Inducible degradation-coupled phosphoproteomics identifies PP2A-Rts1 as a novel eisosome regulator
Ontology highlight
ABSTRACT:
INSTRUMENT(S): Orbitrap Exploris 480, Q Exactive HF
ORGANISM(S): Saccharomyces Cerevisiae (baker's Yeast)
SUBMITTER: 
Mark Hall
LAB HEAD: Mark Hall
PROVIDER: PXD044337 | Pride | 2023-10-24
REPOSITORIES: Pride
Dataset's files
| Action | DRS | |||
|---|---|---|---|---|
| Cdc55-T1-F1_1_A.raw | Raw | |||
| Cdc55-T1-F2_1_A.raw | Raw | |||
| Cdc55-T1-F3_1_A.raw | Raw | |||
| Cdc55-T1-F4_1_A.raw | Raw | |||
| Cdc55-T1-F5_1_A.raw | Raw |
Items per page: 5 1 - 5 of 88 |
Similar Datasets
Project description:IntroductionReversible protein phosphorylation is an abundant post-translational modification dynamically regulated by opposing kinases and phosphatases. Protein phosphorylation has been extensively studied in cell division, where waves of cyclin-dependent kinase activity, peaking in mitosis, drive the sequential stages of the cell cycle. Here we developed and employed a strategy to specifically probe kinase or phosphatase substrates at desired times or experimental conditions in the model organism Saccharomyces cerevisiae.MethodsWe combined auxin-inducible degradation (AID) with mass spectrometry-based phosphoproteomics, which allowed us to arrest physiologically normal cultures in mitosis prior to rapid phosphatase degradation and phosphoproteome analysis.Results and discussionOur results revealed that protein phosphatase 2A coupled with its B56 regulatory subunit, Rts1 (PP2ARts1), is involved in dephosphorylation of numerous proteins in mitosis, highlighting the need for phosphatases to selectively maintain certain proteins in a hypophosphorylated state in the face of high mitotic kinase activity. Unexpectedly, we observed elevated phosphorylation at many sites on several subunits of the fungal eisosome complex following rapid Rts1 degradation. Eisosomes are dynamic polymeric assemblies that create furrows in the plasma membrane important in regulating nutrient import, lipid metabolism, and stress responses, among other things. We found that PP2ARts1-mediated dephosphorylation of eisosomes promotes their plasma membrane association and we provide evidence that this regulation impacts eisosome roles in metabolic homeostasis. The combination of rapid, inducible protein degradation with proteomic profiling offers several advantages over common protein disruption methods for characterizing substrates of regulatory enzymes involved in dynamic biological processes.
| S-EPMC11371571 | biostudies-literature
Project description:In animals, mitosis involves the breakdown of the nucleus. The reassembly of a nucleus after mitosis requires the reformation of the nuclear envelope around a single mass of chromosomes. This process requires Ankle2 (also known as LEM4 in humans) which interacts with PP2A and promotes the function of Barrier-to-Autointegration Factor (BAF). Upon dephosphorylation, BAF dimers cross-bridge chromosomes and bind lamins and transmembrane proteins of the reassembling nuclear envelope. How Ankle2 functions in mitosis is incompletely understood. Using a combination of approaches in Drosophila, along with structural modeling, we provide several lines of evidence that suggest that Ankle2 is a regulatory subunit of PP2A, explaining how it promotes BAF dephosphorylation. In addition, we discovered that Ankle2 interacts with the endoplasmic reticulum protein Vap33, which is required for Ankle2 localization at the reassembling nuclear envelope during telophase. We identified the interaction sites of PP2A and Vap33 on Ankle2. Through genetic rescue experiments, we show that the Ankle2/PP2A interaction is essential for the function of Ankle2 in nuclear reassembly and that the Ankle2/Vap33 interaction also promotes this process. Our study sheds light on the molecular mechanisms of post-mitotic nuclear reassembly and suggests that the endoplasmic reticulum is not merely a source of membranes in the process, but also provides localized enzymatic activity.
2025-01-31 | PXD059738 | Pride
Project description:The phosphorylation and dephosphorylation of transcription machinery are essential for the precise control of gene expression. A non-canonical protein phosphatase 2A (PP2A) holoenzyme (denoted INTAC), in which the 14-subunit Integrator recruits RNA polymerase II (Pol II) and the PP2A core enzyme dephosphorylates the C-terminal repeat domain (CTD) of Pol II at Serine-5 and Serine-2.
