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OBJECTIVE: Childhood vaccine uptake in the United Kingdom (UK) is sub-optimal leading to outbreaks of preventable diseases. We aimed to explore UK parents' perspectives on why some children are unvaccinated or vaccinated late. METHODS: We undertook a mixed-methods, co-production study involving a survey using a questionnaire followed by focus groups. We partnered with The Mosaic Community Trust (Mosaic) who are based in a more deprived, ethnically diverse, low vaccine uptake area of London. Targeted recruitment to complete the questionnaire (either on paper or online) was done through Mosaic, community networks and social media promotion. We collected demographic data alongside parents' views on routine childhood vaccination, their vaccine decisions, and experiences of accessing childhood vaccine appointments We report descriptive findings from the questionnaire and thematic analysis of free-text questionnaire answers and focus groups guided by the COM-B model of Capability, Opportunity, and Motivation. RESULTS: Between June-October 2022, 518 parents were surveyed of whom 25% (n = 130), were from ethnic minorities (13%, n = 68-unknown ethnicity). In 2023 we held four focus groups with 22 parents (10 from ethnic minorities). Only 15% (n = 78) parents had delayed or refused a vaccine for their child. A quarter of parents felt they had not been given enough information nor an opportunity to ask questions before their children's vaccinations. Inconsistent reminders and difficulties booking or attending appointments impacted vaccine uptake with negative experiences influencing future vaccine decisions. Parents had mixed views on vaccinations being given in different locations and wanted trusted health professionals to vaccinate their children. CONCLUSION: To reverse declining vaccine uptake and prevent future outbreaks it needs to be easier for UK parents to speak to health professionals to answer their childhood vaccine questions, alongside simplified booking systems and easier access to routine childhood vaccine appointments.
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This manuscript investigates the efficient synthesis of copper zinc tin sulfide (CZTS) nanoparticles for CZTS thin film solar cell applications with a primary focus on environmental sustainability. Underpinning the investigation is an initial life-cycle assessment (LCA) analysis. This LCA analysis is conducted to evaluate the environmental impact of different synthesis volumes, providing crucial insights into the sustainability of the synthesis process by considering the flows of material and energy associated with the process. Life-cycle assessment results demonstrate that significant reductions to the environmental impact can be made by increasing the synthesis volume of CZTS nanoparticle ink. Using a 5-fold increase in volume can reduce all 11 investigated environmental impacts by up to 35.6%, six of these impacts demonstrating reductions >10% and the amount of global warming potential is reduced by 21.4%. Motivated by the LCA results, COMSOL simulations are employed to understand the fluid flow patterns in large-scale fabrication. Various sizes and speeds of stirrer bars are investigated in these simulations, and it is determined that a 50 mm stir bar at 200 rpm represents the optimal configuration for the synthesis process in a 500 mL flask. Subsequently, large-batch CZTS nanoparticle inks are synthesized using these parameters and compared to small-batch samples. The light absorbers are characterized using Raman spectroscopy and X-ray diffraction, confirming favorable properties with close-to-ideal elemental ratios in large-batch synthesis. Finally, solar cell devices fabricated utilizing CZTSSe absorbers from the large volume synthesis process demonstrate comparable performance to those fabricated using small-batch synthesis, with uniform power conversion efficiencies of around 5% across the substrate. This study highlights the potential of large-volume CZTS nanoparticle synthesis for efficient and environmentally friendly CZTS solar cell fabrication, contributing to the advancement of sustainable renewable energy technologies.
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Shigellosis is an enteric infection that transmits through the faecal-oral route, which can occur during sex between men who have sex with men (MSM). Between 2009 and 2014, an epidemic of sexually transmissible Shigella flexneri 3a occurred in England that subsequently declined. However, from 2019 to 2021, despite SARS-CoV-2 restrictions, S. flexneri 3a continued to re-emerge. We explored possible drivers of re-emergence by comparing host demography and pathogen genomics. Cases were primarily among 35-64 year old men in London. Genomic analyses of 502 bacterial isolates showed that the majority (58%) of re-emerging MSM strains were a clonal replacement of the original, with reduced antimicrobial resistance, conservation of plasmid col156_1, and two SNPs with 19 predicted effects. The absence of major changes in the pathogen or host demographics suggest that other factors may have driven the re-emergence of S. flexneri 3a and highlight the need for further work in the area.
