33 research outputs found

    Three-dimensional architecture of the human BRCA1-A histone deubiquitinase core complex

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    BRCA1 is a tumor suppressor found to be mutated in hereditary breast and ovarian cancer and plays key roles in the maintenance of genomic stability by homologous recombination repair. It is recruited to damaged chromatin as a component of the BRCA1-A deubiquitinase, which cleaves K63-linked ubiquitin chains attached to histone H2A and H2AX. BRCA1-A contributes to checkpoint regulation, repair pathway choice, and HR repair efficiency through molecular mechanisms that remain largely obscure. The structure of an active core complex comprising two Abraxas/BRCC36/BRCC45/MERIT40 tetramers determined by negative-stain electron microscopy (EM) reveals a distorted V-shape architecture in which a dimer of Abraxas/BRCC36 heterodimers sits at the base, with BRCC45/Merit40 pairs occupying each arm. The location and ubiquitin-binding activity of BRCC45 suggest that it may provide accessory interactions with nucleosome-linked ubiquitin chains that contribute to their efficient processing. Our data also suggest how ataxia telangiectasia mutated (ATM)-dependent BRCA1 dimerization may stabilize self-association of the entire BRCA1-A complex

    The molecular basis of ATM-dependent dimerization of the Mdc1 DNA damage checkpoint mediator

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    Mdc1 is a large modular phosphoprotein scaffold that maintains signaling and repair complexes at double-stranded DNA break sites. Mdc1 is anchored to damaged chromatin through interaction of its C-terminal BRCT-repeat domain with the tail of γH2AX following DNA damage, but the role of the N-terminal forkhead-associated (FHA) domain remains unclear. We show that a major binding target of the Mdc1 FHA domain is a previously unidentified DNA damage and ATM-dependent phosphorylation site near the N-terminus of Mdc1 itself. Binding to this motif stabilizes a weak self-association of the FHA domain to form a tight dimer. X-ray structures of free and complexed Mdc1 FHA domain reveal a ‘head-to-tail' dimerization mechanism that is closely related to that seen in pre-activated forms of the Chk2 DNA damage kinase, and which both positively and negatively influences Mdc1 FHA domain-mediated interactions in human cells prior to and following DNA damag

    Occurrence and abundance of fruit bats in selected conservation areas of North Cotabato, Philippines

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    ABSTRACT A study on the occurrence and abundance of fruit bats (Pteropodidae) was done in two conservation areas in North Cotabato, Philippines: Portion of the Mt. Apo National Park ; Balabag, Kidapawan City and Cotabato Provincial Forest and Ecotourism Park (CPFEP), Amas, Kidapawan City. Seven species were recorded in CPFEP and six were noted in Balabag area identified from 449 individuals captured. Two species (Eonycteris spelaea and Rousettus amplexicaudatus) were unique to CPFEP while one (Ptenochirus minor) was found only in Balabag area. A total of eight species were recorded when accounting the species found in two areas in which, three are endemic to the country namely Haplonycteris fischeri, Ptenochirus jagori, and P. minor. Of these endemics, the first two were noted in CPFEP while all were found in Balabag area. More than half of the bats captured were Cynopterus brachyotis hence, considered as the most common species. Remarkable finding was the presence of Megaerops wetmorei, a threatened species, to have found in a new altitudinal record. Considering the importance of fruit bats in regenerating forest, urgent conservation measures are highly recommended

    The molecular basis of ATM-dependent dimerization of the Mdc1 DNA damage checkpoint mediator

