The G12/13 class of heterotrimeric G proteins, comprising the α-subunits Gα12 and Gα13, regulates multiple aspects of cellular behavior, including proliferation and cytoskeletal rearrangements. ...Although guanine nucleotide exchange factors for the monomeric G protein Rho (RhoGEFs) are well characterized as effectors of this G protein class, a variety of other downstream targets has been reported. To identify Gα12 determinants that mediate specific protein interactions, we used a structural and evolutionary comparison between the G12/13, Gs, Gi, and Gq classes to identify "class-distinctive" residues in Gα12 and Gα13. Mutation of these residues in Gα12 to their deduced ancestral forms revealed a subset necessary for activation of serum response element (SRE)-mediated transcription, a G12/13-stimulated pathway implicated in cell proliferative signaling. Unexpectedly, this subset of Gα12 mutants showed impaired binding to heat-shock protein 90 (Hsp90) while retaining binding to RhoGEFs. Corresponding mutants of Gα13 exhibited robust SRE activation, suggesting a Gα12-specific mechanism, and inhibition of Hsp90 by geldanamycin or small interfering RNA-mediated lowering of Hsp90 levels resulted in greater downregulation of Gα12 than Gα13 signaling in SRE activation experiments. Furthermore, the Drosophila G12/13 homolog Concertina was unable to signal to SRE in mammalian cells, and Gα12:Concertina chimeras revealed Gα12-specific determinants of SRE activation within the switch regions and a C-terminal region. These findings identify Gα12 determinants of SRE activation, implicate Gα12:Hsp90 interaction in this signaling mechanism, and illuminate structural features that arose during evolution of Gα12 and Gα13 to allow bifurcated mechanisms of signaling to a common cell proliferative pathway.
Concentrated chemical spills have been shown to impact adversely on fish populations and even cause localized population extinctions. Evaluating population‐level impacts of sublethal exposure ...concentrations is, however, complex and confounded by other environmental pressures. Applying effect measures derived from laboratory‐based chemical exposures to impacts in wild fish populations is constrained by uncertainty on how biochemical response measures (biomarkers) translate into health outcomes, lack of available data for chronic exposures and the many uncertainties in available fish population models. Furthermore, wild fish show phenotypic plasticity and local adaptations can occur that adds geographic and temporal variance on responses. Such population‐level factors are rarely considered in the chemical risk assessment process and can probably be derived only from studies on wild fish. Molecular technologies, including microsatellite and SNP genotyping, and RNASeq for gene expression studies, are advancing our understanding of mechanisms of eco‐toxicological response, tolerance, adaptation and selection in wild populations. We examine critically the application of such approaches with examples including using microsatellites that has identified roach (Rutilus rutilus) populations living in rivers contaminated with sewage effluents that are self‐sustaining, and studies of stickleback (Gasterosteus aculeatus) and killifish (Fundulus heteroclitus) that have identified genomic regions under selection putatively related to pollution tolerance. Integrating data on biological effects between laboratory‐based studies and wild populations, and building understanding on adaptive responses to sublethal exposure are some of the priority research areas for more effective evaluation of population risks and resilience to contaminant exposure.
The Pluto system was recently explored by NASA's New Horizons spacecraft, making closest approach on 14 July 2015. Pluto's surface displays diverse landforms, terrain ages, albedos, colors, and ...composition gradients. Evidence is found for a water-ice crust, geologically young surface units, surface ice convection, wind streaks, volatile transport, and glacial flow. Pluto's atmosphere is highly extended, with trace hydrocarbons, a global haze layer, and a surface pressure near 10 microbars. Pluto's diverse surface geology and long-term activity raise fundamental questions about how small planets remain active many billions of years after formation. Pluto's large moon Charon displays tectonics and evidence for a heterogeneous crustal composition; its north pole displays puzzling dark terrain. Small satellites Hydra and Nix have higher albedos than expected.
Background: The feminization of nature by endocrine-disrupting chemicals (EDCs) is a key environmental issue affecting both terrestrial and aquatic wildlife. A crucial and as yet unanswered question ...is whether EDCs have adverse impacts on the sustainability of wildlife populations. There is widespread concern that intersex fish are reproductively compromised, with potential populationlevel consequences. However, to date, only in vitro sperm quality data are available in support of this hypothesis. Objective: The aim of this study was to examine whether wild endocrine-disrupted fish can compete successfully in a realistic breeding scenario. Methods: In two competitive breeding experiments using wild roach (Rutilus rutilus), we used DNA microsatellites to assign parentage and thus determine reproductive success of the adults. Results: In both studies, the majority of intersex fish were able to breed, albeit with varying degrees of success. In the first study, where most intersex fish were only mildly feminized, body length was the only (actor correlated with reproductive success. In the second study, which included a higher number of more severely intersex fish, reproductive performance was negatively correlated with severity of intersex. The intersex condition reduced reproductive performance by up to 76% for the most feminized individuals in this study, demonstrating a significant adverse effect of intersex on reproductive performance. Conclusion: Feminization of male fish is likely to be an important determinant of reproductive performance in rivers where there is a high prevalence of moderately to severely feminized males.
