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Background: Stroke patients often present circadian disruption due to multiple causes e.g., primary disease, comorbidities, medication, immobilization, reduced daylight entrainment and sleep disturbances. Objective: To investigate the circadian rhythm of temperature in forehead skin in patients with moderate to severe stroke admitted for rehabilitation. Methods: A physiologic study in form of a secondary analysis of a former randomized study. In total 27 patients with moderate to severe stroke were included between May 1st 2014, and June 1st 2015. Circadian temperature was collected approx. seven days after admission at the acute stroke unit by a skin surface temperature probe as part of a Polysomnography (PSG) measurement. Results: Temperature variations show no circadian rhythm (Type 3 tests of fixed effects by SAS, p = 0.1610). The median temperature variance did fluctuate, but not significantly, and the small changes in circadian temperature variance did not follow the normal temperature variance. Conclusion: Patients with moderate to severe stroke show an abrogated circadian rhythm of temperature. There is an unmet need to understand the mechanisms for this, significance for stroke outcome and treatment.
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Background and purpose: Biomarkers for prediction of outcome in patients with pancreatic cancer are wanted in order to personalize the treatment. This study investigated the value of longitudinal diffusion-weighted magnetic resonance imaging (DWI) for prediction of overall survival (OS) in patients with locally advanced pancreatic cancer (LAPC) treated with stereotactic body radiotherapy (SBRT). Materials and methods: The study included 45 patients with LAPC who received 5 fractions of 10 Gy on a 1.5T MRI-Linac. DWI was acquired prior to irradiation at each fraction. The analysis included baseline values and time-trends of the apparent diffusion coefficient (ADC) and DWI parameters obtained using a decomposition method. A multivariable Cox proportional hazards model for OS was made using best-subset selection, using cross-validation based on Bootstrap. Results: The median OS from the first day of SBRT was 15.5 months (95% CI: 13.2-20.6), and the median potential follow-up time was 19.8 months. The best-performing multivariable model for OS included two decomposition-based DWI parameters: one baseline and one time-trend parameter. The C-Harrell index describing the model's discriminating power was 0.754. High baseline ADC values were associated with reduced OS, whereas no association between the ADC time-trend and OS was observed. Conclusion: Decomposition-based DWI parameters indicated value in the prediction of OS in LAPC. A DWI time-trend parameter was included in the best-performing model, indicating a potential benefit of acquiring longitudinal DWI during the SBRT course. These findings support both baseline and longitudinal DWI as candidate prognostic biomarkers, which may become tools for personalization of the treatment of patients with LAPC.
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X-ray crystallography provides a distinctive view on the three-dimensional structure of crystals. To reconstruct the electron density map, the complex structure factors [Formula: see text] of a sufficiently large number of diffracted reflections must be known. In a conventional experiment, only the amplitudes [Formula: see text] are obtained, and the phases Ï are lost. This is the crystallographic phase problem. In this work, we show that a neural network, trained on millions of artificial structure data, can solve the phase problem at a resolution of only 2 angstroms, using only 10 to 20% of the data needed for direct methods. The network works in common space groups and for modest unit-cell dimensions and suggests that neural networks could be used to solve the phase problem in the general case for weakly scattering crystals.
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Kainate receptors play an important role in the central nervous system by mediating postsynaptic excitatory neurotransmission and modulating the release of the inhibitory neurotransmitter GABA through a presynaptic mechanism. To date, only three structures of the ligand-binding domain (LBD) of the kainate receptor subunit GluK1 in complex with positive allosteric modulators have been determined by X-ray crystallography, all belonging to class II modulators. Here, we report a high-resolution structure of GluK1-LBD in complex with kainate and BPAM538, which belongs to the full-spanning class III. One BPAM538 molecule binds at the GluK1 dimer interface, thereby occupying two allosteric binding sites simultaneously. BPAM538 stabilizes the active receptor conformation with only minor conformational changes being introduced to the receptor. Using a calcium-sensitive fluorescence-based assay, a 5-fold potentiation of the kainate response (100 µM) was observed in presence of 100 µM BPAM538 at GluK1(Q)b, whereas no potentiation was observed at GluK2(VCQ)a. Using electrophysiology recordings of outside-out patches excised from HEK293 cells, BPAM538 increased the peak response of GluK1(Q)b co-expressed with NETO2 to rapid application of 10 mM L-glutamate with 130 ± 20 %, and decreased desensitization determined as the steady-state/peak response ratio from 23 ± 2 % to 90 ± 4 %. Based on dose-response relationship experiments on GluK1(Q)b the EC50 of BPAM538 was estimated to be 58 ± 29 µM.
