150 research outputs found
The regulation of the serum response network by the RGS RHOGEFS is critical for YAP1 activity and cell fate decisions
Indiana University-Purdue University Indianapolis (IUPUI)The growth of mammary epithelial cells is regulated by interactions with
neighboring cells and by exposure to soluble factors including hormones and growth
factors. These cues are integrated within the cell, perpetuating changes onto the
organization of the actin cytoskeleton, resulting in altered transcriptional programs. Rho
family GTPases regulates actin dynamics that facilitate transcriptional reprogramming. In
particular, RhoA induces the formation of actin stress fibers to promote the
transcriptional co-activator YAP1 to translocate from the cytosol into the nucleus. There,
it co-activates TEAD family transcription factors to drive the expression of pro-growth
and survival genes. Rho family members are activated by guanine exchange factors
(GEF) and inhibited by GTPase activating proteins (GAP). Here, we determined the
relative effects of expression of 67 RhoGEFs and RhoGAPs on the activation of TEAD.
This revealed that regulator of G-protein signaling (RGS) domain containing ArhGEF1,
ArhGEF11 and ArhGEF12 all promoted YAP1 dependent activation of TEAD. These
RhoGEFs mediate signaling from heptahelical receptors that are stimulated by lipid
mitogens to activate the heterotrimeric G-proteins Gα12 and Gα13. Consistently, loss of
expression of ArhGEF12 and to a lesser degree ArhGEF11 prevented actin stress fiber
accumulation and activation of YAP1 mediated signaling by serum. Conversely, several
complementary experiments revealed that ArhGEF1 dominantly limits Gα13 selective
activation of YAP1 and the mitogen activated protein kinase (MAPK) cascades.
Furthermore excessive Gα13 activity results in both high levels of filamentous actin and arrest cells in the G1/0 phase of the cell cycle. This is likely due to the systemic inhibition
of cell cycle promoting signaling and a loss of protein translation. Further, YAP1 was
found to be essential for the survival of ArhGEF1 silenced cells. Together, these studies
define a circuit whereby the rgRhoGEFs regulate Gα 12/13-RhoA signaling flux to regulate
cellular growth that is promoted by serum factors
Religious but not ethical: The effects of extrinsic religiosity, ethnocentrism and self-righteousness on consumers' ethical judgements
The current research investigates how religiosity can influence unethicality in a consumption context. In particular, considering the link between extrinsic religious orientations and unethicality, this research clarifies why and when extrinsic religiosity leads to unethical decisions. Across two studies, findings show that ethnocentrism is both a mediator (Study 1) and a moderator (Studies 1 and 2) of the effects of extrinsic religiosity on consumers’ ethical judgments. This is because extrinsic religiosity leads to ethnocentrism, and in-group loyalty manifested through ethnocentrism increases support for unethical consumer actions, thus establishing ethnocentrism as a mediator. At the same time, different levels of ethnocentrism can also influence how extrinsic religiosity leads to supporting unethical consumption via self-righteousness, thus establishing ethnocentrism as a moderator. The findings from this research have significant implications for diverse stakeholders who have an interest in religiosity and consumer behavior
The RGS-RhoGEFs control the amplitude of YAP1 activation by serum
Actin-dependent mechanisms drive the nuclear translocation of Yap1 to enable its co-activation of transcription factors that induce pro-growth and survival programs. While Rho GTPases are necessary for the nuclear import of YAP1, the relevant Guanine Exchange Factors (GEFs) and GTPase Activating Proteins (GAPs) that connect this process to upstream signaling are not well defined. To this end, we measured the impact of expressing sixty-seven RhoGEFs and RhoGAPs on the YAP1 dependent activity of a TEAD element transcriptional reporter. Robust effects by all three members of the regulator of G-protein signaling (RGS) domain containing RhoGEFs (ArhGEF1, ArhGEF11 and ArhGEF12) prompted