An ?-specific gene, SAG1 is required for sexual agglutination in Saccharomyces cerevisiae

1989 ◽  
Vol 15 (6) ◽  
pp. 393-398 ◽  
Author(s):  
Syuichi Doi ◽  
Kazuyuki Tanabe ◽  
Masayasu Watanabe ◽  
Masayoshi Yamaguchi ◽  
Masao Yoshimura
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Specific Gene ◽  
Sexual Agglutination

scholarly journals Transcription of alpha-specific genes in Saccharomyces cerevisiae: DNA sequence requirements for activity of the coregulator alpha 1.

1993 ◽  
Vol 13 (11) ◽  
pp. 6866-6875 ◽  
Author(s):  
D C Hagen ◽  
L Bruhn ◽  
C A Westby ◽  
G F Sprague
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Binding Site ◽  
Dna Sequences ◽  
Point Mutations ◽  
Transcription Activation ◽  
Specific Gene ◽  
Binding Assays ◽  
Weak Binding

Transcription activation of alpha-specific genes in Saccharomyces cerevisiae is regulated by two proteins, MCM1 and alpha 1, which bind to DNA sequences, called P'Q elements, found upstream of alpha-specific genes. Neither MCM1 nor alpha 1 alone binds efficiently to P'Q elements. Together, however, they bind cooperatively in a manner that requires both the P' sequence, which is a weak binding site for MCM1, and the Q sequence, which has been postulated to be the binding site for alpha 1. We analyzed a collection of point mutations in the P'Q element of the STE3 gene to determine the importance of individual base pairs for alpha-specific gene transcription. Within the 10-bp conserved Q sequence, mutations at only three positions strongly affected transcription activation in vivo. These same mutations did not affect the weak binding to P'Q displayed by MCM1 alone. In vitro DNA binding assays showed a direct correlation between the ability of the mutant sequences to form ternary P'Q-MCM1-alpha 1 complexes and the degree to which transcription was activated in vivo. Thus, the ability of alpha 1 and MCM1 to bind cooperatively to P'Q elements is critical for activation of alpha-specific genes. In all natural alpha-specific genes the Q sequence is adjacent to the degenerate side of P'. To test the significance of this geometry, we created several novel juxtapositions of P, P', and Q sequences. When the Q sequence was opposite the degenerate side, the composite QP' element was inactive as a promoter element in vivo and unable to form stable ternary QP'-MCM1-alpha 1 complexes in vitro. We also found that addition of a Q sequence to a strong MCM1 binding site allows the addition of alpha 1 to the complex. This finding, together with the observation that Q-element point mutations affected ternary complex formation but not the weak binding of MCM1 alone, supports the idea that the Q sequence serves as a binding site for alpha 1.

SPK1 is an essential S-phase-specific gene of Saccharomyces cerevisiae that encodes a nuclear serine/threonine/tyrosine kinase

1993 ◽  
Vol 13 (9) ◽  
pp. 5829-5842
Author(s):  
P Zheng ◽  
D S Fay ◽  
J Burton ◽  
H Xiao ◽  
J L Pinkham ◽  
...  
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Cell Cycle ◽  
Dna Damage ◽  
Dna Synthesis ◽  
Genomic Library ◽  
Excision Repair ◽  
Low Frequency ◽  
S Phase ◽  
Upstream Region ◽  
Specific Gene

SPK1 was originally discovered in an immunoscreen for tyrosine-protein kinases in Saccharomyces cerevisiae. We have used biochemical and genetic techniques to investigate the function of this gene and its encoded protein. Hybridization of an SPK1 probe to an ordered genomic library showed that SPK1 is adjacent to PEP4 (chromosome XVI L). Sporulation of spk1/+ heterozygotes gave rise to spk1 spores that grew into microcolonies but could not be further propagated. These colonies were greatly enriched for budded cells, especially those with large buds. Similarly, eviction of CEN plasmids bearing SPK1 from cells with a chromosomal SPK1 disruption yielded viable cells with only low frequency. Spk1 protein was identified by immunoprecipitation and immunoblotting. It was associated with protein-Ser, Thr, and Tyr kinase activity in immune complex kinase assays. Spk1 was localized to the nucleus by immunofluorescence. The nucleotide sequence of the SPK1 5' noncoding region revealed that SPK1 contains two MluI cell cycle box elements. These elements confer S-phase-specific transcription to many genes involved in DNA synthesis. Northern (RNA) blotting of synchronized cells verified that the SPK1 transcript is coregulated with other MluI box-regulated genes. The SPK1 upstream region also includes a domain highly homologous to sequences involved in induction of RAD2 and other excision repair genes by agents that induce DNA damage. spk1 strains were hypersensitive to UV irradiation. Taken together, these findings indicate that SPK1 is a dual-specificity (Ser/Thr and Tyr) protein kinase that is essential for viability. The cell cycle-dependent transcription, presence of DNA damage-related sequences, requirement for UV resistance, and nuclear localization of Spk1 all link this gene to a crucial S-phase-specific role, probably as a positive regulator of DNA synthesis.

scholarly journals Yeast repressor alpha 2 binds to its operator cooperatively with yeast protein Mcm1.

