124 research outputs found

    Pheromone-induced polarization is dependent on the Fus3p MAPK acting through the formin Bni1p

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    During mating, budding yeast cells reorient growth toward the highest concentration of pheromone. Bni1p, a formin homologue, is required for this polarized growth by facilitating cortical actin cable assembly. Fus3p, a pheromone-activated MAP kinase, is required for pheromone signaling and cell fusion. We show that Fus3p phosphorylates Bni1p in vitro, and phosphorylation of Bni1p in vivo during the pheromone response is dependent on Fus3p. fus3 mutants exhibited multiple phenotypes similar to bni1 mutants, including defects in actin and cell polarization, as well as Kar9p and cytoplasmic microtubule localization. Disruption of the interaction between Fus3p and the receptor-associated Gα subunit caused similar mutant phenotypes. After pheromone treatment, Bni1p-GFP and Spa2p failed to localize to the cortex of fus3 mutants, and cell wall growth became completely unpolarized. Bni1p overexpression suppressed the actin assembly, cell polarization, and cell fusion defects. These data suggest a model wherein activated Fus3p is recruited back to the cortex, where it activates Bni1p to promote polarization and cell fusion.</jats:p

    Statin intensity and risk for cardiovascular events after heart transplantation

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    AimsStatins improve survival and reduce rejection and cardiac allograft vasculopathy after heart transplantation (HT). The impact of different statin intensities on clinical outcomes has never been assessed. We set out to determine the impact of statin exposure on cardiovascular outcomes after HT.Methods and resultsWe performed a retrospective study of 346 adult patients who underwent HT from 2006 to 2018. Statin intensity was determined longitudinally after HT based on American College of Cardiology/American Heart Association (ACC/AHA) guidelines. The primary outcome was the time to the first primary event defined as the composite of heart failure hospitalization, myocardial infarction, revascularization, and all‐cause mortality. Secondary outcomes included time to significant rejection and time to moderate–severe cardiac allograft vasculopathy. Adverse events were evaluated for subjects on high‐intensity statin therapy. A Cox proportional hazards model was used to evaluate the relationship between clinical variables, statin intensity, and outcomes. Most subjects were treated with low‐intensity statin therapy although this declined from 89.9% of the population at 1month after HT to 42.8% at 5years after HT. History of ischaemic cardiomyopathy, significant acute rejection, older donor age, and lesser statin intensity (p ≤ 0.001) were associated with reduced time to the primary outcome in a multivariable Cox model. Greater intensity of statin therapy was most beneficial early after HT. There were no statin‐related adverse events for the 14 subjects on high‐intensity statin therapy.ConclusionsGreater statin intensity was associated with a reduction in adverse cardiovascular outcomes after HT.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/162686/2/ehf212784.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/162686/1/ehf212784_am.pd

    Relating smoking, obesity, insulin resistance, and ovarian biomarker changes to the final menstrual period

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    To determine if smoking, obesity, and insulin resistance mediated age at final menstrual period (FMP), we examined anti-Müllerian hormone (AMH), inhibin B, and follicle-stimulating hormone (FSH) as biomarkers of changing follicle status and ovarian aging. We performed a longitudinal data analysis from a cohort of premenopausal women followed to their FMP. Our results found that smokers had an earlier age at FMP ( P < 0.003) and a more rapid decline in their AMH slope relative to age at FMP ( P < 0.002). Smokers had a lower baseline inhibin B level relative to age at the FMP than nonsmokers ( P = 0.002). Increasing insulin resistance was associated with a shorter time to FMP ( P < 0.003) and associations of obesity and time to FMP were observed ( P = 0.004, in model with FSH). Change in ovarian biomarkers did not mediate the time to FMP. We found that smoking was associated with age at FMP and modified associations of AMH and inhibin B with age at FMP. Insulin resistance was associated with shorter time to FMP independent of the biomarkers. Interventions targeting smoking and insulin resistance could curtail the undue advancement of reproductive aging.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/79293/1/j.1749-6632.2010.05523.x.pd

    KEDALAMAN KONSENTRASI KLOROFIL MAKSIMUM PERAIRAN SELATAN MALUKU BARAT DAYA DAN SEKITARNYA

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    Penelitian ini dilakukan untuk mengkaji kedalaman klorofil maksimum pada perairan selatan Maluku Barat Daya dan Sekitarnya. Penelitian dilakukan dengan menganalisa data hasil Ekspedisi ATSEA pada bulan Mei 2010. Data suhu, salinitas, oksigen dan klorofil perairan diamati dengan menggunakan CTD tipe SBE911+ pada lima stasiun pengamatan untuk setiap kedalaman hingga 500 m. Data dianalisis untuk mengkaji Pola sebaran vertikal dan melintang suhu, salinitas, oksigen dan klorofil, stratifikasi massa air, kedalaman klorofil maksimum dengan menggunakan perangkat lunak ODV versi 4 dan Mircosoft Office Excel. Hasil penelitian menunjukkan bahwa batas atas lapisan termoklin perairan berada pada kedalaman 44-60 m dan batas bawah lapisan termoklin pada kedalaman 325-409 m dengan ketebalan lapisan termoklin berkisar antara 267-352 m. Klorofil maksimum berada pada kedalaman 50-68 m yang berkisar antara 0,47-0,81 mg/m3 dengan rerata 0,59±0,13 mg/m3. Kedalaman klorofil maksimum dicirikan dengan suhu perairan 27,10-28,50 oC, salinitas 23,09-34,27 psu, dan konsentrasi oksigen 3,68-5,68 mg/l. Dengan demikian kedalaman klorofil maksimun berada pada bagian atas lapisan termoklin yakni beberapa meter di bawah batas atas lapisan termokli