studies relating their known roles in serum signaling onto the regulation of Yap1. Under all conditions examined, ArhGEF12 preferentially mediated the activation of YAP1/TEAD by serum versus ArhGEF1 or ArhGEF11. Conversely, ArhGEF1 in multiple contexts inhibited both basal and serum elevated YAP1 activity through its GAP activity for Gα13. The sensitivity of such inhibition to cellular density and to low states of serum signaling supports that ArhGEF1 is a context dependent regulator of YAP1. Taken together, the relative activities of the RGS-RhoGEFs were found to dictate the degree to which serum signaling promotes YAP1 activity
Therapeutic Potential of Targeting the Oncogenic SHP2 Phosphatase
, The Src homology 2 domain containing
protein tyrosine phosphatase-2
(SHP2) is an oncogenic phosphatase associated with various kinds of
leukemia and solid tumors. Thus, there is substantial interest in
developing SHP2 inhibitors as potential anticancer and antileukemia
agents. Using a structure-guided and fragment-based library approach,
we identified a novel hydroxyindole carboxylic acid-based SHP2 inhibitor 11a-1, with an IC50 value of 200 nM
and greater than 5-fold selectivity against 20 mammalian PTPs. Structural
and modeling studies reveal that the hydroxyindole carboxylic acid
anchors the inhibitor to the SHP2 active site, while interactions
of the oxalamide linker and the phenylthiophene tail with residues
in the β5–β6 loop contribute
to 11a-1’s binding potency and selectivity.
Evidence suggests that 11a-1 specifically
attenuates the SHP2-dependent signaling inside the cell. Moreover, 11a-1 blocks growth factor mediated Erk1/2 and
Akt activation and exhibits excellent antiproliferative activity in
lung cancer and breast cancer as well as leukemia cell lines
Integrating Ion Mobility Mass Spectrometry with Molecular Modelling to Determine the Architecture of Multiprotein Complexes
Current challenges in the field of structural genomics point to the need for new tools and technologies for obtaining structures of macromolecular protein complexes. Here, we present an integrative computational method that uses molecular modelling, ion mobility-mass spectrometry (IM-MS) and incomplete atomic structures, usually from X-ray crystallography, to generate models of the subunit architecture of protein complexes. We begin by analyzing protein complexes using IM-MS, and by taking measurements of both intact complexes and sub-complexes that are generated in solution. We then examine available high resolution structural data and use a suite of computational methods to account for missing residues at the subunit and/or domain level. High-order complexes and sub-complexes are then constructed that conform to distance and connectivity constraints imposed by IM-MS data. We illustrate our method by applying it to multimeric protein complexes within the Escherichia coli replisome: the sliding clamp, (β2), the γ complex (γ3δδ′), the DnaB helicase (DnaB6) and the Single-Stranded Binding Protein (SSB4)
Preventing and Treating Women’s Postpartum Depression: A Qualitative Systematic Review on Partner-Inclusive Interventions
Partner-related factors associated with the occurrence of Postpartum Depression (PPD) may justify the partner’s inclusion in preventive and treatment approaches. The aim of this qualitative systematic review was to synthesize the literature on partner-inclusive interventions designed to prevent or treat postpartum depression (PPD) in women. In accordance with the PRISMA guidelines, the systematic search of studies published between 1967 and May 2015 in PsycINFO and PubMed identified 26 studies that met the inclusion criteria, which reported on 24 interventions. The following partner parameters were analyzed: participation type, session content, mental health assessment, attendance assessment, and the effects of partner’s participation on the women’s response to the interventions. Total participation by the partner was mostly reported in the prevention studies, whereas partial participation was reported in the treatment studies. The session content was mostly based on psychoeducation about PPD and parenthood, coping strategies to