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    Mdc1 is a large modular phosphoprotein scaffold that maintains signaling and repair complexes at double-stranded DNA break sites. Mdc1 is anchored to damaged chromatin through interaction of its C-terminal BRCT-repeat domain with the tail of γH2AX following DNA damage, but the role of the N-terminal forkhead-associated (FHA) domain remains unclear. We show that a major binding target of the Mdc1 FHA domain is a previously unidentified DNA damage and ATM-dependent phosphorylation site near the N-terminus of Mdc1 itself. Binding to this motif stabilizes a weak self-association of the FHA domain to form a tight dimer. X-ray structures of free and complexed Mdc1 FHA domain reveal a ‘head-to-tail’ dimerization mechanism that is closely related to that seen in pre-activated forms of the Chk2 DNA damage kinase, and which both positively and negatively influences Mdc1 FHA domain-mediated interactions in human cells prior to and following DNA damage

    Narcissism and the strategic pursuit of short-term mating : universal links across 11 world regions of the International Sexuality Description Project-2.

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    Previous studies have documented links between sub-clinical narcissism and the active pursuit of short-term mating strategies (e.g., unrestricted sociosexuality, marital infidelity, mate poaching). Nearly all of these investigations have relied solely on samples from Western cultures. In the current study, responses from a cross-cultural survey of 30,470 people across 53 nations spanning 11 world regions (North America, Central/South America, Northern Europe, Western Europe, Eastern Europe, Southern Europe, Middle East, Africa, Oceania, Southeast Asia, and East Asia) were used to evaluate whether narcissism (as measured by the Narcissistic Personality Inventory; NPI) was universally associated with short-term mating. Results revealed narcissism scores (including two broad factors and seven traditional facets as measured by the NPI) were functionally equivalent across cultures, reliably associating with key sexual outcomes (e.g., more active pursuit of short-term mating, intimate partner violence, and sexual aggression) and sex-related personality traits (e.g., higher extraversion and openness to experience). Whereas some features of personality (e.g., subjective well-being) were universally associated with socially adaptive facets of Narcissism (e.g., self-sufficiency), most indicators of short-term mating (e.g., unrestricted sociosexuality and marital infidelity) were universally associated with the socially maladaptive facets of narcissism (e.g., exploitativeness). Discussion addresses limitations of these cross-culturally universal findings and presents suggestions for future research into revealing the precise psychological features of narcissism that facilitate the strategic pursuit of short-term mating

    Integrative Analysis of the Caenorhabditis elegans Genome by the modENCODE Project

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    We systematically generated large-scale data sets to improve genome annotation for the nematode Caenorhabditis elegans, a key model organism. These data sets include transcriptome profiling across a developmental time course, genome-wide identification of transcription factor-binding sites, and maps of chromatin organization. From this, we created more complete and accurate gene models, including alternative splice forms and candidate noncoding RNAs. We constructed hierarchical networks of transcription factor-binding and microRNA interactions and discovered chromosomal locations bound by an unusually large number of transcription factors. Different patterns of chromatin composition and histone modification were revealed between chromosome arms and centers, with similarly prominent differences between autosomes and the X chromosome. Integrating data types, we built statistical models relating chromatin, transcription factor binding, and gene expression. Overall, our analyses ascribed putative functions to most of the conserved genome

    Narcisismo y búsqueda estratégica del emparejamiento a corto plazo a través de las culturas: Enlaces omnipresentes a través de 11 regiones mundiales del Proyecto de la descripción de la sexualidad internacional 2