We present a whole-cell fully dynamical kinetic model (WCM) of JCVI-syn3A, a minimal cell with a reduced genome of 493 genes that has retained few regulatory proteins or small RNAs. Cryo-electron ...tomograms provide the cell geometry and ribosome distributions. Time-dependent behaviors of concentrations and reaction fluxes from stochastic-deterministic simulations over a cell cycle reveal how the cell balances demands of its metabolism, genetic information processes, and growth, and offer insight into the principles of life for this minimal cell. The energy economy of each process including active transport of amino acids, nucleosides, and ions is analyzed. WCM reveals how emergent imbalances lead to slowdowns in the rates of transcription and translation. Integration of experimental data is critical in building a kinetic model from which emerges a genome-wide distribution of mRNA half-lives, multiple DNA replication events that can be compared to qPCR results, and the experimentally observed doubling behavior.
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•3D spatial resolution of a fully dynamical whole-cell kinetic model•Detailed single-reaction, single-cell accounting of time-dependent ATP costs•Genome-wide mRNA half-lives emerge from length-dependent kinetics and diffusion•Connections among metabolism, genetic information, and cell growth are revealed
A kinetic model for a minimal bacterial cell offers quantitative insight into how the cell balances processes from metabolism to gene expression to growth.
The role of relatedness in structuring animal societies has attracted considerable interest. Whilst a significant number of studies have documented kin recognition in shoaling fish under laboratory ...conditions, there is little evidence that relatedness plays a significant role in structuring social interactions in wild populations that are characterised by fission-fusion dynamics. Previous work has tended to compare relatedness within and among entire shoals. Such an approach however, does not have the ability to detect social sub-structuring within groups, which appears to be a major factor driving the social organisation of fission-fusion animal societies. Here, we use social network analysis combined with DNA microsatellite genotyping to examine the role of relatedness in structuring social relationships in a wild population of guppies (Poecilia reticulata). Consistent with previous findings, femalefemale dyads formed the strongest social relationships, which were stable over time. Interestingly, we also observed significant co-occurrence of male-male interactions, which is in contrast to previous work. Although we observed social sub-structuring in the population, we found no evidence for relatedness playing a significant role in underpinning this structure. Indeed, only seven first-degree relative dyads were identified among the 180 fish genotyped, indicating that the majority of individuals do not have a first-degree relative in the population. The high genetic diversity observed in this population is indicative of a large effective population size typical of lowland guppy populations. We discuss our findings in the context of the evolution of social organisation and the mechanisms and constraints that may drive the observed patterns in wild populations.
High-grade serous ovarian cancer (HGSC) exhibits extensive malignant clonal diversity with widespread but non-random patterns of disease dissemination. We investigated whether local immune ...microenvironment factors shape tumor progression properties at the interface of tumor-infiltrating lymphocytes (TILs) and cancer cells. Through multi-region study of 212 samples from 38 patients with whole-genome sequencing, immunohistochemistry, histologic image analysis, gene expression profiling, and T and B cell receptor sequencing, we identified three immunologic subtypes across samples and extensive within-patient diversity. Epithelial CD8+ TILs negatively associated with malignant diversity, reflecting immunological pruning of tumor clones inferred by neoantigen depletion, HLA I loss of heterozygosity, and spatial tracking between T cell and tumor clones. In addition, combinatorial prognostic effects of mutational processes and immune properties were observed, illuminating how specific genomic aberration types associate with immune response and impact survival. We conclude that within-patient spatial immune microenvironment variation shapes intraperitoneal malignant spread, provoking new evolutionary perspectives on HGSC clonal dispersion.
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•Immune infiltrates vary across space within patients at the time of diagnosis•Immune infiltration shapes malignant cell evolutionary trajectories•T cell clones track with tumor clones across spatial sites within patients•Immune infiltrates and mutational processes show prognostic interactions
Integrated multi-region analysis of metastatic sites in patients with high-grade ovarian cancer highlights the connection between immune microenvironment variation and malignant spread, as well as the combinatorial prognostic value of immune and mutational features.
