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Initiation of cyst formation in autosomal dominant polycystic kidney disease (ADPKD) occurs when kidney tubule cells are rendered null for either PKD1 or PKD2 by somatic 'second hit' mutations. Subsequent cyst progression remodels the organ through changes in tubule cell shape, proliferation and secretion. The kidney develops inflammation and fibrosis. We constructed a mouse model in which adult inactivation of either Pkd gene can be followed by reactivation of the gene at a later time. Using this model, we show that re-expression of Pkd genes in cystic kidneys results in rapid reversal of ADPKD. Cyst cell proliferation is reduced, autophagy is activated and cystic tubules with expanded lumina lined by squamoid cells revert to normal lumina lined by cuboidal cells. see more Increases in inflammation, extracellular matrix deposition and myofibroblast activation are reversed, and the kidneys become smaller. We conclude that phenotypic features of ADPKD are reversible and that the kidney has an unexpected capacity for plasticity controlled at least in part by ADPKD gene function.Directed evolution can generate proteins with tailor-made activities. However, full-length genotypes, their frequencies and fitnesses are difficult to measure for evolving gene-length biomolecules using most high-throughput DNA sequencing methods, as short read lengths can lose mutation linkages in haplotypes. Here we present Evoracle, a machine learning method that accurately reconstructs full-length genotypes (R2 = 0.94) and fitness using short-read data from directed evolution experiments, with substantial improvements over related methods. We validate Evoracle on phage-assisted continuous evolution (PACE) and phage-assisted non-continuous evolution (PANCE) of adenine base editors and OrthoRep evolution of drug-resistant enzymes. Evoracle retains strong performance (R2 = 0.86) on data with complete linkage loss between neighboring nucleotides and large measurement noise, such as pooled Sanger sequencing data (~US$10 per timepoint), and broadens the accessibility of training machine learning models on gene variant fitnesses. Evoracle can also identify high-fitness variants, including low-frequency 'rising stars', well before they are identifiable from consensus mutations.Single-cell Hi-C (scHi-C) can identify cell-to-cell variability of three-dimensional (3D) chromatin organization, but the sparseness of measured interactions poses an analysis challenge. Here we report Higashi, an algorithm based on hypergraph representation learning that can incorporate the latent correlations among single cells to enhance overall imputation of contact maps. Higashi outperforms existing methods for embedding and imputation of scHi-C data and is able to identify multiscale 3D genome features in single cells, such as compartmentalization and TAD-like domain boundaries, allowing refined delineation of their cell-to-cell variability. Moreover, Higashi can incorporate epigenomic signals jointly profiled in the same cell into the hypergraph representation learning framework, as compared to separate analysis of two modalities, leading to improved embeddings for single-nucleus methyl-3C data. In an scHi-C dataset from human prefrontal cortex, Higashi identifies connections between 3D genome features and cell-type-specific gene regulation. Higashi can also potentially be extended to analyze single-cell multiway chromatin interactions and other multimodal single-cell omics data.The identification of actionable tumor antigens is indispensable for the development of several cancer immunotherapies, including T cell receptor-transduced T cells and patient-specific mRNA or peptide vaccines. Most known tumor antigens have been identified through extensive molecular characterization and are considered canonical if they derive from protein-coding regions of the genome. By eluting human leukocyte antigen-bound peptides from tumors and subjecting these to mass spectrometry analysis, the peptides can be identified by matching the resulting spectra against reference databases. Recently, mass-spectrometry-based immunopeptidomics has enabled the discovery of noncanonical antigens-antigens derived from sequences outside protein-coding regions or generated by noncanonical antigen-processing mechanisms. Coupled with transcriptomics and ribosome profiling, this method enables the identification of thousands of noncanonical peptides, of which a substantial fraction may be detected exclusively in tumors. Spectral matching against the immense noncanonical reference may generate false positives. However, sensitive mass spectrometry, analytical validation and advanced bioinformatics solutions are expected to uncover the full landscape of presented antigens and clinically relevant targets.Recent efforts have succeeded in surveying open chromatin at the single-cell level, but high-throughput, single-cell assessment of heterochromatin and its underlying genomic determinants remains challenging. We engineered a hybrid transposase including the chromodomain (CD) of the heterochromatin protein-1α (HP-1α), which is involved in heterochromatin assembly and maintenance through its binding to trimethylation of the lysine 9 on histone 3 (H3K9me3), and developed a single-cell method, single-cell genome and epigenome by transposases sequencing (scGET-seq), that, unlike single-cell assay for transposase-accessible chromatin with sequencing (scATAC-seq), comprehensively probes both open and closed chromatin and concomitantly records the underlying genomic sequences. We tested scGET-seq in cancer-derived organoids and human-derived xenograft (PDX) models and identified genetic events and plasticity-driven mechanisms contributing to cancer drug resistance. Next, building upon the differential enrichment of closed and open chromatin, we devised a method, Chromatin Velocity, that identifies the trajectories of epigenetic modifications at the single-cell level. Chromatin Velocity uncovered paths of epigenetic reorganization during stem cell reprogramming and identified key transcription factors driving these developmental processes. scGET-seq reveals the dynamics of genomic and epigenetic landscapes underlying any cellular processes.Live cell imaging with high spatiotemporal resolution and high detection sensitivity facilitates the study of the dynamics of cellular structure and function. However, extracting high-resolution 4D (3D space plus time) information from live cells remains challenging, because current methods are slow, require high peak excitation intensities or suffer from high out-of-focus background. Here we present 3D interferometric lattice light-sheet (3D-iLLS) imaging, a technique that requires low excitation light levels and provides high background suppression and substantially improved volumetric resolution by combining 4Pi interferometry with selective plane illumination. We demonstrate that 3D-iLLS has an axial resolution and single-particle localization precision of 100 nm (FWHM) and less then 10 nm (1σ), respectively. We illustrate the performance of 3D-iLLS in a range of systems single messenger RNA molecules, nanoscale assemblies of transcription regulators in the nucleus, the microtubule cytoskeleton and mitochondria organelles. The enhanced 4D resolution and increased signal-to-noise ratio of 3D-iLLS will facilitate the analysis of biological processes at the sub-cellular level.Current archaeological research on cultigens emphasizes the protracted and intimate human interactions with wild species that defined paths to domestication and, with certain plants, profoundly impacted humanity. Tobacco arguably has had more impact on global patterns in history than any other psychoactive substance, but how deep its cultural ties extend has been widely debated. Excavations at the Wishbone site, directed at the hearth-side activities of the early inhabitants of North America's desert west, have uncovered evidence for human tobacco use approximately 12,300 years ago, 9,000 years earlier than previously documented. Here we detail the preservation context of the site, discuss its cultural affiliation and suggest ways that the tobacco may have been used. The find has implications for our understanding of deep-time human use of intoxicants and its sociocultural intersection with food crop domestication.

