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Altres ajuts: Acknowledgements TAM, LG, NTC, I-JL, RT, JRH, and SR were funded by Medical Research Council (MRC, UK) Molecular Haematology Unit grant MC_UU_12009/6, MC_UU_00016/6, and MR/ M003221/1. AR was supported by a Bloodwise Clinician Scientist Fellowship (grants: 14041 and 17001), Wellcome Trust Clinical Research Career Development Fellowship (216632/Z/19/Z), Lady Tata Memorial International Fellowship, and EHA-ASH Translational Research Training in Hematology Fellowship. SOB was funded by the Department of Paediatrics and Alexander Thatte Fund, University of Oxford. DJHFK is funded by a CIHR Postdoctoral Fellowship. IR is supported by the NIHR Oxford BRC, by a Bloodwise Program Grant (13001) and by the MRC Molecular Haematology Unit (MC_UU_12009/14). PV via the Molecular Haematology Unit (MC_UU_12009) and the National Institute for Health Research (NIHR) Oxford Biomedical Research Centre (BRC) Programme. We would like to acknowledge the WIMM Flow Cytometry Facility which is supported by the MRC HIU, MRC MHU (MC_UU_12009), NIHR Oxford BRC, Kay Kendall Leukemia Fund (KKL1057), John Fell Fund (131/030 and 101/517), the EPA fund (CF182 and CF170), and by the WIMM Strategic Alliance awards G0902418 and MC_UU_12025. We thank the High-Throughput Genomics Group at the Wellcome Trust Centre for Human Genetics (funded by Wellcome Trust Grant Reference 090532/Z/09/Z); the MRC WIMM Centre for Computational Biology (CCB), Radcliffe Department of Medicine, University of Oxford; and Jelena Telenius for the use of her pipelines. B-ALL work in PM's lab is financially supported by [...], the Fundación Uno entre Cienmil, the Fundación Leo Messi. PM also acknowledges structural support from the Obra Social La Caixa-Fundaciò Josep Carreras. The human fetal material was provided by the Joint MRC/ Wellcome Trust Grant 099175/Z/ 12/Z Human Developmental Biology Resource (http://hdbr.org). We gratefully acknowledge the kind generosity of patients, their parents, and staff at Great Ormond Street Hospital, London. MLL gene rearrangements (MLLr) are a common cause of aggressive, incurable acute lymphoblastic leukemias (ALL) in infants and children, most of which originate in utero. The most common MLLr produces an MLL-AF4 fusion protein. MLL-AF4 promotes leukemogenesis by activating key target genes, mainly through recruitment of DOT1L and increased histone H3 lysine-79 methylation (H3K79me2/3). One key MLL-AF4 target gene is PROM1, which encodes CD133 (Prominin-1). CD133 is a pentaspan transmembrane glycoprotein that represents a potential pan-cancer target as it is found on multiple cancer stem cells. Here we demonstrate that aberrant PROM1/CD133 expression is essential for leukemic cell growth, mediated by direct binding of MLL-AF4. Activation is controlled by an intragenic H3K79me2/3 enhancer element (KEE) leading to increased enhancer-promoter interactions between PROM1 and the nearby gene TAPT1. This dual locus regulation is reflected in a strong correlation of expression in leukemia. We find that in PROM1/CD133 non-expressing cells, the PROM1 locus is repressed by polycomb repressive complex 2 (PRC2) binding, associated with reduced expression of TAPT1, partially due to loss of interactions with the PROM1 locus. Together, these results provide the first detailed analysis of PROM1/CD133 regulation that explains CD133 expression in MLLr ALL.

Precise, analogue regulation of gene expression is critical for cellular function in mammals. In contrast, widely employed experimental and therapeutic approaches such as knock-in/out strategies are more suitable for binary control of gene activity. Here we report on a method for precise control of gene expression levels in mammalian cells using engineered microRNA response elements (MREs). First, we measure the efficacy of thousands of synthetic MRE variants under the control of an endogenous microRNA by high-throughput sequencing. Guided by this data, we establish a library of microRNA silencing-mediated fine-tuners (miSFITs) of varying strength that can be employed to precisely control the expression of user-specified genes. We apply this technology to tune the T-cell co-inhibitory receptor PD-1 and to explore how antigen expression influences T-cell activation and tumour growth. Finally, we employ CRISPR/Cas9 mediated homology directed repair to introduce miSFITs into the BRCA1 3′UTR, demonstrating that this versatile tool can be used to tune endogenous genes., Analogue regulation of gene expression is important for normal function in mammals but existing genetic technologies are designed to achieve ON/OFF control. Here the authors develop synthetic microRNA silencing-mediated fine-tuners (miSFITs) to precisely control target gene expression levels.

