1 on Ran decreased by half, while the kcat was unchanged. In vivo, Dis3sp was present as oligomers of M(r) 670-200 kDa as previously reported, and the 200 kDa oligomer of Dis3sp was found to include Spi1 and Pim1, the S.pombe homologues of Ran and RCC1, respectively. Although the biological function of the heterotrimeric oligomer consisting of Dis3, Spi1 and Pim1 is unknown, our results indicate that Dis3 is a component of the RCC1-Ran pathway.
Noguchi
E
E
Department of Molecular Biology, Graduate School of Medical Science, Kyushu University, Fukuoka, Japan.
Hayashi
N
N
Azuma
Y
Y
Seki
T
T
Nakamura
M
M
Nakashima
N
N
Yanagida
M
M
He
X
X
Mueller
U
U
Sazer
S
S
Nishimoto
T
T
D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000378:metabolism*; D001427:Bacterial Toxins; D018797:Cell Cycle Proteins; D018076:DNA, Complementary / Q000737:chemistry; D004268:DNA-Binding Proteins / Q000378:metabolism*; D029968:Escherichia coli Proteins; D005095:Exoribonucleases; D063326:Exosome Multienzyme Ribonuclease Complex; D005656:Fungal Proteins / Q000378:metabolism*; D019204:GTP-Binding Proteins / Q000378:metabolism*; D020662:Guanine Nucleotide Exchange Factors; D006801:Humans; D007700:Kinetics; D008565:Membrane Proteins; D008938:Mitosis; D008969:Molecular Sequence Data; D008970:Molecular Weight; D020559:Monomeric GTP-Binding Proteins; D009687:Nuclear Proteins / Q000378:metabolism*; D012441:Saccharomyces cerevisiae; D029701:Saccharomyces cerevisiae Proteins; D012568:Schizosaccharomyces; D029702:Schizosaccharomyces pombe Proteins; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D020931:ran GTP-Binding Protein
D001426:Bacterial Proteins; D001427:Bacterial Toxins; D018797:Cell Cycle Proteins; D018076:DNA, Complementary; D004268:DNA-Binding Proteins; D029968:Escherichia coli Proteins; D005656:Fungal Proteins; C080324:GSP1 protein, S cerevisiae; D020662:Guanine Nucleotide Exchange Factors; D008565:Membrane Proteins; D009687:Nuclear Proteins; C062521:RCC1 protein, human; C067050:SRM1 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins; D029702:Schizosaccharomyces pombe Proteins; C071524:HokC protein, E coli; D005095:Exoribonucleases; D063326:Exosome Multienzyme Ribonuclease Complex; C542283:DIS3 protein, S cerevisiae; C542284:dis3 protein, S pombe; D019204:GTP-Binding Proteins; D020559:Monomeric GTP-Binding Proteins; D020931:ran GTP-Binding Protein