115 research outputs found

    Multicopper oxidase-1 is a ferroxidase essential for iron homeostasis in Drosophila melanogaster

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    Multicopper ferroxidases catalyze the oxidation of ferrous iron to ferric iron. In yeast and algae, they participate in cellular uptake of iron; in mammals, they facilitate cellular efflux. The mechanisms of iron metabolism in insects are still poorly understood, and insect multicopper ferroxidases have not been identified. In this paper we present evidence that Drosophila melanogaster multicopper oxidase-1 (MCO1) is a functional ferroxidase. We identified candidate iron binding residues in the MCO1 sequence and found that purified recombinant MCO1 oxidizes ferrous iron. An association between MCO1 function and iron homeostasis was confirmed by two observations: RNAi-mediated knockdown of MCO1 resulted in decreased iron accumulation in midguts and whole insects, and weak knockdown increased the longevity of flies fed a toxic concentration of iron. Strong knockdown of MCO1 resulted in pupal lethality, indicating that MCO1 is an essential gene. Immunohistochemistry experiments demonstrated that MCO1 is located on the basal surfaces of the digestive system and Malpighian tubules. We propose that MCO1 oxidizes ferrous iron in the hemolymph and that the resulting ferric iron is bound by transferrin or melanotransferrin leading to iron storage, iron withholding from pathogens, regulation of oxidative stress and/or epithelial maturation. These proposed functions are distinct from those of other known ferroxidases Given that MCO1 orthologs are present in all insect genomes analyzed to date, this discovery is an important step toward understanding iron metabolism in insects

    The Future of Library Services for & with Teens: A Call to Action

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    As part of the year-long National Forum on Libraries and Teens effort, YALSA has released a report, "The Future of Library Services for and with Teens: A Call to Action" providing direction on how libraries need to adapt and change to meet the needs of 21st century teens.The report is a call to action for the library community. It provides recommendations on how libraries must address challenges and re-envision their teen services in order to meet the needs of their individual communities and to collectively ensure that the nation's 40+ million teens develop the skills they need to be productive citizens. By acting on this call, the library community can work within their own local communities to create the kind of spaces, services, and opportunities that today's teens need in order to succeed in school and in life

    Executive Summary for The Future of Library Services for and with Teens: A Call to Action

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    As part of the year-long National Forum on Libraries and Teens effort, YALSA has released a report, "The Future of Library Services for and with Teens: A Call to Action" providing direction on how libraries need to adapt and change to meet the needs of 21st century teens. The report is a call to action for the library community. It provides recommendations on how libraries must address challenges and re-envision their teen services in order to meet the needs of their individual communities and to collectively ensure that the nation's 40+ million teens develop the skills they need to be productive citizens. By acting on this call, the library community can work within their own local communities to create the kind of spaces, services, and opportunities that today's teens need in order to succeed in school and in life

    Autism Spectrum Disorder Among US Children (2002–2010): Socioeconomic, Racial, and Ethnic Disparities

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    Objectives. To describe the association between indicators of socioeconomic status (SES) and the prevalence of autism spectrum disorder (ASD) in the United States during the period 2002 to 2010, when overall ASD prevalence among children more than doubled, and to determine whether SES disparities account for ongoing racial and ethnic disparities in ASD prevalence

    Increased MCL1 dependency leads to new applications of BH3-mimetics in drug-resistant neuroblastoma.

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    Neuroblastoma is a paediatric cancer that is characterised by poor prognosis for chemoresistant disease, highlighting the need for better treatment options. Here, we asked whether BH3-mimetics inhibiting BCL2 proteins may eliminate chemoresistant neuroblastoma cells. We utilised cisplatin-adapted neuroblastoma cell lines as well as patient tissues before and after relapse to study alterations of BCL2 proteins upon chemoresistance. In a direct comparison of cisplatin-resistant cells we identified a prominent loss of sensitivity to BCL2/BCL-X inhibitors that is associated with an increase in MCL1 dependency and high expression of MCL1 in patient tumour tissues. Screening of FDA-approved anti-cancer drugs in chemoresistant cells identified therapeutics that may be beneficial in combination with the clinically tested BH3-mimetic ABT263, but no synergistic drug interactions with the selective MCL1 inhibitor S63845. Further exploration of potential treatment options for chemoresistant neuroblastoma identified immunotherapy based on NK cells as highly promising, since NK cells are able to efficiently kill both parental and chemoresistant cells. These data highlight that the application of BH3-mimetics may differ between first line treatment and relapsed disease. Combination of NK cell-based immunotherapy with BH3-mimetics may further increase killing of chemoresistant neuroblastoma, outlining a new treatment strategy for relapsed neuroblastoma. [Abstract copyright: © 2023. The Author(s).

