Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

The CDK Pho85 inhibits Whi7 Start repressor to promote cell cycle entry in budding yeast

ABSTRACT: Pho85 is a multifunctional CDK that signals to the cell when environmental conditions are favorable. It has been connected to cell cycle control, mainly in Start where it promotes the G1/S transition. Here we describe that the Start repressor Whi7 is a key target of Pho85 in the regulation of cell cycle entry. The phosphorylation of Whi7 by Pho85 inhibits the repressor and explains most of the contribution of the CDK in the activation of Start. Mechanistically, Pho85 down-regulates Whi7 protein levels through the control Whi7 protein stability and WHI7 gene transcription. Whi7 phosphorylation by Pho85 also restrains the intrinsic ability of Whi7 to associate with promoters. Furthermore, although Whi5 is the main Start repressor in normal cycling cells, in the absence of Pho85 Whi7 becomes the major repressor leading to G1 arrest. Overall, our results reveal a novel mechanism by which Pho85 promotes Start through the regulation of the Whi7 repressor at multiple levels, which may confer to Whi7 a functional specialization to connect the response to adverse conditions with the cell cycle control.

INSTRUMENT(S): Bruker Daltonics instrument model

ORGANISM(S): Saccharomyces Cerevisiae (baker's Yeast) Saccharomyces Cerevisiae

SUBMITTER: Luz Valero

LAB HEAD: Juan Carlos Igual

PROVIDER: PXD046448 | Pride | 2023-12-13

REPOSITORIES: Pride

ACCESS DATA

Json Xml

Similar Datasets

Differential scaling between G1 protein production and cell size dynamics promotes commitment to the cell division cycle in budding yeast

Project description:In the unicellular eukaryote Saccharomyces cerevisiae, Cln3-CDK activity enables Start, the irreversible commitment to the cell division cycle. However, the concentration of Cln3 has been paradoxically considered to remain constant during G1, due to the presumed scaling of its production rate with cell size dynamics. Measuring metabolic and biosynthetic activity during cell cycle progression in single cells, we found that cells exhibit pulses in protein production rate, which do not scale with cell size dynamics, but -following the intrinsic metabolic dynamics- peak around Start. Using a viral-based bicistronic construct and targeted proteomics to measure Cln3 at the single-cell and population level, we show that the differential scaling between protein production and cell size leads to a temporal increase in Cln3 concentration, and passage through Start. This differential scaling causes Start in both daughter and mother cells, across growth conditions. Thus, uncoupling between two fundamental physiological parameters drives cell cycle commitment.

2019-10-29 | PXD015327 | Pride

Ubiquitin-specific proximity labeling for the identification of E3 ubiquitin ligase substrates

Project description:Protein ubiquitination controls diverse processes within eukaryotic cells, including protein degradation, and is often dysregulated in diseases1. Moreover, protein degraders that redirect ubiquitination activities toward disease targets are an emerging and promising therapeutic class2. Over 600 E3 ubiquitin ligases are expressed in humans3,4, but their substrates remain largely elusive due to a lack of robust methods to identify E3 ligase substrates. Here we report the development of E-STUB (E3 substrate tagging by ubiquitin biotinylation), a ubiquitin-specific proximity labeling method that biotinylates ubiquitinated substrates in proximity to an E3 ligase of interest. E-STUB accurately identifies the direct ubiquitinated targets of protein degraders, including collateral targets and ubiquitylation events that do not exhibit a degradative outcome. It also detects known substrates of E3 ligase cereblon (CRBN) and von Hippel-Lindau (VHL) with high precision. With the ability to elucidate proximal ubiquitination events, E-STUB may facilitate the development of proximity-inducing drugs and act as a generalizable method for E3 substrate mapping.