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The natural product ambergris is only found rarely on beaches, as jetsam. Even more scarce, or even absent, are accounts of flotsam ambergris. Here, we report the chemical analysis of a rare, large piece (>100kg) of flotsam found in the Atlantic in 2019. About 95% of subsamples from the outside of the coprolith was soluble in dichloromethane. Of this, FTIR spectroscopy, APCI-MS and GC-MS indicated the presence of ambrein. Radiocarbon dating indicated that the sample was post 1950s in age. The 13C/12C isotope ratio (-22.5 ) was typical of those reported to date for whale 'body' ambergris. Metals of ambergris have hardly been reported previously. The distribution found here for the flotsam, was dominated by copper and zinc, which is similar to that of several squid species. This is also consistent with the presence of squid beaks in the coprolith. Squid are a major prey species of sperm whales.
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Genome-Wide Association Studies (GWAS) over-represent European ancestries, neglecting all other ancestry groups and low-income nations. Consequently, polygenic risk scores (PRS) more accurately predict complex traits in Europeans than African Ancestries groups. Very few studies have looked at the transferability of European-derived PRS for behavioural and mental health phenotypes to Africans. We assessed the comparative accuracy of depression PRS trained on European and African Ancestries GWAS studies to predict major depressive disorder (MDD) and related traits in African ancestry participants from the UK Biobank. UK Biobank participants were selected based on Principal component analysis clustering with an African genetic similarity reference population, MDD was assessed with the Composite International Diagnostic Interview (CIDI). PRS were computed using PRSice2 software using either European or African Ancestries GWAS summary statistics. PRS trained on European ancestry samples (246,363 cases) predicted case control status in Africans of the UK Biobank with similar accuracies (R2 = 2%, ß = 0.32, empirical p-value = 0.002) to PRS trained on far much smaller samples of African Ancestries participants from 23andMe, Inc. (5045 cases, R² = 1.8%, ß = 0.28, empirical p-value = 0.008). This suggests that prediction of MDD status from Africans to Africans had greater efficiency relative to discovery sample size than prediction of MDD from Europeans to Africans. Prediction of MDD status in African UK Biobank participants using GWAS findings of likely causal risk factors from European ancestries was non-significant. GWAS of MDD in European ancestries are inefficient for improving polygenic prediction in African samples; urgent MDD studies in Africa are needed.
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Aging is associated with a significant decline in aerobic capacity assessed by maximal exercise oxygen consumption (VÌo2max). The relative contributions of the specific VÌo2 components driving this decline, namely cardiac output (CO) and arteriovenous oxygen difference (A - V)O2, remain unclear. We examined this issue by analyzing data from 99 community-dwelling participants (baseline age: 21-96 yr old; average follow-up: 12.6 yr old) from the Baltimore Longitudinal Study of Aging, free of clinical cardiovascular disease. VÌo2peak, a surrogate of VÌo2max, was used to assess aerobic capacity during upright cycle ergometry. Peak exercise left ventricular volumes, heart rate, and CO were estimated using repeated gated cardiac blood pool scans. The Fick equation was used to calculate (A - V)O2diff,peak from COpeak and VÌo2peak. In unadjusted models, VÌo2peak, (A - V)O2diff,peak, and COpeak declined longitudinally over time at steady rates with advancing age. In multiple linear regression models adjusting for baseline values and peak workload, however, steeper declines in VÌo2peak and (A - V)O2diff,peak were observed with advanced entry age but not in COpeak. The association between the declines in VÌo2peak and (A - V)O2diff,peak was stronger among those ≥50 yr old compared with their younger counterparts, but the difference between the two age groups did not reach statistical significance. These findings suggest that age-associated impairment of peripheral oxygen utilization during maximal exercise poses a stronger limitation on peak VÌo2 than that of CO. Future studies examining interventions targeting the structure and function of peripheral muscles and their vasculature to mitigate age-associated declines in (A - V)O2diff are warranted.NEW & NOTEWORTHY The age-associated decline in aerobic exercise performance over an average of 13 yr in community-dwelling healthy individuals is more closely associated with decreased peripheral oxygen utilization rather than decreased cardiac output. This association was more evident in older than younger individuals. These findings suggest that future studies with larger samples examine whether these associations vary across the age range and whether the decline in cardiac output plays a greater role earlier in life. In addition, studies focused on determinants of peripheral oxygen uptake by exercising muscle may guide the selection of preventive strategies designed to maintain physical fitness with advancing age.
