Dchs1-Fat4 regulation of osteogenic differentiation in mouse.

In human, mutations of the protocadherins FAT4 and DCHS1 result in Van Maldergem syndrome, which is characterised, in part, by craniofacial abnormalities. Here, we analyse the role of Dchs1-Fat4 signalling during osteoblast differentiation in mouse. We show that Fat4 and Dchs1 mutants mimic the craniofacial phenotype of the human syndrome and that Dchs1-Fat4 signalling is essential for osteoblast differentiation. In Dchs1/Fat4 mutants, proliferation of osteoprogenitors is increased and osteoblast differentiation is delayed. We show that loss of Dchs1-Fat4 signalling is linked to increased Yap-Tead activity and that Yap is expressed and required for proliferation in osteoprogenitors. In contrast, Taz is expressed in more-committed Runx2-expressing osteoblasts, Taz does not regulate osteoblast proliferation and Taz-Tead activity is unaffected in Dchs1/Fat4 mutants. Finally, we show that Yap and Taz differentially regulate the transcriptional activity of Runx2, and that the activity of Yap-Runx2 and Taz-Runx2 complexes is altered in Dchs1/Fat4 mutant osteoblasts. In conclusion, these data identify Dchs1-Fat4 as a signalling pathway in osteoblast differentiation, reveal its crucial role within the early Runx2 progenitors, and identify distinct requirements for Yap and Taz during osteoblast differentiation.

Fundamental challenges in assessing the impact of research infrastructure.

Clinical research infrastructure is one of the unsung heroes of the scientific response to the current COVID-19 pandemic. The extensive, long-term funding into research support structures, skilled people, and technology allowed the United Kingdom research response to move off the starting blocks at pace by utilizing pre-existing platforms. The increasing focus from funders on evaluating the outcomes and impact of research infrastructure investment requires both a reframing and progression of the current models in order to address the contribution of the underlying support infrastructure. The majority of current evaluation/outcome models focus on a "pipeline" approach using a methodology which follows the traditional research funding route with the addition of quantitative metrics. These models fail to embrace the complexity caused by the interplay of previous investment, the coalescing of project outputs from different funders, the underlying infrastructure investment, and the parallel development across different parts of the system. Research infrastructure is the underpinning foundation of a project-driven research system and requires long-term, sustained funding and capital investment to maintain scientific and technological expertise. Therefore, the short-term focus on quantitative metrics that are easy to collect and interpret and that can be assessed in a roughly 5-year funding cycle needs to be addressed. The significant level of investment in research infrastructure necessitates investment to develop bespoke methodologies that develop fit-for-purpose, longer-term/continual approach(es) to evaluation. Real-world research should reflect real-world evaluation and allow for the accrual of a narrative of value indicators that build a picture of the contribution of infrastructure to research outcomes. The linear approach is not fit for purpose, the research endeavour is a complex, twisted road, and the evaluation approach needs to embrace this complexity through the development of realist approaches and the rapidly evolving data ecosystem. This paper sets out methodological challenges and considers the need to develop bespoke methodological approaches to allow a richer assessment of impact, contribution, attribution, and evaluation of research infrastructure. This paper is the beginning of a conversation that invites the community to "take up the mantle" and tackle the complexity of real-world research translation and evaluation.

Fat4-Dchs1 signalling controls cell proliferation in developing vertebrae.

The protocadherins Fat4 and Dchs1 act as a receptor-ligand pair to regulate many developmental processes in mice and humans, including development of the vertebrae. Based on conservation of function between Drosophila and mammals, Fat4-Dchs1 signalling has been proposed to regulate planar cell polarity (PCP) and activity of the Hippo effectors Yap and Taz, which regulate cell proliferation, survival and differentiation. There is strong evidence for Fat regulation of PCP in mammals but the link with the Hippo pathway is unclear. In Fat4(-/-) and Dchs1(-/-) mice, many vertebrae are split along the midline and fused across the anterior-posterior axis, suggesting that these defects might arise due to altered cell polarity and/or changes in cell proliferation/differentiation. We show that the somite and sclerotome are specified appropriately, the transcriptional network that drives early chondrogenesis is intact, and that cell polarity within the sclerotome is unperturbed. We find that the key defect in Fat4 and Dchs1 mutant mice is decreased proliferation in the early sclerotome. This results in fewer chondrogenic cells within the developing vertebral body, which fail to condense appropriately along the midline. Analysis of Fat4;Yap and Fat4;Taz double mutants, and expression of their transcriptional target Ctgf, indicates that Fat4-Dchs1 regulates vertebral development independently of Yap and Taz. Thus, we have identified a new pathway crucial for the development of the vertebrae and our data indicate that novel mechanisms of Fat4-Dchs1 signalling have evolved to control cell proliferation within the developing vertebrae.

