Molecular cloning of the DAC2/FUS3 gene essential for pheromone-induced G1-arrest of the cell cycle in Saccharomyces cerevisiae

1990 ◽  
Vol 18 (5) ◽  
pp. 395-400 ◽  
Author(s):  
Hiro-aki Fujimura
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Cell Cycle ◽  
Molecular Cloning ◽  
G1 Arrest

Differential transmission of G1 cell cycle arrest and mating signals by Saccharomyces cerevisiae Ste5 mutants in the pheromone pathway

1999 ◽  
Vol 77 (5) ◽  
pp. 459-468
Author(s):  
You-Jeong Choi ◽  
Sun-Hong Kim ◽  
Ki-Sook Park ◽  
Kang-Yell Choi
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Cell Cycle ◽  
Signal Transduction ◽  
Cell Cycle Arrest ◽  
Mitogen Activated Protein Kinase ◽  
Chemical Mutagenesis ◽  
G1 Arrest ◽  
Cycle Arrest ◽  
Isolation And Characterization ◽  
G1 Cell Cycle Arrest

Saccharomyces cerevisiae Ste5 is a scaffold protein that recruits many pheromone signaling molecules to sequester the pheromone pathway from other homologous mitogen-activated protein kinase pathways. G1 cell cycle arrest and mating are two different physiological consequences of pheromone signal transduction and Ste5 is required for both processes. However, the roles of Ste5 in G1 arrest and mating are not fully understood. To understand the roles of Ste5 better, we isolated 150 G1 cell cycle arrest defective STE5 mutants by chemical mutagenesis of the gene. Here, we found that two G1 cell cycle arrest defective STE5 mutants (ste5MD248V and ste5delta-776) retained mating capacity. When overproduced in a wild-type strain, several ste5 mutants also showed different dominant phenotypes for G1 arrest and mating. Isolation and characterization of the mutants suggested separable roles of Ste5 in G1 arrest and mating of S. cerevisiae. In addition, the roles of Asp-248 and Tyr-421, which are important for pheromone signal transduction were further characterized by site-directed mutagenesis studies.Key words: Ste5, Saccharomyces cerevisiae, signal transduction, mating, G1 cell cycle arrest.

scholarly journals Temperature-Sensitive Lethal Pseudorevertants of ste Mutations in Saccharomyces cerevisiae

Genetics ◽  
1987 ◽  
Vol 115 (4) ◽  
pp. 627-636
Author(s):  
Margaret E Katz ◽  
Jill Ferguson ◽  
Steven I Reed
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Cell Cycle ◽  
Complementation Group ◽  
Temperature Sensitive ◽  
G1 Arrest ◽  
Pheromone Response ◽  
Cycle Arrest ◽  
Homogeneous Cell ◽  
Complementation Groups ◽  
Mutant Cells

ABSTRACT A procedure was devised to isolate mutations that could restore conjugational competence to temperature sensitive ste mutants and simultaneously confer temperature-sensitive lethal growth phenotypes. Three such mutations, falling into two complementation groups, were identified on the basis of suppression of ste5 alleles. These same mutations were later shown to be capable of suppressing ste4 and ste7 alleles. Five mutations in a single complementation group were isolated as suppressors of ste2 alleles. None of the mutations described in this study conferred a homogeneous cell cycle arrest phenotype, and all were shown to define complementation groups distinct from those previously identified in studies of cell division cycle (cdc) mutations. In no instance did pseudoreversion appear to be achieved by mutational G1 arrest of ste mutant cells. Instead, it is proposed that the mutations restore conjugation by reestablishing the normal pheromone response.

Mutations in cell division cycle genes CDC36 and CDC39 activate the Saccharomyces cerevisiae mating pheromone response pathway

1990 ◽  
Vol 10 (6) ◽  
pp. 2966-2972
Author(s):  
M de Barros Lopes ◽  
J Y Ho ◽  
S I Reed
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Cell Cycle ◽  
G Protein ◽  
G1 Arrest ◽  
Restrictive Temperature ◽  
Gene Products ◽  
Pheromone Response ◽  
Mating Pheromone ◽  
Pheromone Response Pathway ◽  
Mutational Activation

Conditional mutations in the genes CDC36 and CDC39 cause arrest in the G1 phase of the Saccharomyces cerevisiae cell cycle at the restrictive temperature. We present evidence that this arrest is a consequence of a mutational activation of the mating pheromone response. cdc36 and cdc39 mutants expressed pheromone-inducible genes in the absence of pheromone and conjugated in the absence of a mating pheromone receptor. On the other hand, cells lacking the G beta subunit or overproducing the G alpha subunit of the transducing G protein that couples the receptor to the pheromone response pathway prevented constitutive activation of the pathway in cdc36 and cdc39 mutants. These epistasis relationships imply that the CDC36 and CDC39 gene products act at the level of the transducing G protein. The CDC36 and CDC39 gene products have a role in cellular processes other than the mating pheromone response. A mating-type heterozygous diploid cell, homozygous for either the cdc36 or cdc39 mutation, does not exhibit the G1 arrest phenotype but arrests asynchronously with respect to the cell cycle. A similar asynchronous arrest was observed in cdc36 and cdc39 cells where the pheromone response pathway had been inactivated by mutations in the transducing G protein. Furthermore, cdc36 and cdc39 mutants, when grown on carbon catabolite-derepressing medium, did not arrest in G1 and did not induce pheromone-specific genes at the restrictive temperature.