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Envejecimiento , Gasto Cardíaco , Consumo de Oxígeno , Humanos , Anciano , Persona de Mediana Edad , Masculino , Consumo de Oxígeno/fisiología , Femenino , Adulto , Envejecimiento/fisiología , Envejecimiento/metabolismo , Estudios Longitudinales , Anciano de 80 o más Años , Adulto Joven , Baltimore , Factores de Edad , Tolerancia al Ejercicio , Prueba de EsfuerzoRESUMEN
To delineate the mechanisms by which the ERK1 and ERK2 mitogen-activated protein kinases support mutant KRAS-driven cancer growth, we determined the ERK-dependent phosphoproteome in KRAS-mutant pancreatic cancer. We determined that ERK1 and ERK2 share near-identical signaling and transforming outputs and that the KRAS-regulated phosphoproteome is driven nearly completely by ERK. We identified 4666 ERK-dependent phosphosites on 2123 proteins, of which 79 and 66%, respectively, were not previously associated with ERK, substantially expanding the depth and breadth of ERK-dependent phosphorylation events and revealing a considerably more complex function for ERK in cancer. We established that ERK controls a highly dynamic and complex phosphoproteome that converges on cyclin-dependent kinase regulation and RAS homolog guanosine triphosphatase function (RHO GTPase). Our findings establish the most comprehensive molecular portrait and mechanisms by which ERK drives KRAS-dependent pancreatic cancer growth.
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Proteína Quinasa 1 Activada por Mitógenos , Proteína Quinasa 3 Activada por Mitógenos , Neoplasias Pancreáticas , Fosfoproteínas , Proteoma , Proteínas Proto-Oncogénicas p21(ras) , Animales , Humanos , Ratones , Línea Celular Tumoral , Quinasas Ciclina-Dependientes/metabolismo , Quinasas Ciclina-Dependientes/genética , Sistema de Señalización de MAP Quinasas , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Proteína Quinasa 3 Activada por Mitógenos/metabolismo , Mutación , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Fosfoproteínas/metabolismo , Fosfoproteínas/genética , Fosforilación , Proteínas Proto-Oncogénicas p21(ras)/genética , Proteínas Proto-Oncogénicas p21(ras)/metabolismo , Células HEK293RESUMEN
T cell activation is a complex biological process of naive cells maturing into effector cells. Proteomic and phospho-proteomic approaches have provided critical insights into this process, yet it is not always clear how changes in individual proteins or phosphorylation sites have functional significance. Here, we developed the Phosphorylation Integrated Thermal Shift Assay (PITSA) that combines the measurement of protein or phosphorylation site abundance and thermal stability into a single tandem mass tags experiment and apply this method to study T cell activation. We quantified the abundance and thermal stability of over 7500 proteins and 5000 phosphorylation sites and identified significant differences in chromatin-related, TCR signaling, DNA repair, and proliferative phosphoproteins. PITSA may be applied to a wide range of biological contexts to generate hypotheses as to which proteins or phosphorylation sites are functionally regulated in a given system as well as the mechanisms by which this regulation may occur.
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Activación de Linfocitos , Proteómica , Linfocitos T , Fosforilación , Linfocitos T/metabolismo , Proteómica/métodos , Fosfoproteínas/metabolismo , Animales , Humanos , Estabilidad Proteica , Transducción de Señal , Espectrometría de Masas en Tándem , RatonesRESUMEN
While ultraviolet (UV) radiation damages DNA, eliciting the DNA damage response (DDR), it also damages RNA, triggering transcriptome-wide ribosomal collisions and eliciting a ribotoxic stress response (RSR). However, the relative contributions, timing, and regulation of these pathways in determining cell fate is unclear. Here we use time-resolved phosphoproteomic, chemical-genetic, single-cell imaging, and biochemical approaches to create a chronological atlas of signaling events activated in cells responding to UV damage. We discover that UV-induced apoptosis is mediated by the RSR kinase ZAK and not through the DDR. We identify two negative-feedback modules that regulate ZAK-mediated apoptosis: (1) GCN2 activation limits ribosomal collisions and attenuates ZAK-mediated RSR and (2) ZAK activity leads to phosphodegron autophosphorylation and its subsequent degradation. These events tune ZAK's activity to collision levels to establish regimes of homeostasis, tolerance, and death, revealing its key role as the cellular sentinel for nucleic acid damage.