Characterization of a Dchs1 mutant mouse reveals requirements for Dchs1-Fat4 signaling during mammalian development.

The Drosophila Dachsous and Fat proteins function as ligand and receptor, respectively, for an intercellular signaling pathway that regulates Hippo signaling and planar cell polarity. Although gene-targeted mutations in two mammalian Fat genes have been described, whether mammals have a Fat signaling pathway equivalent to that in Drosophila, and what its biological functions might be, have remained unclear. Here, we describe a gene-targeted mutation in a murine Dachsous homolog, Dchs1. Analysis of the phenotypes of Dchs1 mutant mice and comparisons with Fat4 mutant mice identify requirements for these genes in multiple organs, including the ear, kidney, skeleton, intestine, heart and lung. Dchs1 and Fat4 single mutants and Dchs1 Fat4 double mutants have similar phenotypes throughout the body. In some cases, these phenotypes suggest that Dchs1-Fat4 signaling influences planar cell polarity. In addition to the appearance of cysts in newborn kidneys, we also identify and characterize a requirement for Dchs1 and Fat4 in growth, branching and cell survival during early kidney development. Dchs1 and Fat4 are predominantly expressed in mesenchymal cells in multiple organs, and mutation of either gene increases protein staining for the other. Our analysis implies that Dchs1 and Fat4 function as a ligand-receptor pair during murine development, and identifies novel requirements for Dchs1-Fat4 signaling in multiple organs.

Machine Learning and Gene Editing at the Helm of a Societal Evolution.

The integration of artificial intelligence (AI) and biotechnology, whilst in its infancy, presents significant opportunities and risks, and proactive policy is needed to manage these emerging technologies. Whilst AI continues to have significant and broad impact, its relevance and complexity magnify when integrated with other emerging technologies. The confluence of Machine Learning (ML), a subset of AI, with gene editing (GE) in particular can foster substantial benefits as well as daunting risks that range from ethics to national security. These complex technologies have implications for multiple sectors, ranging from agriculture and medicine to economic competition and national security. Consideration of technology advancements and policies in different geographic regions, and involvement of multiple organisations further confound this complexity. As the impact of ML and GE expands, forward looking policy is needed to mitigate risks and leverage opportunities. Thus, this study explores the technological and policy implications of the intersection of ML and GE, with a focus on the United States (US), the United Kingdom (UK), China, and the European Union (EU). Analysis of technical and policy developments over time and an assessment of their current state have informed policy recommendations that can help manage beneficial use of technology advancements and their convergence, which can be applied to other sectors. This study is intended for policymakers to prompt reflection on how to best approach the convergence of the two technologies. Technical practitioners may also find it valuable as a resource to consider the type of information and policy stakeholders engage with.

Physical properties of the low-cost CZTS absorber layer deposited by spin-coating: effect of the copper concentration associated with SCAPS-1D simulation.

Five samples of copper zinc tin sulfide (CZTS) thin films were deposited by a spin-coating technique at various copper concentrations ranging from 0.5 M to 2.5 M in steps of 0.5 M, in order to improve their stability, efficiency, performance, and reduce the production costs. The XRD patterns showed the existence of the three main characteristic peaks of CZTS (112), (220), and (312), which indicated the formation of the kesterite structure of CZTS. The gap energy of the thin films was calculated based on the derivation method using the absorbance data, and the values obtained varied from 1.46-1.58 eV for 0.5, 1, 1.5, 2, and 2.5 M copper molarity, respectively. Hall effect measurements were used to determine conductivity, which in turn increased with the concentration of copper in the films. The characterization results showed that the sample C3, which represents the 1.5 M copper concentration, exhibited higher crystallinity and better optical and electrical performance than the others. Finally, a theoretical efficiency of 11.6% was obtained when simulating the solar cell using the CZTS thin film (CZTS/ZnS/S:ZnO) in the SCAPS-1D simulation program using the parameters obtained in this study. Under the adopted synthesis conditions, the theoretical simulation corroborated the experimental findings, thus confirming that the synthesized material is a promising candidate for solar cell applications as an absorber layer.

Setting national research priorities for difficult-to-treat depression in the UK between 2021-2026.