Feminized responses are widespread in wild populations of roach, Rutilus rutilus, living in UK rivers, and some of these responses have been shown to arise as a consequence of exposure to wastewater ...treatment works (WwTW) effluent discharges and the endocrine disrupting chemicals (EDCs) they contain. The causation of the ovotestis condition in wild roach, however, has yet to be established. Furthermore, the impact of long-term exposure to WwTW effluents on the reproductive fitness of wild fish populations is not known, and this information is crucial for population level effect assessments. We undertook a chronic exposure of roach to a treated estrogenic wastewater effluent for up to 3.5 years to assess principally for effects on subsequent reproductive fitness, as determined through parentage analysis on offspring from a competitive breeding study. In generating the fish for the breeding study we found that exposure to full strength WwTW effluent until sexual maturity resulted in sex reversal in almost all males in the population; 98% of the exposed fish were phenotypic females, containing ovaries. Furthermore, fish exposed to a 50% dilution of WwTW effluent contained ovotestis (21% of the male roach) that was absent from the control population. In competitive breeding studies, and applying DNA microsatellites to assess parentage, we show that presumptive females exposed to sexual maturity to WwTW effluent bred normally, albeit in the absence of nonexposed females, but putative sex-reversed males breeding as females contributed poorly, if at all, in a breeding population, depending on the competition. These novel findings on sex reversal add a new dimension for impact assessments of exposure to WwTW effluents on fish populations.
BACKGROUNDPeriarticular injection (PAI) is administered intraoperatively to help reduce postoperative pain and opioid consumption after primary total joint arthroplasty (TJA). The purpose of this ...study was to evaluate the efficacy and safety of PAI in primary TJA to support the combined clinical practice guidelines of the American Association of Hip and Knee Surgeons, American Academy of Orthopaedic Surgeons, Hip Society, Knee Society, and American Society of Regional Anesthesia and Pain Medicine. METHODSThe MEDLINE, Embase, and Cochrane Central Register of Controlled Trials databases were searched for studies published prior to March 2020 on PAI in TJA. All included studies underwent qualitative and quantitative homogeneity testing followed by a systematic review and direct comparison meta-analysis to assess the efficacy and safety of PAI. RESULTSThree thousand six hundred and ninety nine publications were critically appraised to provide 60 studies regarded as the best available evidence for an analysis. The meta-analysis showed that intraoperative PAI reduces postoperative pain and opioid consumption. Adding ketorolac or a corticosteroid to a long-acting local anesthetic (eg, ropivacaine or bupivacaine) provides an additional benefit. There is no difference between liposomal bupivacaine and other nonliposomal long-acting local anesthetics. Morphine does not provide any additive benefit in postoperative pain and opioid consumption and may increase postoperative nausea and vomiting. There is insufficient evidence to draw conclusions on the use of epinephrine and clonidine. CONCLUSIONStrong evidence supports the use of a PAI with a long-acting local anesthetic to reduce postoperative pain and opioid consumption. Adding a corticosteroid and/or ketorolac to a long-acting local anesthetic further reduces postoperative pain and may reduce opioid consumption. Morphine has no additive effect and there is insufficient evidence on epinephrine and clonidine.
BACKGROUNDCorticosteroids are commonly used intraoperatively to treat pain and reduce opioid consumption and nausea associated with primary total joint arthroplasty (TJA). The purpose of this study ...was to evaluate the efficacy and safety of corticosteroids in primary TJA to support the combined clinical practice guidelines of the American Association of Hip and Knee Surgeons, American Academy of Orthopaedic Surgeons, Hip Society, Knee Society, and the American Society of Regional Anesthesia and Pain Management. METHODSThe MEDLINE, Embase, and Cochrane Central Register of Controlled Trials databases were searched for studies published before February 2020 on corticosteroids in TJA. All included studies underwent qualitative and quantitative homogeneity testing followed by a systematic review and direct comparison meta-analysis to assess the efficacy and safety of corticosteroids. RESULTSCritical appraisal of 1,581 publications revealed 23 studies regarded as the best available evidence for analysis. Intraoperative dexamethasone reduces postoperative pain, opioid consumption, and nausea and vomiting. Multiple doses lead to further reduction in pain, opioid consumption, nausea and vomiting. There is insufficient evidence on the risk of adverse events with perioperative dexamethasone in TJA. CONCLUSIONStrong evidence supports the use of a single dose or multiple doses of intravenous dexamethasone to reduce postoperative pain, opioid consumption, nausea and vomiting after primary TJA. There is insufficient evidence on perioperative dexamethasone in primary TJA to determine the optimal dose, number of doses, or risk of postoperative adverse events.
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