facilitate the transition to parenthood such as the partner’s emotional and instrumental support, and problem-solving and communication skills. Some benefits perceived by the couples underscore the relevance of the partner’s inclusion in PPD interventions. However, the scarce information about the partner’s attendance and the associated effects on the women’s intervention outcomes, along with methodological limitations of the studies, made it difficult to determine if the partner’s participation was associated with the intervention’s efficacy. Conclusions about the clinical value of including partners in PPD interventions are still limited. More research is warranted to better inform health policy strategies
Capturing Single Cell Genomes of Active Polysaccharide Degraders: An Unexpected Contribution of Verrucomicrobia
Microbial hydrolysis of polysaccharides is critical to ecosystem functioning and is of great interest in diverse biotechnological applications, such as biofuel production and bioremediation. Here we demonstrate the use of a new, efficient approach to recover genomes of active polysaccharide degraders from natural, complex microbial assemblages, using a combination of fluorescently labeled substrates, fluorescence-activated cell sorting, and single cell genomics. We employed this approach to analyze freshwater and coastal bacterioplankton for degraders of laminarin and xylan, two of the most abundant storage and structural polysaccharides in nature. Our results suggest that a few phylotypes of Verrucomicrobia make a considerable contribution to polysaccharide degradation, although they constituted only a minor fraction of the total microbial community. Genomic sequencing of five cells, representing the most predominant, polysaccharide-active Verrucomicrobia phylotype, revealed significant enrichment in genes encoding a wide spectrum of glycoside hydrolases, sulfatases, peptidases, carbohydrate lyases and esterases, confirming that these organisms were well equipped for the hydrolysis of diverse polysaccharides. Remarkably, this enrichment was on average higher than in the sequenced representatives of Bacteroidetes, which are frequently regarded as highly efficient biopolymer degraders. These findings shed light on the ecological roles of uncultured Verrucomicrobia and suggest specific taxa as promising bioprospecting targets. The employed method offers a powerful tool to rapidly identify and recover discrete genomes of active players in polysaccharide degradation, without the need for cultivation
ReishiMax, mushroom based dietary supplement, inhibits adipocyte differentiation, stimulates glucose uptake and activates AMPK
<p>Abstract</p> <p>Background</p> <p>Obesity is a health hazard which is closely associated with various complications including insulin resistance, hypertension, dyslipidemia, atherosclerosis, type 2 diabetes and cancer. In spite of numerous preclinical and clinical interventions, the prevalence of obesity and its related disorders are on the rise demanding an urgent need for exploring novel therapeutic agents that can regulate adipogenesis. In the present study, we evaluated whether a dietary supplement ReishiMax (RM), containing triterpenes and polysaccharides extracted from medicinal mushroom <it>Ganoderma lucidum</it>, affects adipocyte differentiation and glucose uptake in 3T3-L1 cells.</p> <p>Methods</p> <p>3T3-L1 pre-adipocytes were differentiated into adipocytes and treated with RM (0-300 μg/ml). Adipocyte differentiation/lipid uptake was evaluated by oil red O staining and triglyceride and glycerol concentrations were determined. Gene expression was evaluated by semi-quantitative RT-PCR and Western blot analysis. Glucose uptake was determined with [<sup>3</sup>H]-glucose.</p> <p>Results</p> <p>RM inhibited adipocyte differentiation through the suppresion of expression of adipogenic transcription factors peroxisome proliferator-activated receptor-γ (PPAR-γ), sterol regulatory element binding element protein-1c (SREBP-1c) and CCAAT/enhancer binding protein-α (C/EBP-α). RM also suppressed expression of enzymes and proteins responsible for lipid synthesis, transport and storage: fatty acid synthase (FAS), acyl-CoA synthetase-1 (ACS1), fatty acid binding protein-4 (FABP4), fatty acid transport protein-1 (FATP1) and perilipin. RM induced AMP-activated protein kinase (AMPK) and increased glucose uptake by adipocytes.</p> <p>Conclusion</p> <p>Our study suggests that RM can control adipocyte differentiation and glucose uptake. The health benefits of ReishiMax warrant further clinical studies.</p
