The Saccharomyces cerevisiae CKS1 gene, a homolog of the Schizosaccharomyces pombe suc1+ gene, encodes a subunit of the Cdc28 protein kinase complex

The Saccharomyces cerevisiae gene CDC28 encodes a protein kinase required for cell cycle initiation. In an attempt to identify genes encoding proteins that interact with the Cdc28 protein kinase, high-copy plasmid suppressors of a temperature-sensitive cdc28 mutation were isolated. One such suppressor, CKS1, was found to encode an 18-kilodalton protein that shared a high degree of homology with the suc1+ protein (p13) of Schizosaccharomyces pombe (67% amino acid sequence identity). Disruption of the chromosomal CKS1 gene conferred a G1 arrest phenotype similar to that of cdc28 mutants. The presence of the 18-kilodalton Cks1 protein in yeast lysates was demonstrated by using Cks-1 specific antiserum. Furthermore, the Cks1 protein was shown to be physically associated with active forms of the Cdc28 protein kinase. These data suggest that Cks1 is an essential component of the Cdc28 protein kinase complex.

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Two homologous zinc finger genes identified by multicopy suppression in a SNF1 protein kinase mutant of Saccharomyces cerevisiae

Molecular and Cellular Biology ◽

10.1128/mcb.13.7.3872-3881.1993 ◽

1993 ◽

Vol 13 (7) ◽

pp. 3872-3881

Author(s):

F Estruch ◽

M Carlson

Keyword(s):

Saccharomyces Cerevisiae ◽

Protein Kinase ◽

Zinc Finger ◽

Zinc Finger Protein ◽

Wilms Tumor ◽

Temperature Sensitive ◽

Carbon Utilization ◽

Functional Roles ◽

Multicopy Suppressor ◽

Finger Protein

The MSN2 gene was selected as a multicopy suppressor in a temperature-sensitive SNF1 protein kinase mutant of Saccharomyces cerevisiae. MSN2 encodes a Cys2His2 zinc finger protein related to the yeast MIG1 repressor and to mammalian early growth response and Wilms' tumor zinc finger proteins. Deletion of MSN2 caused no phenotype. A second similar zinc finger gene, MSN4, was isolated, and deletion of both genes caused phenotypic defects related to carbon utilization. Overexpression of the zinc finger regions was deleterious to growth. LexA-MSN2 and LexA-MSN4 fusion proteins functioned as strong transcriptional activators when bound to DNA. Functional roles of this zinc finger protein family are discussed.

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MKK1 and MKK2, which encode Saccharomyces cerevisiae mitogen-activated protein kinase-kinase homologs, function in the pathway mediated by protein kinase C

Molecular and Cellular Biology ◽

10.1128/mcb.13.5.3076-3083.1993 ◽

1993 ◽

Vol 13 (5) ◽

pp. 3076-3083

Author(s):

K Irie ◽

M Takase ◽

K S Lee ◽

D E Levin ◽

H Araki ◽

...

Keyword(s):