2024-03-20 | PXD042702 | Pride

Ubiquitin-specific proximity labeling for the identification of E3 ubiquitin ligase substrates

2024-03-20 | PXD042700 | Pride

Ubiquitin-specific proximity labeling for the identification of E3 ubiquitin ligase substrates

2024-03-20 | PXD042698 | Pride

Endometrial gland impacts on stromal cell decidualization

Project description:Uterine glands and, by inference, their secretions impact uterine receptivity, blastocyst implantation, stromal cell decidualization, and placental development. Changes in gland function across the menstrual cycle are impacted by steroid hormones, estrogen and progesterone, as well as stroma-derived factors. Using an endometrial epithelial organoid (EEO) system, transcriptome and proteome analyses identified distinct responses of the EEO to steroid hormones and prostaglandin E2 (PGE2). Notably, steroid hormones and PGE2 modulated the basolateral secretion of EEO proteins, where cystatin C (CST3) was significantly increased by progesterone and PGE2. CST3 treatment of decidualizing stromal cells significantly decreased the decidualization markers PRL and IGFBP1. The attenuation of stromal cell decidualization via CST3 suggests a role for uterine gland-derived proteins in controlling the extent of decidualization. These findings provide evidence that uterine gland-derived factors directly impact stromal cell decidualization, which has strong implications for better understanding pregnancy establishment and female fertility in humans.

2023-10-11 | PXD034357 | Pride

Budding yeast relies on qualitative G1 cyclin specificity to couple cell cycle progression with morphogenetic development

Project description:Two models have been put forward for cyclin-dependent kinase (Cdk) control of the cell cycle. In the qualitative model, cell cycle events are ordered by distinct substrate specificities associated with successive waves of G1, S and mitotic cyclins. Alternatively, the gradual quantitative rise of Cdk activity from G1 phase to mitosis could lead to ordered substrate phosphorylation at sequential thresholds. Here, we study the relative contributions of qualitative and quantitative Cdk control in the budding yeast S. cerevisiae. S-phase cyclins can be replaced by a single mitotic cyclin, albeit at the cost of reduced fitness. The single cyclin can in addition replace G1 cyclins to support ordered cell cycle progression, fulfilling key predictions of the quantitative model. However, single-cyclin cells fail to polarize or grow buds and thus cannot sustain proliferation. Our results suggest that budding yeast has become dependent on G1 cyclin specificity to couple cell cycle progression to essential morphogenetic events.

2021-08-23 | PXD022757 | Pride

Small Extracellular Vesicles from Hypoxic Triple-Negative Breast Cancer Cells induce Oxygen-dependent Cell Invasion

Project description:Hypoxia, a condition of low oxygenation frequently found in triple-negative breast tumors, is often related to increased extracellular vesicle (EV) secretion and favors cell invasion, which is a crucial step for metastasis. Cell invasion is a complex process in which cell morphology is altered due to F-actin cytoskeleton polarization and the establishment of dynamic focal adhesion spots, which coupled with ECM remodeling enables cells to migrate through tissues seeking a new developmental niche. In our in-depth investigation over the invasive properties triggered by TNBC-derived hypoxic small EVs (SEVh) in vitro, we analyzed the morphological, phenotypical and proteomic distinctions promoted by hypoxia and/or SEVh signaling in TNBC cells. SEVh was fully characterized and showed a distinct proteome and abundance profile from its normoxic counterparts. SEVh promotes invasive behaviors exclusively in normoxia, including pro-migratory morphology, invadopodia development, ECM degradation and gelatinase secretion, which indicates the importance of SEVh response on hypoxic settings in tumor progression. In hypoxia, SEVh was responsible for proteolytic and catabolic pathway inducement, interfering with integrin availability and gelatinase expression. Protein profiling of SEVh-treated, normoxic cells indicate a baseline favoring of metabolic processes and cell cycle, modulating cell health away from apoptotic pathways that are enriched in hypoxia. Overall, our results demonstrate the importance of hypoxic signaling via SEV in a tumoral setting for the early establishment of metastasis.

2022-11-01 | PXD035244 | Pride

The effect of multiple phaJ deletions Pseudomonas putida KT2440 on polyhydroxyalkanoates synthesis (part2)