Hepcidin regulates systemic iron homeostasis. Suppression of hepcidin expression occurs physiologically in iron deficiency and increased erythropoiesis but is pathologic in thalassemia and hemochromatosis. Here we show that epigenetic events govern hepcidin expression. Erythropoiesis and iron deficiency suppress hepcidin via erythroferrone-dependent and -independent mechanisms, respectively, in vivo, but both involve reversible loss of H3K9ac and H3K4me3 at the hepcidin locus. In vitro, pan-histone deacetylase inhibition elevates hepcidin expression, and in vivo maintains H3K9ac at hepcidin-associated chromatin and abrogates hepcidin suppression by erythropoietin, iron deficiency, thalassemia, and hemochromatosis. Histone deacetylase 3 and its cofactor NCOR1 regulate hepcidin; histone deacetylase 3 binds chromatin at the hepcidin locus, and histone deacetylase 3 knockdown counteracts hepcidin suppression induced either by erythroferrone or by inhibiting bone morphogenetic protein signaling. In iron deficient mice, the histone deacetylase 3 inhibitor RGFP966 increases hepcidin, and RNA sequencing confirms hepcidin is one of the genes most differentially regulated by this drug in vivo. We conclude that suppression of hepcidin expression involves epigenetic regulation by histone deacetylase 3., Hepcidin controls systemic iron levels by inhibiting intestinal iron absorption and iron recycling. Here, Pasricha et al. demonstrate that the hepcidin-chromatin locus displays HDAC3-mediated reversible epigenetic modifications during both erythropoiesis and iron deficiency.

Survival rates for children and adults carrying mutations in the Mixed Lineage Leukemia (MLL) gene continue to have a very poor prognosis. The most common MLL mutation in ALL is the t(4;11)(q21;q23) chromosome translocation that fuses MLL in frame with the AF4 gene producing MLL-AF4 and AF4-MLL fusion proteins. Previously, we demonstrated that MLL-AF4 binds to the BCL-2 gene and directly activates it through DOT1L recruitment and increased H3K79me2/3 levels. Here, we perform a detailed analysis of MLL-AF4 regulation of the entire BCL-2 family. By measuring nascent RNA production in MLL-AF4 knockdowns, we find that of all the BCL-2 family genes, MLL-AF4 directly controls the active transcription of both BCL-2 and MCL-1, and also represses BIM via binding of the polycomb group repressor 1 (PRC1) complex component CBX8. We further analyze MLL-AF4 activation of the BCL-2 gene using Capture C and identify a BCL-2 specific enhancer, consisting of two clusters of H3K27Ac at the 3’end of the gene. Loss of MLL-AF4 activity results in a reduction of H3K79me3 levels in the gene body and H3K27Ac levels at the 3’ BCL-2 enhancer, revealing a novel regulatory link between these two histone marks and MLL-AF4 mediated activation of BCL-2.

This techno-economic project will provide a greater understanding of the options available to modify or improve the physical and chemical characteristics of different types of UK-derived 2nd generation energy biomass feedstocks, that may otherwise reduce the cost-effective performance of conversion technologies.This report assesses the current techno-economic status of biomass pre-processing, combustion and gasification technologies used to transform forestry and perennial energy crop feedstocks into heat, power and syngas.The report uses a common review framework to assess all technologies, including technology descriptions, status, impacts of feedstock choice and options for improvement.Conversion technologiescombustionunderfed StokerMoving BedBubbling Fluidised BedCirculating Fluidised BedDust SuspensionGasificationUpdraft GasifiersDowndraft GasifiersBubbling Fluidised Bed GasifiersCirculating Fluidised Bed GasifiersDual Fluidised Bed GasifiersEntrained Flow GasificationSyngas BoilerSyngas engine/CHPSyngas CCGTPre-processing TechnologiesWater washing & Chemical washingForced DryingBriquettingScreeningChippingPelletingPyrolysisTorrefactionSteam ExplosionAmmonia Fibre ExpansionShorter descriptions are also provided for a further set of typically less mature conversion and pre-processing technology options, as part of a horizon scanning exercise.Technologies with lower Technology Readiness LevelsTechnologies with higher Technology Readiness LevelsSummary of TRLsThis report enables the reader to understand which technologies are nearest to/furthest from being commercialised, which are cheapest on a stand-alone basis, and the impact that different feedstock characteristics have on the operation and costs of the technologies.The report presents the techno-economic data gathered on these technologies for use in the modelling of different bioenergy supply chains later in the TEAB project, highlighting any data gaps and where uncertainty ranges are highest

e techno-economic project will provide a greater understanding of the options available to modify or improve the physical and chemical characteristics of different types of UK-derived 2nd generation energy biomass feedstocks, that may otherwise reduce the cost-effective performance of conversion technologiesThis Deliverable 1a report exists as a standalone document, which can be read alongside the “Deliverable 1 - Review and benchmarking report” within the ETI’s Techno-Economic Assessment of Biomass Pre-Processing (TEABPP) study.The original report ‘D1’ excluded technologies below 200kWth input; hence this report ‘D1a’ is focused on the state-of-the-art, techno-economics and real-world issues faced by these small-scale combustion technologies. In this report, the technologies typically used for combustion of biomass have been separated into three types (although some plant designs exist that incorporate multiple technologies). Based on the fuel feeding methods and the operation of the fuel bed, the main technologies are as follows:a manually-fed boiler,an automatically-fed boiler with a fixed combustion bed, andan automatically-fed boiler with a moving combustion bed.The report also covers Organic Rankine Cycle technologies (as a Stirling engines are covered in Section 6.3.4.1 of D1 Report), detailing their development status, integration with biomass-fired systems, their strengths, weaknesses and main suppliers.Details of the European biomass fuel standards that have been developed are also covered within the report, together with fuel quality assurance schemes that enable biomass feedstocks to meet boiler specifications and avoid issues when burnt in biomass boilers