    P5A-Type ATPase Cta4p Is Essential for Ca2+ Transport in the Endoplasmic Reticulum of Schizosaccharomyces pombe

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    This study establishes the role of P5A-type Cta4 ATPase in Ca2+ sequestration in the endoplasmic reticulum by detecting an ATP-dependent, vanadate-sensitive and FCCP insensitive 45Ca2+-transport in fission yeast membranes isolated by cellular fractionation. Specifically, the Ca2+-ATPase transport activity was decreased in ER membranes isolated from cells lacking a cta4+ gene. Furthermore, a disruption of cta4+ resulted in 6-fold increase of intracellular Ca2+ levels, sensitivity towards accumulation of misfolded proteins in ER and ER stress, stimulation of the calcineurin phosphatase activity and vacuolar Ca2+ pumping. These data provide compelling biochemical evidence for a P5A-type Cta4 ATPase as an essential component of Ca2+ transport system and signaling network which regulate, in conjunction with calcineurin, the ER functionality in fission yeast

    Antagonistic regulation of Fus2p nuclear localization by pheromone signaling and the cell cycle

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    When yeast cells sense mating pheromone, they undergo a characteristic response involving changes in transcription, cell cycle arrest in early G1, and polarization along the pheromone gradient. Cells in G2/M respond to pheromone at the transcriptional level but do not polarize or mate until G1. Fus2p, a key regulator of cell fusion, localizes to the tip of the mating projection during pheromone-induced G1 arrest. Although Fus2p was expressed in G2/M cells after pheromone induction, it accumulated in the nucleus until after cell division. As cells arrested in G1, Fus2p was exported from the nucleus and localized to the nascent tip. Phosphorylation of Fus2p by Fus3p was required for Fus2p export; cyclin/Cdc28p-dependent inhibition of Fus3p during late G1 through S phase was sufficient to block exit. However, during G2/M, when Fus3p was activated by pheromone signaling, Cdc28p activity again blocked Fus2p export. Our results indicate a novel mechanism by which pheromone-induced proteins are regulated during the transition from mitosis to conjugation

    Functional Characterization of an Aspergillus fumigatus Calcium Transporter (PmcA) that Is Essential for Fungal Infection

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    Aspergillus fumigatus is a primary and opportunistic pathogen, as well as a major allergen, of mammals. The Ca+2-calcineurin pathway affects virulence, morphogenesis and antifungal drug action in A. fumigatus. Here, we investigated three components of the A. fumigatus Ca+2-calcineurin pathway, pmcA,-B, and -C, which encode calcium transporters. We demonstrated that CrzA can directly control the mRNA accumulation of the pmcA-C genes by binding to their promoter regions. CrzA-binding experiments suggested that the 5′-CACAGCCAC-3′ and 5′-CCCTGCCCC-3′ sequences upstream of pmcA and pmcC genes, respectively, are possible calcineurin-dependent response elements (CDREs)-like consensus motifs. Null mutants were constructed for pmcA and -B and a conditional mutant for pmcC demonstrating pmcC is an essential gene. The ΔpmcA and ΔpmcB mutants were more sensitive to calcium and resistant to manganese and cyclosporin was able to modulate the sensitivity or resistance of these mutants to these salts, supporting the interaction between calcineurin and the function of these transporters. The pmcA-C genes have decreased mRNA abundance into the alveoli in the ΔcalA and ΔcrzA mutant strains. However, only the A. fumigatus ΔpmcA was avirulent in the murine model of invasive pulmonary aspergillosis

    Regulation of the Na+/K+-ATPase Ena1 Expression by Calcineurin/Crz1 under High pH Stress: A Quantitative Study

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    [EN] Regulated expression of the Ena1 Na+-ATPase is a crucial event for adaptation to high salt and/or alkaline pH stress in the budding yeast Saccharomyces cerevisiae. ENA1 expression is under the control of diverse signaling pathways, including that mediated by the calcium-regulatable protein phosphatase calcineurin and its downstream transcription factor Crz1. We present here a quantitative study of the expression of Ena1 in response to alkalinization of the environment and we analyze the contribution of Crz1 to this response. Experimental data and mathematical models substantiate the existence of two stress-responsive Crz1-binding sites in the ENA1 promoter and estimate that the contribution of Crz1 to the early response of the ENA1 promoter is about 60%. The models suggest the existence of a second input with similar kinetics, which would be likely mediated by high pH-induced activation of the Snf1 kinase.This work was supported by grants BFU2011-30197-C3-01, BFU2014-54591-C2-1-P and EUI2009-04147 (SysMo2) to JA. (Ministry of Industry and Competitivity, Spain, and Fondo Europeo de Desarrollo Regional [FEDER]). JA is the recipient of an Ajut 2014SGR-4 award (Generalitat de Catalunya). DC was recipient of a predoctoral fellowship from the Spanish Ministry of Education. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.Petrezsélyová, S.; López-Malo, M.; Canadell, D.; Roque, A.; Serra-Cardona, A.; Marques Romero, MC.; Vilaprinyó, E.... (2016). Regulation of the Na+/K+-ATPase Ena1 Expression by Calcineurin/Crz1 under High pH Stress: A Quantitative Study. PLoS ONE. 11(6):e0158424-e0158424. https://doi.org/10.1371/journal.pone.0158424Se0158424e015842411
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