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    Previous studies have documented links between sub-clinical narcissism and the active pursuit of short-term mating strategies (e.g., unrestricted sociosexuality, marital infidelity, mate poaching). Nearly all of these investigations have relied solely on samples from Western cultures. In the current study, responses from a cross-cultural survey of 30,470 people across 53 nations spanning 11 world regions (North America, Central/South America, Northern Europe, Western Europe, Eastern Europe, Southern Europe, Middle East, Africa, Oceania, Southeast Asia, and East Asia) were used to evaluate whether narcissism (as measured by the Narcissistic Personality Inventory; NPI) was universally associated with short-term mating. Results revealed narcissism scores (including two broad factors and seven traditional facets as measured by the NPI) were functionally equivalent across cultures, reliably associating with key sexual outcomes (e.g., more active pursuit of short-term mating, intimate partner violence, and sexual aggression) and sex-related personality traits (e.g., higher extraversion and openness to experience). Whereas some features of personality (e.g., subjective well-being) were universally associated with socially adaptive facets of Narcissism (e.g., self-sufficiency), most indicators of short-term mating (e.g., unrestricted sociosexuality and marital infidelity) were universally associated with the socially maladaptive facets of narcissism (e.g., exploitativeness). Discussion addresses limitations of these cross-culturally universal findings and presents suggestions for future research into revealing the precise psychological features of narcissism that facilitate the strategic pursuit of short-term mating.Estudios previos, en primer lugar a través de las muestras de culturas occidentales, han documentado asociaciones sistemáticas del narcisismo subclínico con múltiples indicadores de estrategias del emparejamiento a corto plazo (p. ej. sociosexualidad ilimitada, infidelidad, caza de pareja). En este estudio se han usado respuestas de la encuesta transcultural de 30.470 personas de 53 naciones de 11 regiones mundiales (América del Norte, América del Sur/América Central, Europa del Norte, Europa del Oeste, Europa del Este, Europa del Sur, Oriente Próximo, África, Asia del Sur/Sudoeste de Asia, Asia del Este y Oceanía) para evaluar si el narcisismo (medido por el Inventario de Personalidad Narcisista; NPI) se asocia panuniversalmente con los indicadores del emparejamiento a corto plazo, tanto en la dirección, como en la intensidad. Los resultados sugieren que el narcisismo (incluidos muchos aspectos suyos medidos por el NPI) tiene las mismas asociaciones básicas con los rasgos de personalidad relacionados con el sexo (p. ej. extraversión alta) y con los resultados sexuales claves (p. ej. búsqueda más activa de las estrategias del emparejamiento a corto plazo) a través de las 11 mayores regiones mundiales del PDSI 2. La discusión se enfoca en las implicaciones y limitaciones del estudio actual

    Effect of remote ischaemic conditioning on clinical outcomes in patients with acute myocardial infarction (CONDI-2/ERIC-PPCI): a single-blind randomised controlled trial.

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    BACKGROUND: Remote ischaemic conditioning with transient ischaemia and reperfusion applied to the arm has been shown to reduce myocardial infarct size in patients with ST-elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PPCI). We investigated whether remote ischaemic conditioning could reduce the incidence of cardiac death and hospitalisation for heart failure at 12 months. METHODS: We did an international investigator-initiated, prospective, single-blind, randomised controlled trial (CONDI-2/ERIC-PPCI) at 33 centres across the UK, Denmark, Spain, and Serbia. Patients (age >18 years) with suspected STEMI and who were eligible for PPCI were randomly allocated (1:1, stratified by centre with a permuted block method) to receive standard treatment (including a sham simulated remote ischaemic conditioning intervention at UK sites only) or remote ischaemic conditioning treatment (intermittent ischaemia and reperfusion applied to the arm through four cycles of 5-min inflation and 5-min deflation of an automated cuff device) before PPCI. Investigators responsible for data collection and outcome assessment were masked to treatment allocation. The primary combined endpoint was cardiac death or hospitalisation for heart failure at 12 months in the intention-to-treat population. This trial is registered with ClinicalTrials.gov (NCT02342522) and is completed. FINDINGS: Between Nov 6, 2013, and March 31, 2018, 5401 patients were randomly allocated to either the control group (n=2701) or the remote ischaemic conditioning group (n=2700). After exclusion of patients upon hospital arrival or loss to follow-up, 2569 patients in the control group and 2546 in the intervention group were included in the intention-to-treat analysis. At 12 months post-PPCI, the Kaplan-Meier-estimated frequencies of cardiac death or hospitalisation for heart failure (the primary endpoint) were 220 (8·6%) patients in the control group and 239 (9·4%) in the remote ischaemic conditioning group (hazard ratio 1·10 [95% CI 0·91-1·32], p=0·32 for intervention versus control). No important unexpected adverse events or side effects of remote ischaemic conditioning were observed. INTERPRETATION: Remote ischaemic conditioning does not improve clinical outcomes (cardiac death or hospitalisation for heart failure) at 12 months in patients with STEMI undergoing PPCI. FUNDING: British Heart Foundation, University College London Hospitals/University College London Biomedical Research Centre, Danish Innovation Foundation, Novo Nordisk Foundation, TrygFonden

