131 research outputs found

    La valeur économique totale de la forêt méditerranéenne française.

    Get PDF
    À partir d'une importante collecte de données, cet article fournit une analyse étendue et une comparaison des valeurs économiques liées aux forêts françaises et méditerranéennes, incluant non seulement les valeurs aisément et traditionnellement mesurées comme la production de bois, mais aussi les biens publics et les externalités qu'elles engendrent. Ces valeurs estimées, placées dans le contexte institutionnel et politique qui régit la gestion forestière, peuvent contribuer à une meilleure prise en compte des différents enjeux et défis auxquels font face les forêts, dessinant de nouvelles approches de politique publique permettant d'accroître la provision de biens publics tout en réduisant les effets négatifs concomitants

    Branchpoint translocation by fork remodelers as a general mechanism of R-loop removal.

    Get PDF
    Co-transcriptional R loops arise from stalling of RNA polymerase, leading to the formation of stable DNA:RNA hybrids. Unresolved R loops promote genome instability but are counteracted by helicases and nucleases. Here, we show that branchpoint translocases are a third class of R-loop-displacing enzyme in vitro. In cells, deficiency in the Fanconi-anemia-associated branchpoint translocase FANCM causes R-loop accumulation, particularly after treatment with DNA:RNA-hybrid-stabilizing agents. This correlates with FANCM localization at R-loop-prone regions of the genome. Moreover, other branchpoint translocases associated with human disease, such as SMARCAL1 and ZRANB3, and those from lower organisms can also remove R loops in vitro. Branchpoint translocases are more potent than helicases in resolving R loops, indicating their evolutionary important role in R-loop suppression. In human cells, FANCM, SMARCAL1, and ZRANB3 depletion causes additive effects on R-loop accumulation and DNA damage. Our work reveals a mechanistic basis for R-loop displacement that is linked to genome stability

    Predictors of COVID-19 vaccine hesitancy in the UK household longitudinal study

    Get PDF
    Vaccine hesitancy could undermine efforts to control COVID-19. We investigated the prevalence of COVID-19 vaccine hesitancy in the UK and identified vaccine hesitant subgroups. The ‘Understanding Society’ COVID-19 survey asked participants (n = 12,035) their likelihood of vaccine uptake and reason for hesitancy. Cross-sectional analysis assessed vaccine hesitancy prevalence and logistic regression calculated odds ratios. Overall vaccine hesitancy was low (18% unlikely/very unlikely). Vaccine hesitancy was higher in women (21.0% vs 14.7%), younger age groups (26.5% in 16–24 year olds vs 4.5% in 75 + ) and those with lower education levels (18.6% no qualifications vs 13.2% degree qualified). Vaccine hesitancy was high in Black (71.8%) and Pakistani/Bangladeshi (42.3%) ethnic groups. Odds ratios for vaccine hesitancy were 13.42 (95% CI:6.86, 26.24) in Black and 2.54 (95% CI:1.19, 5.44) in Pakistani/Bangladeshi groups (compared to White British/Irish) and 3.54 (95% CI:2.06, 6.09) for people with no qualifications versus degree. Urgent action to address hesitancy is needed for some but not all ethnic minority groups

    Microdevices for extensional rheometry of low viscosity elastic liquids : a review

    Get PDF
    Extensional flows and the underlying stability/instability mechanisms are of extreme relevance to the efficient operation of inkjet printing, coating processes and drug delivery systems, as well as for the generation of micro droplets. The development of an extensional rheometer to characterize the extensional properties of low viscosity fluids has therefore stimulated great interest of researchers, particularly in the last decade. Microfluidics has proven to be an extraordinary working platform and different configurations of potential extensional microrheometers have been proposed. In this review, we present an overview of several successful designs, together with a critical assessment of their capabilities and limitations

    Unconventional Ubiquitin Recognition by the Ubiquitin-Binding Motif within the Y-Family DNA Polymerases ι and Rev1

    Get PDF
    Translesion synthesis is an essential cell survival strategy to promote replication after DNA damage. The accumulation of Y family polymerases (pol) ι and Rev1 at the stalled replication machinery is mediated by the ubiquitin-binding motifs (UBMs) of the polymerases and enhanced by PCNA monoubiquitination. We report the solution structures of the C-terminal UBM of human pol ι and its complex with ubiquitin. Distinct from other ubiquitin-binding domains, the UBM binds to the hydrophobic surface of ubiquitin centered at L8. Accordingly, mutation of L8A, but not I44A, of ubiquitin abolishes UBM binding. Human pol ι contains two functional UBMs, both contributing to replication foci formation. In contrast, only the second UBM of Saccharomyces cerevisiae Rev1 binds to ubiquitin and is essential for Rev1-dependent cell survival and mutagenesis. Point mutations disrupting the UBM-ubiquitin interaction also impair the accumulation of pol ι in replication foci and Rev1-mediated DNA damage tolerance in vivo.National Institute of General Medical Sciences (U.S.) (Grant GM-079376)American Cancer Society. Research ProfessorshipNational Institute of Environmental Health Sciences (Grant P30 ES-002109