TOR2 Is Part of Two Related Signaling Pathways Coordinating Cell Growth in Saccharomyces cerevisiae

Genetics ◽  
1998 ◽  
Vol 148 (1) ◽  
pp. 99-112 ◽  
Author(s):  
Stephen B Helliwell ◽  
Isabelle Howald ◽  
Nik Barbet ◽  
Michael N Hall
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Cell Cycle ◽  
Protein Synthesis ◽  
Cell Growth ◽  
Actin Cytoskeleton ◽  
Signaling Pathways ◽  
Growth Defect ◽  
G1 Arrest ◽  
Class A ◽  
Class B

Abstract The Saccharomyces cerevisiae genes TOR1 and TOR2 encode phosphatidylinositol kinase homologs. TOR2 has two essential functions. One function overlaps with TOR1 and mediates protein synthesis and cell cycle progression. The second essential function of TOR2 is unique to TOR2 and mediates the cell-cycle-dependent organization of the actin cytoskeleton. We have isolated temperature-sensitive mutants that are defective for either one or both of the two TOR2 functions. The three classes of mutants were as follows. Class A mutants, lacking only the TOR2-unique function, are defective in actin cytoskeleton organization and arrest within two to three generations as small-budded cells in the G2/M phase of the cell cycle. Class B mutants, lacking only the TOR-shared function, and class C mutants, lacking both functions, exhibit a rapid loss of protein synthesis and a G1 arrest within one generation. To define further the two functions of TOR2, we isolated multicopy suppressors that rescue the class A or B mutants. Overexpression of MSS4, PKC1, PLC1, RHO2, ROM2, or SUR1 suppressed the growth defect of a class A mutant. Surprisingly, overexpression of PLC1 and MSS4 also suppressed the growth defect of a class B mutant. These genes encode proteins that are involved in phosphoinositide metabolism and signaling. Thus, the two functions (readouts) of TOR2 appear to involve two related signaling pathways controlling cell growth.

scholarly journals Mutations in cell division cycle genes CDC36 and CDC39 activate the Saccharomyces cerevisiae mating pheromone response pathway.

1990 ◽  
Vol 10 (6) ◽  
pp. 2966-2972 ◽  
Author(s):  
M de Barros Lopes ◽  
J Y Ho ◽  
S I Reed
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Cell Cycle ◽  
G Protein ◽  
G1 Arrest ◽  
Restrictive Temperature ◽  
Gene Products ◽  
Pheromone Response ◽  
Mating Pheromone ◽  
Pheromone Response Pathway ◽  
Mutational Activation

Conditional mutations in the genes CDC36 and CDC39 cause arrest in the G1 phase of the Saccharomyces cerevisiae cell cycle at the restrictive temperature. We present evidence that this arrest is a consequence of a mutational activation of the mating pheromone response. cdc36 and cdc39 mutants expressed pheromone-inducible genes in the absence of pheromone and conjugated in the absence of a mating pheromone receptor. On the other hand, cells lacking the G beta subunit or overproducing the G alpha subunit of the transducing G protein that couples the receptor to the pheromone response pathway prevented constitutive activation of the pathway in cdc36 and cdc39 mutants. These epistasis relationships imply that the CDC36 and CDC39 gene products act at the level of the transducing G protein. The CDC36 and CDC39 gene products have a role in cellular processes other than the mating pheromone response. A mating-type heterozygous diploid cell, homozygous for either the cdc36 or cdc39 mutation, does not exhibit the G1 arrest phenotype but arrests asynchronously with respect to the cell cycle. A similar asynchronous arrest was observed in cdc36 and cdc39 cells where the pheromone response pathway had been inactivated by mutations in the transducing G protein. Furthermore, cdc36 and cdc39 mutants, when grown on carbon catabolite-derepressing medium, did not arrest in G1 and did not induce pheromone-specific genes at the restrictive temperature.

scholarly journals Identification and Characterization of FAR3, a Gene Required for Pheromone-Mediated G1 Arrest in Saccharomyces cerevisiae

Genetics ◽  
1996 ◽  
Vol 144 (3) ◽  
pp. 905-921 ◽  
Author(s):  
Joe Horecka ◽  
George F Sprague
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Cell Cycle ◽  
Signal Transduction ◽  
Signal Transduction Pathway ◽  
Selection Strategy ◽  
G1 Arrest ◽  
Amino Acid Residues ◽  
Transduction Pathway ◽  
G1 Cyclin ◽  
Cyclin Protein