    An investigation of strategies to teach word processing skills to young adults with intellectual disabilities

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    This research project had two aims. The first aim was to develop guidelines to assist in the selection and evaluation of computer software packages for use in a literacy program for young adults with intellectual disabilities. The second aim was to develop, implement, and evaluate strategies to enable learners with intellectual disabilities to work independently with a word processing program. Three studies were undertaken to achieve these aims. The first was the preliminary study, the second was the main study, and the third study was an extension of the main study to a larger classroom context. The preliminary study was conducted to develop guidelines that could be used to gather information about three commercial educational software programs that were available at the time and were being promoted as effective tools in the teaching of literacy. A range of characteristics and qualities of effective programs was identified from a review of the literature and these findings were used to develop checklists to assess available software. Findings from the preliminary study revealed a need to further explore the learners needs and skills when using software packages such as Microsoft Word 98 in classroom settings. These findings formed the basis for the main study. The aim of the main study was to develop, implement, and evaluate teaching strategies to enable students with intellectual disabilities to work independently with word processing using Microsoft Word 98. Action research was adopted as the research design for the main study. The participants in the main study were 11 young adults with intellectual disabilities ranging in age from 18 to 25 years. In the Initial Reconnaissance Phase, a combination of formal standardised assessments, informal researcher developed instruments, and informal assessments were used to collect data about the participants computer skills, comprehension skills, vocabulary, interests, attitudes and behaviours. Using the findings from these assessments, a General Plan was developed to teach a specific computer skill - saving and retrieving documents from a specific folder. A pre-test was administered prior to the commencement of the teaching sessions and then readministered as a post-test at the conclusion of the sessions. The participants were then observed in their regular classroom to determine if the skill had been retained after a 10-week period. The findings from the post assessments showed positive results for all participants in the study. The study was then extended to a larger group of learners in a classroom setting. The classroom study included all learners in the group (n=10). The General Plan was revised but as it proved to be successful in its original format, few changes were made. In the classroom study, the post-tests revealed that seven participants were able to save and retrieve documents independently from a specific folder, and three participants were not able to save independently. The study indicated a range of strategies that could be used to help the remainder of the learners build towards gaining the targeted computer skills. The results from this investigation add to the current body of knowledge about software evaluation and teaching strategies that can be used to enhance the computer skills of young adults with intellectual disabilities. These findings have important implications for the design of literacy programs and how technology can be used as a teaching tool to create a richer teaching environment

    A dialogic approach to working inclusively in a Research Reference Committee

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    This paper reports the use of a dialogic approach to working inclusively with two young people with intellectual disability as part of a Research Reference Committee for a project that examined how adults with intellectual disability and their families plan for their future. The paper begins with an overview of the role of the Research Reference Committee written by the research team to provide the context for reporting. We then discuss and reflect on how we used mediated talk to working with the young people with intellectual disability to develop strategies for enabling them to actively contribute to the reference committee. The third section of the paper was co‐written with authors 3 and 4. The structure follows their decisions about how they wanted to write this section in ways that allowed them to tell their stories of participation as narratives, using their own words. In the discussion, we acknowledge the challenges of co‐authorship and consider the benefits of using an iterative dialogical approach to enable the active participation of these young people in a reference committee, and as a method of co‐authoring that allows a broader dissemination the voices of the young people with intellectual disability in research outputs
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