    Loss of ubiquitin E2 Ube2w rescues hypersensitivity of Rnf4 mutant cells to DNA damage

    Get PDF
    SUMO and ubiquitin play important roles in the response of cells to DNA damage. These pathways are linked by the SUMO Targeted ubiquitin Ligase Rnf4 that catalyses transfer of ubiquitin from a ubiquitin loaded E2 conjugating enzyme to a polySUMO modified substrate. Rnf4 can functionally interact with multiple E2s, including Ube2w, in vitro. Chicken cells lacking Rnf4 are hypersensitive to hyroxyurea, DNA alkylating drugs and DNA crosslinking agents, but this sensitivity is suppressed by simultaneous depletion of Ube2w. Cells depleted of Ube2w alone are not hypersensitive to the same DNA damaging agents. Similar results were also obtained in human cells. These data indicate that Ube2w does not have an essential role in the DNA damage response, but is deleterious in the absence of Rnf4. Thus, although Rnf4 and Ube2w functionally interact in vitro, our genetic experiments indicate that in response to DNA damage Ube2w and Rnf4 function in distinct pathways

    The Fanconi Anemia Core Complex Is Dispensable during Somatic Hypermutation and Class Switch Recombination

    Get PDF
    To generate high affinity antibodies during an immune response, B cells undergo somatic hypermutation (SHM) of their immunoglobulin genes. Error-prone translesion synthesis (TLS) DNA polymerases have been reported to be responsible for all mutations at template A/T and at least a fraction of G/C transversions. In contrast to A/T mutations which depend on PCNA ubiquitination, it remains unclear how G/C transversions are regulated during SHM. Several lines of evidence indicate a mechanistic link between the Fanconi Anemia (FA) pathway and TLS. To investigate the contribution of the FA pathway in SHM we analyzed FancG-deficient B cells. B cells deficient for FancG, an essential member of the FA core complex, were hypersensitive to treatment with cross-linking agents. However, the frequencies and nucleotide exchange spectra of SHM remained comparable between wild-type and FancG-deficient B cells. These data indicate that the FA pathway is not involved in regulating the outcome of SHM in mammals. In addition, the FA pathway appears dispensable for class switch recombination

    Mental health and well-being during the second wave of COVID-19: longitudinal analyses of the UK COVID-19 Mental Health and Wellbeing study (UK COVID-MH)

    Get PDF
    Background Waves 1 to 3 (March 2020 to May 2020) of the UK COVID-19 Mental Health and Wellbeing study suggested an improvement in some indicators of mental health across the first 6 weeks of the UK lockdown; however, suicidal ideation increased. Aims To report the prevalence of mental health and well-being of adults in the UK from March/April 2020 to February 2021. Method Quota sampling was employed at wave 1 (March/April 2020), and online surveys were conducted at seven time points. Primary analyses cover waves 4 (May/June 2020), 5 (July/August 2020), 6 (October 2020) and 7 (February 2021), including a period of increased restrictions in the UK. Mental health indicators were suicidal ideation, self-harm, suicide attempt, depression, anxiety, defeat, entrapment, loneliness and well-being. Results A total of 2691 (87.5% of wave 1) individuals participated in at least one survey between waves 4 and 7. Depressive symptoms and loneliness increased from October 2020 to February 2021. Defeat and entrapment increased from July/August 2020 to October 2020, and remained elevated in February 2021. Well-being decreased from July/August 2020 to October 2020. Anxiety symptoms and suicidal ideation did not change. Young adults, women, those who were socially disadvantaged and those with a pre-existing mental health condition reported worse mental health. Conclusions The mental health and well-being of the UK population deteriorated from July/August 2020 to October 2020 and February 2021, which coincided with the second wave of COVID-19. Suicidal thoughts did not decrease significantly, suggesting a need for continued vigilance as we recover from the pandemic

    SF3B1 hotspot mutations confer sensitivity to PARP inhibition by eliciting a defective replication stress response.

    Get PDF
    SF3B1 hotspot mutations are associated with a poor prognosis in several tumor types and lead to global disruption of canonical splicing. Through synthetic lethal drug screens, we identify that SF3B1 mutant (SF3B1MUT) cells are selectively sensitive to poly (ADP-ribose) polymerase inhibitors (PARPi), independent of hotspot mutation and tumor site. SF3B1MUT cells display a defective response to PARPi-induced replication stress that occurs via downregulation of the cyclin-dependent kinase 2 interacting protein (CINP), leading to increased replication fork origin firing and loss of phosphorylated CHK1 (pCHK1; S317) induction. This results in subsequent failure to resolve DNA replication intermediates and G2/M cell cycle arrest. These defects are rescued through CINP overexpression, or further targeted by a combination of ataxia-telangiectasia mutated and PARP inhibition. In vivo, PARPi produce profound antitumor effects in multiple SF3B1MUT cancer models and eliminate distant metastases. These data provide the rationale for testing the clinical efficacy of PARPi in a biomarker-driven, homologous recombination proficient, patient population
    corecore