The CpG island methylator phenotype of neuroblastoma (NBL) is strongly associated with poor prognosis and can be targeted by 5-aza-2'-deoxycytidine (5-aza-dC). Differentiation therapy is a standard maintenance therapy for high-risk NBLs. However, the in vivo effect of tamibarotene, a synthetic retinoic acid, and the efficacy of its combination with 5-aza-dC have not been studied. Here, we conducted a preclinical study to assess the in vivo tamibarotene effect and the combination.

Treatment effects were analysed by in vitro cell growth and differentiation state and by in vivo xenograft suppression. Demethylated genes were analysed by DNA methylation microarrays and geneset enrichment.

Tamibarotene monotherapy induced neural extension and upregulation of differentiation markers of NBL cells in vitro, and tumour regression without severe side effects in vivo. 5-Aza-dC monotherapy suppressed tumour growth both in vitro and in vivo, and induced demethylation of genes related to nervous system development and function. Pre-treatment with 5-aza-dC in vitro enhanced upregulation of differentiation markers and genes involved in retinoic acid signaling. Pre-treatment with 5-aza-dC in vivo significantly suppressed tumour growth and reduced the variation in tumour sizes.

Epigenetic drug-based differentiation therapy using 5-aza-dC and TBT is a promising strategy for refractory NBLs.

Epigenetic drug-based differentiation therapy using 5-aza-dC and TBT is a promising strategy for refractory NBLs.Because of the blood-tumour barrier and cross-reactivity with healthy tissues, immune checkpoint blockade therapy against glioblastoma has inadequate efficacy and is associated with a high risk of immune-related adverse events. Here we show that anti-programmed death-ligand 1 antibodies conjugated with multiple poly(ethylene glycol) (PEG) chains functionalized to target glucose transporter 1 (which is overexpressed in brain capillaries) and detaching in the reductive tumour microenvironment augment the potency and safety of checkpoint blockade therapy against glioblastoma. In mice bearing orthotopic glioblastoma tumours, a single dose of glucosylated and multi-PEGylated antibodies reinvigorated antitumour immune responses, induced immunological memory that protected the animals against rechallenge with tumour cells, and suppressed autoimmune responses in the animals' healthy tissues. Drug-delivery formulations leveraging multivalent ligand interactions and the properties of the tumour microenvironment to facilitate the crossing of blood-tumour barriers and increase drug specificity may enhance the efficacy and safety of other antibody-based therapies.The term scrotoplasty embraces several techniques which aim to restore a normal scrotal appearance and function. We provide here a quick reference tool to allow the urologist to select the appropriate surgical strategy among the several available options. A comprehensive research was carried out on MEDLINE/PubMed to identify relevant studies concerning this topic, including a range of key words, e.g., scrotoplasty, ventral phalloplasty, scrotal reconstruction, scrotomegaly, penoscrotal web, scrotal lifting, scrotal reduction, scrotectomy, scrotal lymphoedema. Scrotal skin defects may be related with Fournier's gangrene, traumatic events, and surgery for genital cancers or peno-scrotal lymphoedema. The reconstructive management of these conditions is relatively reproducible in the hands of experienced urologists, if aware of the basics of scrotal surgery. Primary tension-free wound closure and local pedicled flaps typically allow optimal surgical outcomes for repairing most of these scrotal defects, with split-thickness skin grafts (STSGs) and/or distant flaps being required only when dealing with extensive skin losses.

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