1989 ◽  
Vol 9 (11) ◽  
pp. 5228-5230 ◽  
Author(s):  
C A Keleher ◽  
S Passmore ◽  
A D Johnson
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Gene Product ◽  
Strong Evidence ◽  
Regulatory Proteins ◽  
Yeast Cells ◽  
Specific Gene ◽  
Yeast Gene ◽  
Yeast Protein ◽  
Transcriptional Regulatory

To bring about repression of a family fo genes in Saccharomyces cerevisiae called the a-specific genes, two transcriptional regulatory proteins, alpha 2 and GRM (general regulator of matin type), bind cooperatively to an operator found upstream of each a-specific gene. To date, GRM has been defined only biochemically. In this communication we show that the product of a single yeast gene (MCM1) is sufficient to bind cooperatively with alpha 2 to the operator. We also show that antiserum raised against the MCM1 gene product recognizes GRM from yeast cells. These results, in combination with previous observations, provide strong evidence that MCM1 encodes the GRM activity.

scholarly journals Identification of a DNA segment that is necessary and sufficient for alpha-specific gene control in Saccharomyces cerevisiae: implications for regulation of alpha-specific and a-specific genes.

1988 ◽  
Vol 8 (1) ◽  
pp. 309-320 ◽  
Author(s):  
E E Jarvis ◽  
D C Hagen ◽  
G F Sprague
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Binding Site ◽  
Transcript Level ◽  
Cell Types ◽  
Specific Gene ◽  
Alpha Cells ◽  
Transcription Activator ◽  
Noncoding Sequences ◽  
Necessary And Sufficient ◽  
Activation Sequence

STE3 mRNA is present only in Saccharomyces cerevisiae alpha cells, not in a or a/alpha cells, and the transcript level increases about fivefold when cells are treated with a-factor mating pheromone. Deletions in the 5' noncoding region of STE3 defined a 43-base-pair (bp) upstream activation sequence (UAS) that can impart both modes of regulation to a CYC1-lacZ fusion when substituted for the native CYC1 UAS. UAS activity required the alpha 1 product of MAT alpha, which is known to be required for transcription of alpha-specific genes. A chromosomal deletion that removed only 14 bp of the STE3 UAS reduced STE3 transcript levels 50- to 100-fold, indicating that the UAS is essential for expression. The STE3 UAS shares a 26-bp homology with the 5' noncoding sequences of the only other known alpha-specific genes, MF alpha 1 and MF alpha 2. We view the homology as having two components--a nearly palindromic 16-bp "P box" and an adjacent 10-bp "Q box." A synthetic STE3 P box was inactive as a UAS; a perfect palindrome P box was active in all three cell types. We propose that the P box is the binding site for a transcription activator, but that alpha 1 acting via the Q box is required for this activator to bind to the imperfect P boxes of alpha-specific genes. Versions of the P box are also found upstream of a-specific genes, within the binding sites of the repressor alpha 2 encoded by MAT alpha. Thus, the products of MAT alpha may render gene expression alpha or a-specific by controlling access of the same transcription activator to its binding site, the P box.

Sexual Agglutination in Saccharomyces cerevisiae

Botanica Acta ◽  
1995 ◽  
Vol 108 (2) ◽  
pp. 63-66 ◽  
Author(s):  
Karin Hauser ◽  
W. Tanner
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Sexual Agglutination

Positive control of sporulation-specific genes by the IME1 and IME2 products in Saccharomyces cerevisiae

1990 ◽  
Vol 10 (5) ◽  
pp. 2104-2110
Author(s):  
A P Mitchell ◽  
S E Driscoll ◽  
H E Smith
Keyword(s):  
Gene Expression ◽  
Saccharomyces Cerevisiae ◽  
Meiotic Recombination ◽  
Positive Control ◽  
Spore Formation ◽  
Specific Gene ◽  
Heterologous Promoter ◽  
Yeast Saccharomyces Cerevisiae ◽  
Specific Gene Expression ◽  
Rapid Induction