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Apoptosis , Daño del ADN , Rayos Ultravioleta , Rayos Ultravioleta/efectos adversos , Apoptosis/efectos de la radiación , Fosforilación/efectos de la radiación , Humanos , Transducción de Señal/efectos de la radiación , Proteínas Serina-Treonina Quinasas/metabolismo , Estrés Fisiológico/efectos de la radiación , Ribosomas/metabolismo , Muerte Celular/efectos de la radiaciónRESUMEN
Optical communications (OC) through water bodies is an attractive technology for a variety of applications. Thanks to current single-photon detection capabilities, OC receiver systems can reliably decode very weak transmitted signals. This is the regime where pulse position modulation is an ideal scheme. However, there has to be at least one photon that goes through the pupil of the fore optics and lands in the assigned time bin. We estimate the detectable photon budget as a function of range for propagation through ocean water, both open and coastal. We make realistic assumptions about the water's inherent optical properties, specifically, absorption and scattering coefficients, as well as the strong directionality of the scattering phase function for typical hydrosol populations. We adopt an analytical (hence very fast) path-integral small-angle solution of the radiative transfer equation for multiple forward-peaked scattering across intermediate to large optical distances. Integrals are performed both along the directly transmitted beam (whether or not it is still populated) and radially away from it. We use this modeling framework to estimate transmission of a 1 J pulse of 532 nm light through open ocean and coastal waters. Thresholds for single-photon detection per time bin are a few km and a few 100 m. These are indicative estimates that will be reduced in practice due to sensor noise, background light, turbulence, bubbles, and so on, to be included in future work.
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Malic Enzyme 1 (ME1) plays an integral role in fatty acid synthesis and cellular energetics through its production of NADPH and pyruvate. As such, it has been identified as a gene of interest in obesity, type 2 diabetes, and an array of epithelial cancers, with most work being performed in vitro. The current standard model for ME1 loss in vivo is the spontaneous Mod-1 null allele, which produces a canonically inactive form of ME1. Herein, we describe two new genetically engineered mouse models exhibiting ME1 loss at dynamic timepoints. Using murine embryonic stem cells and Flp/FRT and Cre/loxP class switch recombination, we established a germline Me1 knockout model (Me1 KO) and an inducible conditional knockout model (Me1 cKO), activated upon tamoxifen treatment in adulthood. Collectively, neither the Me1 KO nor Me1 cKO models exhibited deleterious phenotype under standard laboratory conditions. Knockout of ME1 was validated by immunohistochemistry and genotype confirmed by PCR. Transmission patterns favor Me1 loss in Me1 KO mice when maternally transmitted to male progeny. Hematological examination of these models through complete blood count and serum chemistry panels revealed no discrepancy with their wild-type counterparts. Orthotopic pancreatic tumors in Me1 cKO mice grow similarly to Me1 expressing mice. Similarly, no behavioral phenotype was observed in Me1 cKO mice when aged for 52 weeks. Histological analysis of several tissues revealed no pathological phenotype. These models provide a more modern approach to ME1 knockout in vivo while opening the door for further study into the role of ME1 loss under more biologically relevant, stressful conditions.
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Malato Deshidrogenasa , Ratones Noqueados , Fenotipo , Animales , Malato Deshidrogenasa/metabolismo , Malato Deshidrogenasa/genética , Masculino , Ratones , Femenino , Células Germinativas/metabolismo , Ratones Endogámicos C57BLRESUMEN
The tumor suppressor LKB1 is a serine/threonine protein kinase that is frequently mutated in human lung adenocarcinoma (LUAD). LKB1 regulates a complex signaling network that is known to control cell polarity and metabolism; however, the pathways that mediate the tumor-suppressive activity of LKB1 are incompletely defined. To identify mechanisms of LKB1-mediated growth suppression, we developed a spheroid-based cell culture assay to study LKB1-dependent growth. We then performed genome-wide CRISPR screens in spheroidal culture and found that LKB1 suppresses growth, in part, by activating the PIKFYVE lipid kinase. Finally, we used chemical inhibitors and a pH-sensitive reporter to determine that LKB1 impairs growth by promoting the internalization of wild-type EGFR in a PIKFYVE-dependent manner.