Abstract In haploid Saccharomyces cerevisiae cells, mating pheromones activate a signal transduction pathway that leads to cell cycle arrest in the G1 phase and to transcription induction of genes that promote conjugation. To identify genes that link the signal transduction pathway and the cell cycle machinery, we developed a selection strategy to isolate yeast mutants specifically defective for G1 arrest. Several of these mutants identified previously known genes, including CLN3, FUS3, and FAR1. In addition, a new gene, FAR3, was identified and characterized. FAR3 encodes a novel protein of 204 amino acid residues that is dispensable for viability. Northern blot experiments indicated that FAR3 expression is constitutive with respect to cell type, pheromone treatment, and cell cycle position. As a first step toward elucidating the mechanism by which Far3 promotes pheromone-mediated G1 arrest, we performed genetic and molecular experiments to test the possibility that Far3 participates in one of the heretofore characterized mechanisms, namely Fus3/Farl-mediated inhibition of Cdc28-Cln kinase activity, G1 cyclin gene repression, and G1, cyclin protein turnover. Our data indicate that Far3 effects G1 arrest by a mechanism distinct from those previously known.

scholarly journals The Global Transcriptional Activator of Saccharomyces cerevisiae, Gcr1p, Mediates the Response to Glucose by Stimulating Protein Synthesis and CLN-Dependent Cell Cycle Progression

Genetics ◽  
2003 ◽  
Vol 165 (3) ◽  
pp. 1017-1029
Author(s):  
Kristine A Willis ◽  
Kellie E Barbara ◽  
Balaraj B Menon ◽  
Jason Moffat ◽  
Brenda Andrews ◽  
...  
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Cell Cycle ◽  
Protein Synthesis ◽  
Cell Cycle Progression ◽  
Transcriptional Activator ◽  
G1 Arrest ◽  
Ribosomal Protein Genes ◽  
Translation Rate ◽  
Cycle Progression ◽  
Protein Mass

Abstract Growth of Saccharomyces cerevisiae requires coordination of cell cycle events (e.g., new cell wall deposition) with constitutive functions like energy generation and duplication of protein mass. The latter processes are stimulated by the phosphoprotein Gcr1p, a transcriptional activator that operates through two different Rap1p-mediated mechanisms to boost expression of glycolytic and ribosomal protein genes, respectively. Simultaneous disruption of both mechanisms results in a loss of glucose responsiveness and a dramatic drop in translation rate. Since a critical rate of protein synthesis (CRPS) is known to mediate passage through Start and determine cell size by modulating levels of Cln3p, we hypothesized that GCR1 regulates cell cycle progression by coordinating it with growth. We therefore constructed and analyzed gcr1Δ cln3Δ and gcr1Δ cln1Δ cln2Δ strains. Both strains are temperature and cold sensitive; interestingly, they exhibit different arrest phenotypes. The gcr1Δ cln3Δ strain becomes predominantly unbudded with 1N DNA content (G1 arrest), whereas gcr1Δ cln1Δ cln2Δ cells exhibit severe elongation and apparent M phase arrest. Further analysis demonstrated that the Rap1p/Gcr1p complex mediates rapid growth in glucose by stimulating both cellular metabolism and CLN transcription.

scholarly journals Slm9, a Novel Nuclear Protein Involved in Mitotic Control in Fission Yeast

Genetics ◽  
2000 ◽  
Vol 155 (2) ◽  
pp. 623-631
Author(s):  
Junko Kanoh ◽  
Paul Russell
Keyword(s):  
Cell Cycle ◽  
Fission Yeast ◽  
Cell Elongation ◽  
Nuclear Protein ◽  
G1 Arrest ◽  
Permissive Temperature ◽  
Cdc2 Kinase ◽  
Synthetic Lethal ◽  
Cycle Arrest ◽  
Novel Protein

Abstract In the fission yeast Schizosaccharomyces pombe, as in other eukaryotic cells, Cdc2/cyclin B complex is the key regulator of mitosis. Perhaps the most important regulation of Cdc2 is the inhibitory phosphorylation of tyrosine-15 that is catalyzed by Wee1 and Mik1. Cdc25 and Pyp3 phosphatases dephosphorylate tyrosine-15 and activate Cdc2. To isolate novel activators of Cdc2 kinase, we screened synthetic lethal mutants in a cdc25-22 background at the permissive temperature (25°). One of the genes, slm9, encodes a novel protein of 807 amino acids. Slm9 is most similar to Hir2, the histone gene regulator in budding yeast. Slm9 protein level is constant and Slm9 is localized to the nucleus throughout the cell cycle. The slm9 disruptant is delayed at the G2-M transition as indicated by cell elongation and analysis of DNA content. Inactivation of Wee1 fully suppressed the cell elongation phenotype caused by the slm9 mutation. The slm9 mutant is defective in recovery from G1 arrest after nitrogen starvation. The slm9 mutant is also UV sensitive, showing a defect in recovery from the cell cycle arrest after UV irradiation.

Sign in / Sign up

Export Citation Format

Share Document