2020-12-02 | GSE154093 | GEO
Project description:During mitosis, TATA-binding protein(TBP), which remains bound to DNA during mitosis, recruits PP2A and also interacts with a subunit of the condensin complex to allow efficient dephosphorylation and inactivation of condensin near these promoters to inhibit their compaction. These result suggest that TBP function is not only important for expression of genes transcribed bDuring mitosis, TATA-binding protein(TBP), which remains bound to DNA during mitosis, recruits PP2A and also interacts with a subunit of the condensin complex to allow efficient dephosphorylation and inactivation of condensin near these promoters to inhibit their compaction. These result suggest that TBP function is not only important for expression of genes transcribed by all three RNA polymerase during interphase, but also for transmitting the memory of gene activity through mitosis to daughter cellsy all three RNA polymerase during interphase, but also for transmitting the memory of gene activity through mitosis to daughter cells
2009-05-28 | GSE12256 | GEO
Project description:During mitosis, TATA-binding protein(TBP), which remains bound to DNA during mitosis, recruits PP2A and also interacts with a subunit of the condensin complex to allow efficient dephosphorylation and inactivation of condensin near these promoters to inhibit their compaction. These result suggest that TBP function is not only important for expression of genes transcribed bDuring mitosis, TATA-binding protein(TBP), which remains bound to DNA during mitosis, recruits PP2A and also interacts with a subunit of the condensin complex to allow efficient dephosphorylation and inactivation of condensin near these promoters to inhibit their compaction. These result suggest that TBP function is not only important for expression of genes transcribed by all three RNA polymerase during interphase, but also for transmitting the memory of gene activity through mitosis to daughter cellsy all three RNA polymerase during interphase, but also for transmitting the memory of gene activity through mitosis to daughter cells We use ChIP-chip approach to identify TBP-bindind sites in mitotic Jurkat cells at genome-wide level. Input DNA fragments and DNA fragments immunoprecipitated by TBP antibodies by ChIP assay on mitotic Jurkat cells were used to probe the Affymetrix Genechip human tiling 2.0c to identift TBP-binding sites in mitotic Jurkat cells. Input and ChIP sample were replicated three times as following: Input rep1, TBP ChIP1, Input rep2, TBP ChIP2, Input rep3, TBP ChIP3.
2010-04-03 | E-GEOD-12256 | biostudies-arrayexpress
Project description:Entry into mitosis is triggered by mitotic kinases that phosphorylate multiple proteins to induce profound cellular changes including nuclear envelope breakdown, chromosome condensation and spindle assembly. Conversely, mitotic exit requires protein dephosphorylation as cells return to their interphase organization. Protein Phosphatase 2A in complex with its B55/Tws regulatory subunit (PP2A-B55) is known to play a crucial role in this transition. However, the precise events and substrates that it regulates are incompletely understood. We used proteomic approaches in Drosophila to identify proteins that interact with PP2A-B55 and are dephosphorylated in a PP2A-B55 dependent manner. Among several candidates, we identified Otefin (also known as Emerin) as a target of PP2A-B55 in the process of nuclear envelope reformation after mitosis. Emerin is a protein of the inner nuclear membrane that interacts with the DNA-binding protein Barrier-to-Autointegration Factor (BAF) via a LEM domain. Our results indicate that phosphorylation of Emerin at Ser50 and Ser54 near its LEM domain negatively regulates its association with BAF, Lamin and additional Emerin. Using live imaging, we show that dephosphorylation of Emerin at the identified sites determines the timing of nuclear envelope reformation. Genetic rescue experiments indicate that this regulation is required in vivo during embryonic development. Phosphoregulation of the Emerin-BAF complex formation by PP2A-B55 appears as a key event of mitotic exit that is likely to be conserved across species.
2023-08-10 | PXD041030 | Pride
Project description:Entry into mitosis is triggered by mitotic kinases that phosphorylate multiple proteins to induce profound cellular changes including nuclear envelope breakdown, chromosome condensation and spindle assembly. Conversely, mitotic exit requires protein dephosphorylation as cells return to their interphase organization. Protein Phosphatase 2A in complex with its B55/Tws regulatory subunit (PP2A-B55) is known to play a crucial role in this transition. However, the precise events and substrates that it regulates are incompletely understood. We used proteomic approaches in Drosophila to identify proteins that interact with PP2A-B55 and are dephosphorylated in a PP2A-B55 dependent manner. Among several candidates, we identified Otefin (also known as Emerin) as a target of PP2A-B55 in the process of nuclear envelope reformation after mitosis. Emerin is a protein of the inner nuclear membrane that interacts with the DNA-binding protein Barrier-to-Autointegration Factor (BAF) via a LEM domain. Our results indicate that phosphorylation of Emerin at Ser50 and Ser54 near its LEM domain negatively regulates its association with BAF, Lamin and additional Emerin. Using live imaging, we show that dephosphorylation of Emerin at the identified sites determines the timing of nuclear envelope reformation. Genetic rescue experiments indicate that this regulation is required in vivo during embryonic development. Phosphoregulation of the Emerin-BAF complex formation by PP2A-B55 appears as a key event of mitotic exit that is likely to be conserved across species.