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Quinasas de la Proteína-Quinasa Activada por el AMP , Fosfatidilinositol 3-Quinasas , Proteínas Serina-Treonina Quinasas , Esferoides Celulares , Humanos , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Serina-Treonina Quinasas/genética , Quinasas de la Proteína-Quinasa Activada por el AMP/metabolismo , Quinasas de la Proteína-Quinasa Activada por el AMP/genética , Esferoides Celulares/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Fosfatidilinositol 3-Quinasas/genética , Proliferación Celular , Línea Celular Tumoral , Sistemas CRISPR-Cas , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/metabolismo , Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas/genéticaRESUMEN
Genome-wide association studies (GWAS) have become well-powered to detect loci associated with telomere length. However, no prior work has validated genes nominated by GWAS to examine their role in telomere length regulation. We conducted a multi-ancestry meta-analysis of 211,369 individuals and identified five novel association signals. Enrichment analyses of chromatin state and cell-type heritability suggested that blood/immune cells are the most relevant cell type to examine telomere length association signals. We validated specific GWAS associations by overexpressing KBTBD6 or POP5 and demonstrated that both lengthened telomeres. CRISPR/Cas9 deletion of the predicted causal regions in K562 blood cells reduced expression of these genes, demonstrating that these loci are related to transcriptional regulation of KBTBD6 and POP5. Our results demonstrate the utility of telomere length GWAS in the identification of telomere length regulation mechanisms and validate KBTBD6 and POP5 as genes affecting telomere length regulation.
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Estudio de Asociación del Genoma Completo , Homeostasis del Telómero , Telómero , Humanos , Telómero/genética , Telómero/metabolismo , Células K562 , Homeostasis del Telómero/genética , Polimorfismo de Nucleótido Simple , Regulación de la Expresión Génica , Sistemas CRISPR-CasRESUMEN
Phosphorylation of proteins on tyrosine (Tyr) residues evolved in metazoan organisms as a mechanism of coordinating tissue growth1. Multicellular eukaryotes typically have more than 50 distinct protein Tyr kinases that catalyse the phosphorylation of thousands of Tyr residues throughout the proteome1-3. How a given Tyr kinase can phosphorylate a specific subset of proteins at unique Tyr sites is only partially understood4-7. Here we used combinatorial peptide arrays to profile the substrate sequence specificity of all human Tyr kinases. Globally, the Tyr kinases demonstrate considerable diversity in optimal patterns of residues surrounding the site of phosphorylation, revealing the functional organization of the human Tyr kinome by substrate motif preference. Using this information, Tyr kinases that are most compatible with phosphorylating any Tyr site can be identified. Analysis of mass spectrometry phosphoproteomic datasets using this compendium of kinase specificities accurately identifies specific Tyr kinases that are dysregulated in cells after stimulation with growth factors, treatment with anti-cancer drugs or expression of oncogenic variants. Furthermore, the topology of known Tyr signalling networks naturally emerged from a comparison of the sequence specificities of the Tyr kinases and the SH2 phosphotyrosine (pTyr)-binding domains. Finally we show that the intrinsic substrate specificity of Tyr kinases has remained fundamentally unchanged from worms to humans, suggesting that the fidelity between Tyr kinases and their protein substrate sequences has been maintained across hundreds of millions of years of evolution.
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Fosfotirosina , Proteínas Tirosina Quinasas , Especificidad por Sustrato , Tirosina , Animales , Humanos , Secuencias de Aminoácidos , Evolución Molecular , Espectrometría de Masas , Fosfoproteínas/química , Fosfoproteínas/metabolismo , Fosforilación , Fosfotirosina/metabolismo , Proteínas Tirosina Quinasas/efectos de los fármacos , Proteínas Tirosina Quinasas/metabolismo , Proteoma/química , Proteoma/metabolismo , Proteómica , Transducción de Señal , Dominios Homologos src , Tirosina/metabolismo , Tirosina/químicaRESUMEN
CK1 kinases participate in many signaling pathways, and their regulation is of meaningful biological consequence. CK1s autophosphorylate their C-terminal noncatalytic tails, and eliminating these tails increases substrate phosphorylation in vitro, suggesting that the autophosphorylated C-termini act as inhibitory pseudosubstrates. To test this prediction, we comprehensively identified the autophosphorylation sites on Schizosaccharomyces pombe Hhp1 and human CK1ε. Phosphoablating mutations increased Hhp1 and CK1ε activity toward substrates. Peptides corresponding to the C-termini interacted with the kinase domains only when phosphorylated, and substrates competitively inhibited binding of the autophosphorylated tails to the substrate binding grooves. Tail autophosphorylation influenced the catalytic efficiency with which CK1s targeted different substrates, and truncating the tail of CK1δ broadened its linear peptide substrate motif, indicating that tails contribute to substrate specificity as well. Considering autophosphorylation of both T220 in the catalytic domain and C-terminal sites, we propose a displacement specificity model to describe how autophosphorylation modulates substrate specificity for the CK1 family.