Saccharomyces Cerevisiae ◽

Protein Kinase C ◽

Protein Kinase ◽

Map Kinase ◽

Protein Kinases ◽

Cell Lysis ◽

Yeast Cells ◽

Temperature Sensitive ◽

Kinase C ◽

Mitogen Activated Protein

The PKC1 gene of Saccharomyces cerevisiae encodes a homolog of mammalian protein kinase C that is required for normal growth and division of yeast cells. We report here the isolation of the yeast MKK1 and MKK2 (for mitogen-activated protein [MAP] kinase-kinase) genes which, when overexpressed, suppress the cell lysis defect of a temperature-sensitive pkc1 mutant. The MKK genes encode protein kinases most similar to the STE7 product of S. cerevisiae, the byr1 product of Schizosaccharomyces pombe, and vertebrate MAP kinase-kinases. Deletion of either MKK gene alone did not cause any apparent phenotypic defects, but deletion of both MKK1 and MKK2 resulted in a temperature-sensitive cell lysis defect that was suppressed by osmotic stabilizers. This phenotypic defect is similar to that associated with deletion of the BCK1 gene, which is thought to function in the pathway mediated by PCK1. The BCK1 gene also encodes a predicted protein kinase. Overexpression of MKK1 suppressed the growth defect caused by deletion of BCK1, whereas an activated allele of BCK1 (BCK1-20) did not suppress the defect of the mkk1 mkk2 double disruption. Furthermore, overexpression of MPK1, which encodes a protein kinase closely related to vertebrate MAP kinases, suppressed the defect of the mkk1 mkk2 double mutant. These results suggest that MKK1 and MKK2 function in a signal transduction pathway involving the protein kinases encoded by PKC1, BCK1, and MPK1. Genetic epistasis experiments indicated that the site of action for MKK1 and MKK2 is between BCK1 and MPK1.

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The Saccharomyces cerevisiae SRK1 gene, a suppressor of bcy1 and ins1, may be involved in protein phosphatase function

Molecular and Cellular Biology ◽

10.1128/mcb.11.6.3369-3373.1991 ◽

1991 ◽

Vol 11 (6) ◽

pp. 3369-3373

Author(s):

R B Wilson ◽

A A Brenner ◽

T B White ◽

M J Engler ◽

J P Gaughran ◽

...

Keyword(s):

Saccharomyces Cerevisiae ◽

Protein Kinase ◽

Cyclic Amp ◽

Protein Phosphatase ◽

Shuttle Vector ◽

Temperature Sensitive ◽

Protein Kinase Activity ◽

Dependent Protein Kinase ◽

Cycle Arrest ◽

Dependent Protein

The Saccharomyces cerevisiae SRK1 gene, when expressed on a low-copy shuttle vector, partially suppresses the phenotype associated with elevated levels of cyclic AMP-dependent protein kinase activity and suppresses the temperature-sensitive cell cycle arrest of the ins1 mutant. SRK1 is located on chromosome IV, 3 centimorgans from gcn2. A mutant carrying a deletion mutation in srk1 is viable. SRK1 encodes a 140-kDa protein with homology to the dis3+ protein from Schizosaccharomyces pombe. The ability of SRK1 to alleviate partially the defects caused by high levels of cyclic AMP-dependent protein kinase and the similarity of its encoded protein to dis3+ suggest that SRK1 may have a role in protein phosphatase function.

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Regulation of p105weel and p34cdc2 during meiosis in Schizosaccharomyces pombe

Biochemistry and Cell Biology ◽

10.1139/o92-154 ◽

1992 ◽

Vol 70 (10-11) ◽

pp. 1088-1096 ◽

Cited By ~ 7

Author(s):

Maleki Daya-Makin ◽

Philippe Szankasi ◽

Liren Tang ◽

Diana MacRae ◽

Steven L. Pelech

Keyword(s):

Protein Kinase ◽

Schizosaccharomyces Pombe ◽

Thermal Inactivation ◽

State Level ◽

Fold Increase ◽

Histone H1 ◽

Temperature Sensitive ◽

Restrictive Temperature ◽

Nutritional Conditions ◽

Tyrosyl Phosphorylation

Temperature-sensitive pat1 mutants of the fission yeast Schizosaccharomyces pombe can be induced to undergo meiosis at the restrictive temperature, irrespective of the mat1 configuration and the nutritional conditions. Using a combination of exit from stationary phase and thermal inactivation of the 52-kilodalton protein kinase that is encoded by the pat1 (also called ran1) gene, highly synchronous meiotic cultures were obtained. Synthesis and tyrosyl phosphorylation of p34cdc2 was evident during meiotic G1 and S phases. During this period there was increased expression of p105wee1, a protein kinase implicated in the tyrosyl phosphorylation of p34cdc2. Following a relatively brief G2 period, during which a reduction in the steady-state level of p105wee1 occurred, there was an approximately 19-fold increase in the histone H1 phosphotransferase activity of p34cdc2. Only a single peak of histone H1 kinase activation was observed, which implies that unlike meiosis in amphibians and echinoderms, p34cdc2 is functional only during one of the meiotic divisions in S. pombe, presumably meiosis II. Stimulation of the kinase activity of p34cdc2 was associated with its tyrosyl dephosphorylation. This is analogous to mitotic M phase and suggests parallels in the mechanism of activation of p34cdc2 during mitosis and one of the meiotic divisions in S. pombe.Key words: wee1, cdc2, ran1, cell cycle, meiosis.