Measurement of associated Z plus charm production in proton-proton collisions at root s=8TeV
A study of the associated production of a Z boson and a charm quark jet (Z + c), and a comparison to production with a b quark jet (Z + b), in pp collisions at a centre-of-mass energy of 8 TeV are presented. The analysis uses a data sample corresponding to an integrated luminosity of 19.7 fb(-1), collected with the CMS detector at the CERN LHC. The Z boson candidates are identified through their decays into pairs of electrons or muons. Jets originating from heavy flavour quarks are identified using semileptonic decays of c or b flavoured hadrons and hadronic decays of charm hadrons. The measurements are performed in the kinematic region with two leptons with pT(l) > 20 GeV, vertical bar eta(l)vertical bar 25 GeV and vertical bar eta(jet)vertical bar Z + c + X) B(Z -> l(+)l(-)) = 8.8 +/- 0.5 (stat)+/- 0.6 (syst) pb. The ratio of the Z+c and Z+b production cross sections is measured to be sigma(pp -> Z+c+X)/sigma (pp -> Z+b+X) = 2.0 +/- 0.2 (stat)+/- 0.2 (syst). The Z+c production cross section and the cross section ratio are also measured as a function of the transverse momentum of theZ boson and of the heavy flavour jet. The measurements are compared with theoretical predictions.Peer reviewe
Effect of SGLT2 inhibitors on stroke and atrial fibrillation in diabetic kidney disease: Results from the CREDENCE trial and meta-analysis
BACKGROUND AND PURPOSE: Chronic kidney disease with reduced estimated glomerular filtration rate or elevated albuminuria increases risk for ischemic and hemorrhagic stroke. This study assessed the effects of sodium glucose cotransporter 2 inhibitors (SGLT2i) on stroke and atrial fibrillation/flutter (AF/AFL) from CREDENCE (Canagliflozin and Renal Events in Diabetes With Established Nephropathy Clinical Evaluation) and a meta-Analysis of large cardiovascular outcome trials (CVOTs) of SGLT2i in type 2 diabetes mellitus. METHODS: CREDENCE randomized 4401 participants with type 2 diabetes mellitus and chronic kidney disease to canagliflozin or placebo. Post hoc, we estimated effects on fatal or nonfatal stroke, stroke subtypes, and intermediate markers of stroke risk including AF/AFL. Stroke and AF/AFL data from 3 other completed large CVOTs and CREDENCE were pooled using random-effects meta-Analysis. RESULTS: In CREDENCE, 142 participants experienced a stroke during follow-up (10.9/1000 patient-years with canagliflozin, 14.2/1000 patient-years with placebo; hazard ratio [HR], 0.77 [95% CI, 0.55-1.08]). Effects by stroke subtypes were: ischemic (HR, 0.88 [95% CI, 0.61-1.28]; n=111), hemorrhagic (HR, 0.50 [95% CI, 0.19-1.32]; n=18), and undetermined (HR, 0.54 [95% CI, 0.20-1.46]; n=17). There was no clear effect on AF/AFL (HR, 0.76 [95% CI, 0.53-1.10]; n=115). The overall effects in the 4 CVOTs combined were: Total stroke (HRpooled, 0.96 [95% CI, 0.82-1.12]), ischemic stroke (HRpooled, 1.01 [95% CI, 0.89-1.14]), hemorrhagic stroke (HRpooled, 0.50 [95% CI, 0.30-0.83]), undetermined stroke (HRpooled, 0.86 [95% CI, 0.49-1.51]), and AF/AFL (HRpooled, 0.81 [95% CI, 0.71-0.93]). There was evidence that SGLT2i effects on total stroke varied by baseline estimated glomerular filtration rate (P=0.01), with protection in the lowest estimated glomerular filtration rate (45 mL/min/1.73 m2]) subgroup (HRpooled, 0.50 [95% CI, 0.31-0.79]). CONCLUSIONS: Although we found no clear effect of SGLT2i on total stroke in CREDENCE or across trials combined, there was some evidence of benefit in preventing hemorrhagic stroke and AF/AFL, as well as total stroke for those with lowest estimated glomerular filtration rate. Future research should focus on confirming these data and exploring potential mechanisms
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