Saccharomyces cerevisiae Afr1 Protein Is a Protein Phosphatase 1/Glc7-Targeting Subunit That Regulates the Septin Cytoskeleton during Mating

ABSTRACT Glc7, the type1 serine/threonine phosphatase in the yeast Saccharomyces cerevisiae, is targeted by auxiliary subunits to numerous locations in the cell, where it regulates a range of physiological pathways. We show here that the accumulation of Glc7 at mating projections requires Afr1, a protein required for the formation of normal projections. AFR1-null mutants fail to target Glc7 to projections, and an Afr1 variant specifically defective in binding to Glc7 [Afr1(V546A F548A)] forms aberrant projections. The septin filaments in mating projections of AFR1 mutants initiate normally but then rearrange asymmetrically as the projection develops, suggesting that the Afr1-Glc7 holoenzyme may regulate the maintenance of septin complexes during mating. These results demonstrate a previously unknown role for Afr1 in targeting Glc7 to mating projections and in regulating the septin architecture during mating.

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The Saccharomyces cerevisiae 14-3-3 protein Bmh2 is required for regulation of the phosphorylation status of Fin1, a novel intermediate filament protein

Biochemical Journal ◽

10.1042/bj20020053 ◽

2002 ◽

Vol 365 (1) ◽

pp. 51-56 ◽

Cited By ~ 14

Author(s):

Isabel MAYORDOMO ◽

Pascual SANZ

Keyword(s):

Saccharomyces Cerevisiae ◽

Transcriptional Regulation ◽

Intermediate Filament ◽

Protein Phosphatase ◽

Catalytic Subunit ◽

Protein Phosphatase 1 ◽

Intermediate Filament Protein ◽

Filament Protein ◽

Two Hybrid ◽

Hybrid Screening

In order to identify proteins that interact with Bmh2, a yeast member of the 14-3-3 protein family, we performed a two-hybrid screening using LexA-Bmh2 as bait. We identified Fin1, a novel intermediate filament protein, as the protein that showed the highest degree of interaction. We also identified components of the vesicular transport machinery such as Gic2 and Msb3, proteins involved in transcriptional regulation such as Mbf1, Gcr2 and Reg2, and a variety of other different proteins (Ppt1, Lre1, Rps0A and Ylr177w). We studied the interaction between Bmh2 and Fin1 in more detail and found that Bmh2 only interacted with phosphorylated forms of Fin1. In addition, we showed that Glc7, the catalytic subunit of the protein phosphatase 1 complex, was also able to interact with Fin1.

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Sds22p Is a Subunit of a Stable Isolatable Form of Protein Phosphatase 1 (Glc7p) from Saccharomyces cerevisiae

Archives of Biochemistry and Biophysics ◽

10.1006/abbi.2000.1715 ◽

2000 ◽

Vol 376 (2) ◽

pp. 288-298 ◽

Cited By ~ 14

Author(s):

Guang Hong ◽

Robert J. Trumbly ◽

Erwin M. Reimann ◽

Keith K. Schlender

Keyword(s):

Saccharomyces Cerevisiae ◽

Protein Phosphatase ◽

Protein Phosphatase 1 ◽

A Subunit

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Glucose-regulated interaction of a regulatory subunit of protein phosphatase 1 with the Snf1 protein kinase in Saccharomyces cerevisiae

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.95.11.6245 ◽

1998 ◽

Vol 95 (11) ◽

pp. 6245-6250 ◽

Cited By ~ 130

Author(s):

K. Ludin ◽

R. Jiang ◽

M. Carlson

Keyword(s):

Saccharomyces Cerevisiae ◽

Protein Kinase ◽

Protein Phosphatase ◽

Protein Phosphatase 1 ◽

Regulatory Subunit

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Protein Phosphatase 1 in association with Bud14 inhibits mitotic exit in Saccharomyces cerevisiae

10.1101/2020.08.30.273946 ◽

2020 ◽

Author(s):

Dilara Kocakaplan ◽

Hüseyin Karabürk ◽

Cansu Dilege ◽

Idil Kirdok ◽

Şeyma Nur Erkan ◽

...

Keyword(s):

Saccharomyces Cerevisiae ◽

Mitotic Spindle ◽

Protein Phosphatase ◽

Budding Yeast ◽

Mitotic Exit ◽

Protein Phosphatase 1 ◽

Inhibitory Function ◽

Surveillance Mechanism ◽

Spindle Position

AbstractSaccharomyces cerevisiae, also known as the budding yeast, orients and elongates its mitotic spindle along its polarity axis in order to segregate one copy of its genomic DNA to the daughter cell. When accurate positioning of the mitotic spindle fails, a surveillance mechanism, named the Spindle Position Checkpoint (SPOC), prevents cells from exiting mitosis unless the spindle orientation is corrected. Mutants with a defective SPOC loss their genomic integrity, become multiploid and aneuploid. Thus, SPOC is a crucial checkpoint for the budding yeast. Yet, a comprehensive understanding of how the SPOC mechanism works is missing. In this study, we identified Bud14 as a novel checkpoint protein. We showed that the mitotic exit inhibitory function of Bud14 requires its association with the type 1 protein phosphatase, Glc7. Our data indicate that Glc7-Bud14 promotes dephosphorylation of the SPOC effector protein Bfa1. Our results support a model in which Glc7-Bud14 works parallel to the SPOC kinase Kin4 in inhibiting mitotic exit.

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