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

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

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

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

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

The value of follicle-stimulating hormone concentration and clinical findings as markers of the late menopausal transition

CONTEXT: The Stages of Reproductive Aging Workshop proposed bleeding and hormonal criteria for the menopausal transition, but operational definitions of hormone parameters were not specified. OBJECTIVE: This paper investigates the longitudinal relationship of annual serum FSH levels with four proposed bleeding criteria for the late menopausal transition in two cohort studies. The goal is to provide empirically based guidance regarding application of hormonal criteria that may be optimal for widespread application in clinical and research settings for assessing menopausal stage. DESIGN/SETTING: Prospective menstrual calendar and annual serum FSH data were collected from two population-based cohort studies: the Melbourne Women\u27s Midlife Health Project and the Study of Women\u27s Health Across the Nation. PARTICIPANTS: Participants in the study were 193 Melbourne Women\u27s Midlife Health Project and 2223 Study of Women\u27s Health Across the Nation women aged 42-57 yr at baseline who contributed 10 or more menstrual cycles and at least one annual serum FSH value. MAIN OUTCOME MEASURE(S): Association between bleeding criteria for the late menopausal transition and FSH was a main outcome measure. Associations of bleeding criteria, FSH, and hot flashes with the final menstrual period were also measured. RESULTS: A single FSH measure is an independent marker of the late menopausal transition, but FSH concentrations are less predictive of menopausal stage than any of four proposed bleeding criteria. Criterion FSH values for the late transition are similar across both studies. Experience of hot flashes adds no information in the presence of hormonal and bleeding criteria. CONCLUSIONS: An annual serum FSH concentration of 40 IU/liter could be incorporated, in conjunction with bleeding markers, into the Stages of Reproductive Aging Workshop paradigm for markers of the late menopausal transition

The mating-specific Gα interacts with a kinesin-14 and regulates pheromone-induced nuclear migration in budding yeast

As a budding yeast cell elongates toward its mating partner, cytoplasmic microtubules connect the nucleus to the cell cortex at the growth tip. The Kar3 kinesin-like motor protein is then thought to stimulate plus-end depolymerization of these microtubules, thus drawing the nucleus closer to the site where cell fusion and karyogamy will occur. Here, we show that pheromone stimulates a microtubule-independent interaction between Kar3 and the mating-specific Gα protein Gpa1 and that Gpa1 affects both microtubule orientation and cortical contact. The membrane localization of Gpa1 was found to polarize early in the mating response, at about the same time that the microtubules begin to attach to the incipient growth site. In the absence of Gpa1, microtubules lose contact with the cortex upon shrinking and Kar3 is improperly localized, suggesting that Gpa1 is a cortical anchor for Kar3. We infer that Gpa1 serves as a positional determinant for Kar3-bound microtubule plus ends during mating. © 2009 by The American Society for Cell Biology

Synthetic Morphology Using Alternative Inputs

Designing the shape and size of a cell is an interesting challenge for synthetic biology. Prolonged exposure to the mating pheromone α-factor induces an unusual morphology in yeast cells: multiple mating projections. The goal of this work was to reproduce the multiple projections phenotype in the absence of α-factor using a gain-of-function approach termed “Alternative Inputs (AIs)”. An alternative input is defined as any genetic manipulation that can activate the signaling pathway instead of the natural input. Interestingly, none of the alternative inputs were sufficient to produce multiple projections although some produced a single projection. Then, we extended our search by creating all combinations of alternative inputs and deletions that were summarized in an AIs-Deletions matrix. We found a genetic manipulation (AI-Ste5p ste2Δ) that enhanced the formation of multiple projections. Following up this lead, we demonstrated that AI-Ste4p and AI-Ste5p were sufficient to produce multiple projections when combined. Further, we showed that overexpression of a membrane-targeted form of Ste5p alone could also induce multiple projections. Thus, we successfully re-engineered the multiple projections mating morphology using alternative inputs without α-factor

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

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

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