In the yeast Saccharomyces cerevisiae, meiosis and spore formation require the induction of sporulation-specific genes. Two genes are thought to activate the sporulation program: IME1 and IME2 (inducer of meiosis). Both genes are induced upon entry into meiosis, and IME1 is required for IME2 expression. We report here that IME1 is essential for expression of four sporulation-specific genes. In contrast, IME2 is not absolutely essential for expression of the sporulation-specific genes, but contributes to their rapid induction. Expression of IME2 from a heterologous promoter permits the expression of these sporulation-specific genes, meiotic recombination, and spore formation in the absence of IME1. We propose that the IME1 and IME2 products can each activate sporulation-specific genes independently. In addition, the IME1 product stimulates sporulation-specific gene expression indirectly through activation of IME2 expression.

Regulation of STA1 gene expression by MAT during the life cycle of Saccharomyces cerevisiae

1989 ◽  
Vol 9 (9) ◽  
pp. 3992-3998
Author(s):  
A M Dranginis
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Mating Type ◽  
Yeast Cells ◽  
Specific Gene ◽  
Activity Levels ◽  
Sporulation Medium ◽  
Mrna Levels ◽  
Yeast Saccharomyces Cerevisiae ◽  
Type Locus ◽  
Diploid Cells

STA1 encodes a secreted glucoamylase of the yeast Saccharomyces cerevisiae var. diastaticus. Glucoamylase secretion is controlled by the mating type locus MAT; a and alpha haploid yeast cells secrete high levels of the enzyme, but a/alpha diploid cells produce undetectable amounts. It has been suggested that STA1 is regulated by MATa2 (I. Yamashita, Y. Takano, and S. Fukui, J. Bacteriol. 164:769-773, 1985), which is a MAT transcript of previously unknown function. In contrast, this work shows that deletion of the entire MATa2 gene had no effect on STA1 regulation but that deletion of MATa1 sequences completely abolished mating-type control. In all cases, glucoamylase activity levels reflected STA1 mRNA levels. It appears that STA1 is a haploid-specific gene that is regulated by MATa1 and a product of the MAT alpha locus and that this regulation occurs at the level of RNA accumulation. STA1 expression was also shown to be glucose repressible. STA1 mRNA was induced in diploids during sporulation along with SGA, a closely linked gene that encodes an intracellular sporulation-specific glucoamylase of S. cerevisiae. A diploid strain with a MATa1 deletion showed normal induction of STA1 in sporulation medium, but SGA expression was abolished. Therefore, these two homologous and closely linked glucoamylase genes are induced by different mechanisms during sporulation. STA1 induction may be a response to the starvation conditions necessary for sporulation, while SGA induction is governed by the pathway by which MAT regulates sporulation. The strain containing a complete deletion of MATa2 grew, mated, and sporulated normally.

Identification of sequence elements that confer cell-type-specific control of MF alpha 1 expression in Saccharomyces cerevisiae

1987 ◽  
Vol 7 (9) ◽  
pp. 3185-3193
Author(s):  
K Inokuchi ◽  
A Nakayama ◽  
F Hishinuma
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Mating Type ◽  
Specific Gene ◽  
Cell Type ◽  
Coding Region ◽  
Transcription Start ◽  
Specific Expression ◽  
Type Locus ◽  
Mating Type Locus ◽  
Cell Type Specific

The MF alpha 1 gene of Saccharomyces cerevisiae, a major structural gene for mating pheromone alpha factor, is an alpha-specific gene whose expression is regulated by the mating-type locus. To study the role of sequences upstream of MF alpha 1 in its expression and regulation, we generated two sets of promoter deletions: upstream deletions and internal deletions. By analyzing these deletions, we have identified a TATA box and two closely related, tandemly arranged upstream activation sites as necessary elements for MF alpha 1 expression. Two upstream activation sites were located ca. 300 and 250 base pairs upstream of the MF alpha 1 transcription start points, which were also determined in this study. Each site contained a homologous 22-base-pair sequence, and both sites were required for maximum transcription level. The distance between the upstream activation sites and the transcription start points could be altered without causing loss of transcription efficiency, and the sites were active in either orientation with respect to the coding region. These elements conferred cell type-specific expression on a heterologous promoter. Analysis with host mating-type locus mutants indicates that these sequences are the sites through which the MAT alpha 1 product exerts its action to activate the MF alpha 1 gene. Homologous sequences with these elements were found in other alpha-specific genes, MF alpha 2 and STE3, and may mediate activation of this set of genes by MAT alpha 1.

Sign in / Sign up

Export Citation Format

Share Document