Background: Difficult-to-treat depression (DTD) presents a substantial health care challenge, with around one-third of people diagnosed with a depressive episode in the UK finding that their symptoms persist following treatment. This study aimed to identify priority research questions (RQs) that could inform the development of new and improved treatments, interventions, and support for people with DTD. Methods: Using an adapted Child Health and Nutrition Research Initiative (CHNRI) method, this national prioritisation exercise engaged 60 leading researchers and health care professionals in the UK, as well as 25 wider stakeholders with relevant lived experience to produce a ranked list of priority RQs in DTD. The final list of 99 distinct RQs was independently scored by 42 individuals against a list of five criteria: answerability, effectiveness, impact on health, deliverability, and equity. Results: Highly ranked RQs covered a range of novel and existing treatments. The three highest scoring RQs included evaluation of psychological and pharmacological therapies (eg, behavioural activation, and augmentation therapies), as well as social interventions to reduce loneliness or increase support for people with DTD. Conclusions: This exercise identified and prioritised 99 RQs that could inform future research and funding decisions over the next five years. The results of this research could improve treatment and support for people affected by DTD. It also serves as an example of ways in which the CHNRI method can be adapted in a collaborative manner to provide a more active role for patients, carers, and health care professionals.

Attitudes to Cardiopulmonary Resuscitation and Defibrillator Use: A Survey of UK Adults in 2017.

Background Bystander cardiopulmonary resuscitation ( CPR ) and public access defibrillator ( PAD ) use can save the lives of people who experience out-of-hospital cardiac arrest. Little is known about the proportions of UK adults trained, their characteristics and willingness to act if witnessing an out-of-hospital cardiac arrest, or the public's knowledge regarding where the nearest PAD is located. Methods and Results An online survey was administered by YouGov to a nonprobabilistic purposive sample of UK adults, achieving 2084 participants, from a panel that was matched to be representative of the population. We used descriptive statistics and multivariate logistic regression modeling for analysis. Almost 52% were women, 61% were aged <55 years, and 19% had witnessed an out-of-hospital cardiac arrest. Proportions ever trained were 57% in chest-compression-only CPR, 59% in CPR , and 19.4% in PAD use. Most with training in any resuscitation technique had trained at work (54.7%). Compared with people not trained, those trained in PAD use said they were more likely to use one (odds ratio: 2.61), and those trained in CPR or chest-compression-only CPR were more likely to perform it (odds ratio: 5.39). Characteristics associated with being trained in any resuscitation technique included youth, female sex, higher social grade, and full-time employment. Conclusions In the United Kingdom, training makes a difference in people's willingness to act in the event of a cardiac arrest. Although there is considerable opportunity to increase the proportion of the general population trained in CPR , consideration should be also given to encouraging training in PAD use and targeting training for those who are older or from lower social grades.

Regulation of neuronal migration by Dchs1-Fat4 planar cell polarity.

Planar cell polarity (PCP) describes the polarization of cell structures and behaviors within the plane of a tissue. PCP is essential for the generation of tissue architecture during embryogenesis and for postnatal growth and tissue repair, yet how it is oriented to coordinate cell polarity remains poorly understood [1]. In Drosophila, PCP is mediated via the Frizzled-Flamingo (Fz-PCP) and Dachsous-Fat (Fat-PCP) pathways [1-3]. Fz-PCP is conserved in vertebrates, but an understanding in vertebrates of whether and how Fat-PCP polarizes cells, and its relationship to Fz-PCP signaling, is lacking. Mutations in human FAT4 and DCHS1, key components of Fat-PCP signaling, cause Van Maldergem syndrome, characterized by severe neuronal abnormalities indicative of altered neuronal migration [4]. Here, we investigate the role and mechanisms of Fat-PCP during neuronal migration using the murine facial branchiomotor (FBM) neurons as a model. We find that Fat4 and Dchs1 are expressed in complementary gradients and are required for the collective tangential migration of FBM neurons and for their PCP. Fat4 and Dchs1 are required intrinsically within the FBM neurons and extrinsically within the neuroepithelium. Remarkably, Fat-PCP and Fz-PCP regulate FBM neuron migration along orthogonal axes. Disruption of the Dchs1 gradients by mosaic inactivation of Dchs1 alters FBM neuron polarity and migration. This study implies that PCP in vertebrates can be regulated via gradients of Fat4 and Dchs1 expression, which establish intracellular polarity across FBM cells during their migration. Our results also identify Fat-PCP as a novel neuronal guidance system and reveal that Fat-PCP and Fz-PCP can act along orthogonal axes.