Project description:Pseudomonas putida KT2440 is a well-known model organism for the medium chain length (mcl) PHA accumulation. (R)-Specific enoyl-coenzyme A hydratase (PhaJ) was considered to be the main supplier of monomers for PHA synthesis by converting the -oxidation intermediate, trans-2-enoyl-CoA to (R)-3-hydroxyacyl-CoA when fatty acids (FA) are used. Three PhaJ homologues, PhaJ1, PhaJ4 and MaoC are annotated in P. putida KT2440. To investigate the relationship of fatty acids - PHA metabolism and the role of each PhaJ in PHA biosynthesis in P. putida KT2440, a series of P. putida KT2440 knockouts was obtained. PHA content and monomer composition in WT and mutants under different growth conditions were analysed. However, when all three PhaJ homologues were deleted, the mutant still accumulated PHA up to 10.7 % of the cell dry weight (CDW). To identify other potential PHA monomer suppliers by analysing the proteome of the phaJ1maoCphaJ4. The deletion of (R)-3-hydroxydecanoyl-ACP:CoA transacylase (PhaG), which connects de novo FA and PHA synthesis pathways, while causing further 1.8-fold decrease in PHA content, did not abolish PHA accumulation. Further proteome analysis revealed quinoprotein alcohol dehydrogeanses PedE and PedH as potential monomer suppliers, but when these were deleted PHA level remained at 2.2 – 14.8 % CDW depending on the fatty acid used, and whether nitrogen limitation was applied. To identify the other non-specific dehydrogenases supply monomers for PHA synthesis, we analysed the proteome of the sextuple mutant under nitrogen limiting and non-limiting conditions.

2023-05-10 | PXD037937 | Pride

Sildenafil Combined with Controlled Hypothermia Mitigates Microglial Activation After Neonatal Hypoxia-Ischemia in Rat.

Project description:The only validated treatment to prevent brain damage associated with hypoxia-ischemia (HI) encephalopathy of the newborn is controlled hypothermia with limited benefits. Additional putative neuroprotective drug candidates include sildenafil citrate, a phosphodiesterase-type 5 inhibitor. The main objective of this preclinical study is to assess its ability to reduce HI-induced neuroinflammation, in particular through its potential effect on microglial activation. HI was induced in P10 Sprague–Dawley rats by unilateral carotid permanent artery occlusion and hypoxia (HI), and treated by either hypothermia (HT) alone, Sildenafil (Sild) alone or combined treatment (SildHT). Lesion size, glial activation were analyzed by immunohistochemistry, qRT-PCR and proteomic analyses performed at P13. Exposure to any treatment was not associated with significant reduction in lesions size both in cerebral cortex and hippocampus, 72h after HI. Significant reductions in either Iba1+ (within the ipsilateral hemisphere) or GFAP+ cells (within the ipsilateral hippocampus) were observed in SildHT group, but not in the other treatment groups. In microglia sorted cells, pro-inflammatory markers, ie. Il1b, Il6, Nos2, and CD86 were significantly downregulated in SildHT treatment group only. These changes were restricted to ipsilateral hemisphere, were not evidenced in sorted astrocytes, and were not sex-dependent. Proteomic analyses in sorted microglia refined the pro-inflammatory effect of HI and confirmed a biologically relevant impact of SildHT on specific molecular pathways including notably genes related to neutrophilic functions. Our findings demonstrate that Sildenafil combined with controlled hypothermia confers maximum effect to mitigate microglial activation induced by HI through complex proteomic regulation. The reduction of neuroinflammation induced by Sildenafil may represent an interesting therapeutic strategy for neonatal neuroprotection.

2024-04-30 | PXD045168 | Pride

The Centriolar Satellite Component CEP131 timely regulates mitochondrial Apoptosis

Project description:Centriolar satellites are multiprotein aggregates that orbit the centrosome and govern centrosome homeostasis and primary cilia formation. In contrast to the scaffold PCM1, which nucleates centriolar satellites and has been linked to microtubule dynamics, autophagy, and intracellular trafficking, the functions of its close interactant CEP131 beyond ciliogenesis remain unclear. By using a knockout strategy in a T-cell line unable to form primary cilia, we report that, although dispensable for centriolar satellite assembly, CEP131 participates in optimal tubulin modifications and microtubule regrowth. Our unsupervised label-free proteomic analysis by quantitative mass spectrometry further uncovered both a mitochondrial and an anti-apoptotic signature. Without CEP131, mitochondria showed increased respiration and formed a more elongated network. In response to cell death inducers converging on mitochondria, knockout cells displayed delayed cytochrome c release from mitochondria, subsequent caspases activation, and ultimately in apoptosis. This defect in mitochondrial permeabilization was intrinsic as it could be recapitulated in vitro with isolated organelles. Together, these data extend the functions of CEP131 to life-and-death decisions and propose ways to interfere with mitochondrial apoptosis.

2024-01-26 | PXD042470 | Pride

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data