    Plasma membrane-targeted PIN proteins drive shoot development in a moss.

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    BACKGROUND: Plant body plans arise by the activity of meristematic growing tips during development and radiated independently in the gametophyte (n) and sporophyte (2n) stages of the life cycle during evolution. Although auxin and its intercellular transport by PIN family efflux carriers are primary regulators of sporophytic shoot development in flowering plants, the extent of conservation in PIN function within the land plants and the mechanisms regulating bryophyte gametophytic shoot development are largely unknown. RESULTS: We have found that treating gametophytic shoots of the moss Physcomitrella patens with exogenous auxins and auxin transport inhibitors disrupts apical function and leaf development. Two plasma membrane-targeted PIN proteins are expressed in leafy shoots, and pin mutants resemble plants treated with auxins or auxin transport inhibitors. PIN-mediated auxin transport regulates apical cell function, leaf initiation, leaf shape, and shoot tropisms in moss gametophytes. pin mutant sporophytes are sometimes branched, reproducing a phenotype only previously seen in the fossil record and in rare natural moss variants. CONCLUSIONS: Our results show that PIN-mediated auxin transport is an ancient, conserved regulator of shoot development.C.J.H. is funded by a Royal Society University Research Fellowship, a Gatsby Charitable Foundation fellowship (GAT2962) and the BBSRC (BB/L00224811) and R.R. is funded by the Deutsche Forschungsgemeinschaft (SPP 1067, RE 837/6) and the Excellence Initiative of the German Federal and State Governments (EXC294).This is the final version. It was first published by Elsevier at http://www.cell.com/current-biology/abstract/S0960-9822%2814%2901217-2

    GestaltMatcher Database - A global reference for facial phenotypic variability in rare human diseases

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    The most important factor that complicates the work of dysmorphologists is the significant phenotypic variability of the human face. Next-Generation Phenotyping (NGP) tools that assist clinicians with recognizing characteristic syndromic patterns are particularly challenged when confronted with patients from populations different from their training data. To that end, we systematically analyzed the impact of genetic ancestry on facial dysmorphism. For that purpose, we established the GestaltMatcher Database (GMDB) as a reference dataset for medical images of patients with rare genetic disorders from around the world. We collected 10,980 frontal facial images - more than a quarter previously unpublished - from 8,346 patients, representing 581 rare disorders. Although the predominant ancestry is still European (67%), data from underrepresented populations have been increased considerably via global collaborations (19% Asian and 7% African). This includes previously unpublished reports for more than 40% of the African patients. The NGP analysis on this diverse dataset revealed characteristic performance differences depending on the composition of training and test sets corresponding to genetic relatedness. For clinical use of NGP, incorporating non-European patients resulted in a profound enhancement of GestaltMatcher performance. The top-5 accuracy rate increased by +11.29%. Importantly, this improvement in delineating the correct disorder from a facial portrait was achieved without decreasing the performance on European patients. By design, GMDB complies with the FAIR principles by rendering the curated medical data findable, accessible, interoperable, and reusable. This means GMDB can also serve as data for training and benchmarking. In summary, our study on facial dysmorphism on a global sample revealed a considerable cross ancestral phenotypic variability confounding NGP that should be counteracted by international efforts for increasing data diversity. GMDB will serve as a vital reference database for clinicians and a transparent training set for advancing NGP technology.</p

    A communal catalogue reveals Earth's multiscale microbial diversity

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    Our growing awareness of the microbial world's importance and diversity contrasts starkly with our limited understanding of its fundamental structure. Despite recent advances in DNA sequencing, a lack of standardized protocols and common analytical frameworks impedes comparisons among studies, hindering the development of global inferences about microbial life on Earth. Here we present a meta-analysis of microbial community samples collected by hundreds of researchers for the Earth Microbiome Project. Coordinated protocols and new analytical methods, particularly the use of exact sequences instead of clustered operational taxonomic units, enable bacterial and archaeal ribosomal RNA gene sequences to be followed across multiple studies and allow us to explore patterns of diversity at an unprecedented scale. The result is both a reference database giving global context to DNA sequence data and a framework for incorporating data from future studies, fostering increasingly complete characterization of Earth's microbial diversity.Peer reviewe
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