2023-08-10 | PXD041091 | Pride
Project description:Entry into mitosis is triggered by mitotic kinases that phosphorylate multiple proteins to induce profound cellular changes including nuclear envelope breakdown, chromosome condensation and spindle assembly. Conversely, mitotic exit requires protein dephosphorylation as cells return to their interphase organization. Protein Phosphatase 2A in complex with its B55/Tws regulatory subunit (PP2A-B55) is known to play a crucial role in this transition. However, the precise events and substrates that it regulates are incompletely understood. We used proteomic approaches in Drosophila to identify proteins that interact with PP2A-B55 and are dephosphorylated in a PP2A-B55 dependent manner. Among several candidates, we identified Otefin (also known as Emerin) as a target of PP2A-B55 in the process of nuclear envelope reformation after mitosis. Emerin is a protein of the inner nuclear membrane that interacts with the DNA-binding protein Barrier-to-Autointegration Factor (BAF) via a LEM domain. Our results indicate that phosphorylation of Emerin at Ser50 and Ser54 near its LEM domain negatively regulates its association with BAF, Lamin and additional Emerin. Using live imaging, we show that dephosphorylation of Emerin at the identified sites determines the timing of nuclear envelope reformation. Genetic rescue experiments indicate that this regulation is required in vivo during embryonic development. Phosphoregulation of the Emerin-BAF complex formation by PP2A-B55 appears as a key event of mitotic exit that is likely to be conserved across species.
2023-08-10 | PXD041032 | Pride
Project description:Temporal control over protein phosphorylation and dephosphorylation is crucial for accurate chromosome segregation and for completion of the cell division cycle during exit from mitosis. In budding yeast, the Cdc14 phosphatase is thought to be a major regulator at this time, while in higher eukaryotes PP2A phosphatases take a dominant role. Here, we use time-resolved phosphoproteome analysis in budding yeast to evaluate the respective contributions of Cdc14 and the two main PP2A isoforms, PP2A(Cdc55) and PP2A(Rts1). This reveals an overlapping requirement for all three phosphatases during mitotic progression. Cdc14 instructs the sequential pattern of phosphorylation changes, in part through its preferential recognition of serine-based cyclin-dependent kinase (Cdk) substrates. PP2A(Cdc55) and PP2A(Rts1) in turn exhibit a broad substrate spectrum with some selectivity for phospho-threonines and a role for PP2A(Rts1) in sustaining Aurora kinase activity. Our results illustrate synergy and coordination between phosphatases as they orchestrate phosphoproteome dynamics during mitotic progression.
2019-11-12 | PXD012860 | Pride
Project description:Mutations in leucine rich repeat kinase 2 (LRRK2) are a common cause of inherited and sporadic Parkinson’s disease (PD) and previous work suggests that dephosphorylation of LRRK2 at a cluster of heterologous phosphosites is associated to disease. We have previously reported subunits of the PP1 and PP2A classes of phosphatases as well as the PAK6 kinase as regulators of LRRK2 dephosphorylation. We therefore hypothesized that PAK6 may have a functional link with LRRK2’s phosphatases. To investigate this, we used PhosTag with purified proteins and found that PAK6 phosphorylates the PP2A regulatory subunit PPP2R2C at position S381. While S381 phosphorylation did not affect PP2A holoenzyme formation, a S381A phosphodead PPP2R2C showed impaired binding to LRRK2. Also, PAK6 kinase activity changed PPP2R2C subcellular localization in a S381 phosphorylation-dependent manner. Finally, PAK6-mediated dephosphorylation of LRRK2 was unaffected by phosphorylation of PPP2R2C at S381, suggesting that this mechanism is likely subordinate to the previously reported mechanism whereby PAK6-mediated phosphorylation of 14-3-3 proteins promotes 14-3-3-LRRK2 complex dissociation and consequent exposure of LRRK2 phosphosites for dephosphorylation. Taken together, we conclude that PAK6-mediated phosphorylation of PPP2R2C regulates recruitment of PPP2R2C to the LRRK2 complex and PPP2R2C subcellular localization, pointing to an additional mechanism in the fine-tuning of LRRK2 phosphoregulation.
2023-12-06 | PXD044933 | Pride