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Conservation of function and regulation within the Cdc28/cdc2 protein kinase family: characterization of the human Cdc2Hs protein kinase in Saccharomyces cerevisiae.

Molecular and Cellular Biology ◽

10.1128/mcb.9.9.4064 ◽

1989 ◽

Vol 9 (9) ◽

pp. 4064-4068 ◽

Cited By ~ 21

Author(s):

C Wittenberg ◽

S I Reed

Keyword(s):

Saccharomyces Cerevisiae ◽

Protein Kinase ◽

Yeast Strain ◽

Cell Cycle Progression ◽

G1 Arrest ◽

Yeast Saccharomyces Cerevisiae ◽

Environmental Signals ◽

Transgenic Yeast ◽

M Phase

Whereas the Cdc28 protein kinase of the budding yeast Saccharomyces cerevisiae plays an essential role in cell cycle progression during the G1 interval, a function in the progression from the G2 interval into M phase has been inferred for its homologs, including the Cdc2Hs protein kinase of humans. To better understand these apparently disparate roles, we constructed a yeast strain in which the resident CDC28 gene was replaced by its human homolog, CDC2Hs. This transgenic yeast strain was able to perform the G1 functions attributed to the Cdc28 protein kinase, including the ability to grow and divide normally, to respond to environmental signals that induce G1 arrest, and to regulate the Cdc2Hs protein kinase appropriately in response to these signals.

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Molecular analysis of SSN6, a gene functionally related to the SNF1 protein kinase of Saccharomyces cerevisiae.

Molecular and Cellular Biology ◽

10.1128/mcb.7.10.3637 ◽

1987 ◽

Vol 7 (10) ◽

pp. 3637-3645 ◽

Cited By ~ 95

Author(s):

J Schultz ◽

M Carlson

Keyword(s):

Saccharomyces Cerevisiae ◽

Protein Kinase ◽

Nucleotide Sequence ◽

Temperature Sensitive ◽

Missense Mutations ◽

Kinase Gene ◽

Multiple Copies ◽

Protein Kinase Gene ◽

Rna Disruption ◽

High Level

Mutations in the SSN6 gene suppress the invertase derepression defect caused by a lesion in the SNF1 protein kinase gene. We cloned the SSN6 gene of Saccharomyces cerevisiae and identified its 3.3-kilobase poly(A)-containing RNA. Disruption of the gene caused phenotypes similar to, but more severe than, those caused by missense mutations: high-level constitutivity for invertase, clumpiness, temperature-sensitive growth, alpha-specific mating defects, and failure to homozygous diploids to sporulate. In contrast, the presence of multiple copies of SSN6 interfered with derepression of invertase. An ssn6 mutation was also shown to cause glucose-insensitive expression of a GAL10-lacZ fusion and maltase. The mating defects of MAT alpha ssn6 strains were associated with production of two a-specific products, a-factor and barrier, and reduced levels of alpha-factor; no deficiency of MAT alpha 2 RNA was detected. We showed that ssn6 partially restored invertase expression in a cyr1-2 mutant, although ssn6 was clearly not epistatic to cyr1-2. We also determined the nucleotide sequence of SSN6, which is predicted to encode a 107-kilodalton protein with stretches of polyglutamine and poly(glutamine-alanine). Possible functions of the SSN6 product are discussed.