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Proteínas de Schizosaccharomyces pombe , Humanos , Secuencia de Aminoácidos , Caseína Cinasa 1 épsilon/metabolismo , Caseína Cinasa 1 épsilon/genética , Dominio Catalítico , Mutación , Péptidos/metabolismo , Péptidos/química , Fosforilación , Unión Proteica , Schizosaccharomyces/metabolismo , Schizosaccharomyces/genética , Proteínas de Schizosaccharomyces pombe/metabolismo , Proteínas de Schizosaccharomyces pombe/química , Proteínas de Schizosaccharomyces pombe/genética , Especificidad por SustratoRESUMEN
Mosaic loss of Y (mLOY) is the most common somatic chromosomal alteration detected in human blood. The presence of mLOY is associated with altered blood cell counts and increased risk of Alzheimer's disease, solid tumors, and other age-related diseases. We sought to gain a better understanding of genetic drivers and associated phenotypes of mLOY through analyses of whole genome sequencing of a large set of genetically diverse males from the Trans-Omics for Precision Medicine (TOPMed) program. This approach enabled us to identify differences in mLOY frequencies across populations defined by genetic similarity, revealing a higher frequency of mLOY in the European American (EA) ancestry group compared to those of Hispanic American (HA), African American (AA), and East Asian (EAS) ancestry. Further, we identified two genes ( CFHR1 and LRP6 ) that harbor multiple rare, putatively deleterious variants associated with mLOY susceptibility, show that subsets of human hematopoietic stem cells are enriched for activity of mLOY susceptibility variants, and that certain alleles on chromosome Y are more likely to be lost than others.
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Mass spectrometry-based phosphoproteomics offers a comprehensive view of protein phosphorylation, but limited knowledge about the regulation and function of most phosphosites restricts our ability to extract meaningful biological insights from phosphoproteomics data. To address this, we combine machine learning and phosphoproteomic data from 1,195 tumor specimens spanning 11 cancer types to construct CoPheeMap, a network mapping the co-regulation of 26,280 phosphosites. Integrating network features from CoPheeMap into a machine learning model, CoPheeKSA, we achieve superior performance in predicting kinase-substrate associations. CoPheeKSA reveals 24,015 associations between 9,399 phosphosites and 104 serine/threonine kinases, including many unannotated phosphosites and under-studied kinases. We validate the accuracy of these predictions using experimentally determined kinase-substrate specificities. By applying CoPheeMap and CoPheeKSA to phosphosites with high computationally predicted functional significance and cancer-associated phosphosites, we demonstrate the effectiveness of these tools in systematically illuminating phosphosites of interest, revealing dysregulated signaling processes in human cancer, and identifying under-studied kinases as putative therapeutic targets.
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Typified by LiTMP and TMPMgCl.LiCl, (TMP=2,2,6,6-tetramethylpiperidide), s-block metal amides have found widespread applications in arene deprotonative metalation. On the contrary, transition metal amides lack sufficient basicity to activate these substrates. Breaking new ground in this field, here we present the synthesis and full characterisation of earth-abundant transition metals M(TMP)2 (M=Fe, Co). Uncovering a new reactivity profile towards fluoroarenes, these amide complexes can promote direct M-H exchange processes regioselectively using one or two of their basic amide arms. Remarkably, even when using a perfluorinated substrate, selective C-H metalation occurs leaving C-F bonds intact. Their kinetic basicity can be boosted by LiCl or NBu4Cl additives which enables formation of kinetically activated ate species. Combining spectroscopic and structural studies with DFT calculations, mechanistic insights have been gained on how these low polarity metalation processes take place. M(TMP)2 can also be used to access ferrocene and cobaltocene by direct deprotonation of cyclopentadiene and undergo efficient CO2 insertion of both amide groups under mild reaction conditions.