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Identification of Genes That Function in the Biogenesis and Localization of Small Nucleolar RNAs in Saccharomyces cerevisiae

Molecular and Cellular Biology ◽

10.1128/mcb.01115-07 ◽

2008 ◽

Vol 28 (11) ◽

pp. 3686-3699 ◽

Cited By ~ 13

Author(s):

Hui Qiu ◽

Julia Eifert ◽

Ludivine Wacheul ◽

Marc Thiry ◽

Adam C. Berger ◽

...

Keyword(s):

Saccharomyces Cerevisiae ◽

Ribosome Biogenesis ◽

Large Scale ◽

Cajal Body ◽

Temperature Sensitive ◽

Small Nucleolar Rnas ◽

Animal Cells ◽

U3 Snorna ◽

Genes Encoding ◽

Nucleolar Rnas

ABSTRACT Small nucleolar RNAs (snoRNAs) orchestrate the modification and cleavage of pre-rRNA and are essential for ribosome biogenesis. Recent data suggest that after nucleoplasmic synthesis, snoRNAs transiently localize to the Cajal body (in plant and animal cells) or the homologous nucleolar body (in budding yeast) for maturation and assembly into snoRNPs prior to accumulation in their primary functional site, the nucleolus. However, little is known about the trans-acting factors important for the intranuclear trafficking and nucleolar localization of snoRNAs. Here, we describe a large-scale genetic screen to identify proteins important for snoRNA transport in Saccharomyces cerevisiae. We performed fluorescence in situ hybridization analysis to visualize U3 snoRNA localization in a collection of temperature-sensitive yeast mutants. We have identified Nop4, Prp21, Tao3, Sec14, and Htl1 as proteins important for the proper localization of U3 snoRNA. Mutations in genes encoding these proteins lead to specific defects in the targeting or retention of the snoRNA to either the nucleolar body or the nucleolus. Additional characterization of the mutants revealed impairment in specific steps of U3 snoRNA processing, demonstrating that snoRNA maturation and trafficking are linked processes.

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Alteration of the Protein Kinase Binding Domain Enhances Function of the Saccharomyces cerevisiae Molecular Chaperone Cdc37

Eukaryotic Cell ◽

10.1128/ec.00165-07 ◽

2007 ◽

Vol 6 (8) ◽

pp. 1363-1372 ◽

Cited By ~ 5

Author(s):

Min Ren ◽

Arti Santhanam ◽

Paul Lee ◽

Avrom Caplan ◽

Stephen Garrett

Keyword(s):

Saccharomyces Cerevisiae ◽

Protein Kinase ◽

Protein Kinases ◽

Molecular Chaperone ◽

Binding Domain ◽

Growth Defect ◽

Temperature Sensitive ◽

Physical Interaction ◽

General Function ◽

Amino Terminal

ABSTRACT Cdc37 is a molecular chaperone that has a general function in the biogenesis of protein kinases. We identified mutations within the putative “protein kinase binding domain” of Cdc37 that alleviate the conditional growth defect of a strain containing a temperature-sensitive allele, tpk2(Ts), of the cyclic AMP-dependent protein kinase (PKA). These dominant mutations alleviate the temperature-sensitive growth defect by elevating PKA activity, as judged by their effects on PKA-regulated processes, localization and phosphorylation of the PKA effector Msn2, as well as in vitro PKA activity. Although the tpk2(Ts) growth defect is also alleviated by Cdc37 overproduction, the CDC37 dominant mutants contain wild-type Cdc37 protein levels. In addition, Saccharomyces cerevisiae Ste11 protein kinase has an elevated physical interaction with the altered Cdc37 protein. These results implicate specific amino-terminal residues in the interaction between Cdc37 and client protein kinases and provide further genetic and biochemical support for a model in which Cdc37 functions as a molecular chaperone for protein kinases.

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Temperature-Sensitive Lethal Pseudorevertants of ste Mutations in Saccharomyces cerevisiae

Genetics ◽

10.1093/genetics/115.4.627 ◽

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.

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