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Although only a fraction of CTCF motifs are bound in any cell type, and approximately half of the occupied sites overlap cohesin, the mechanisms underlying cell-type specific attachment and ability to function as a chromatin organizer remain unknown. To investigate the relationship between CTCF and chromatin we applied a combination of imaging, structural and molecular approaches, using a series of brain and cancer associated CTCF mutations that act as CTCF perturbations. We demonstrate that binding and the functional impact of WT and mutant CTCF depend not only on the unique properties of each protein, but also on the genomic context of bound sites. Our studies also highlight the reciprocal relationship between CTCF and chromatin, demonstrating that the unique binding properties of WT and mutant proteins have a distinct impact on accessibility, TF binding, cohesin overlap, chromatin interactivity and gene expression programs, providing insight into their cancer and brain related effects.
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PURPOSE: Nocturnal urine volume and bladder reservoir function are key pathogenic factors behind monosymptomatic nocturnal enuresis (MNE). We investigated the predictive value of these together with other demographic and clinical variables for response to first-line treatments in children with MNE. MATERIALS AND METHODS: A randomized, controlled, international, multicenter study was conducted in 324 treatment-naïve children (6-14 years old) with primary MNE. The children were randomized to treatment with or without prior consideration of voiding diaries. In the group where treatment choice was based on voiding diaries, children with nocturnal polyuria and normal maximum voided volume (MVV) received desmopressin (dDAVP) treatment, and children with reduced MVV and no nocturnal polyuria received an enuresis alarm. In the other group, treatment with dDAVP or alarm was randomly allocated. RESULTS: A total of 281 children (72% males) were qualified for statistical analysis. The change of responding to treatment was 21% higher in children where treatment was individualized compared to children where treatment was randomly selected (risk ratio = 1.21 [1.02-1.45], P = .032). In children with reduced MVV and no nocturnal polyuria (35% of all children), individualized treatment was associated with a 46% improvement in response compared to random treatment selection (risk ratio = 1.46 [1.14-1.87], P = .003). Furthermore, we developed a clinically relevant prediction model for response to dDAVP treatment (receiver operating characteristic curve 0.85). CONCLUSIONS: The present study demonstrates that treatment selection based on voiding diaries improves response to first-line treatment, particularly in specific subtypes. Information from voiding diaries together with clinical and demographic information provides the basis for predicting response. CLINICAL TRIAL REGISTRATION NO.: NCT03389412.
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Transcriptional coregulators and transcription factors (TFs) contain intrinsically disordered regions (IDRs) that are critical for their association and function in gene regulation. More recently, IDRs have been shown to promote multivalent protein-protein interactions between coregulators and TFs to drive their association into condensates. By contrast, here we demonstrate how the IDR of the corepressor LSD1 excludes TF association, acting as a dynamic conformational switch that tunes repression of active cis-regulatory elements. Hydrogen-deuterium exchange shows that the LSD1 IDR interconverts between transient open and closed conformational states, the latter of which inhibits partitioning of the protein's structured domains with TF condensates. This autoinhibitory switch controls leukemic differentiation by modulating repression of active cis-regulatory elements bound by LSD1 and master hematopoietic TFs. Together, these studies unveil alternative mechanisms by which disordered regions and their dynamic crosstalk with structured regions can shape coregulator-TF interactions to control cis-regulatory landscapes and cell fate.
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Elementos Facilitadores Genéticos , Histona Desmetilases , Histona Desmetilases/metabolismo , Histona Desmetilases/genética , Humanos , Proteínas Intrinsicamente Desordenadas/metabolismo , Proteínas Intrinsicamente Desordenadas/genética , Proteínas Intrinsicamente Desordenadas/química , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Animais , Ligação Proteica , Camundongos , Diferenciação Celular , Inativação GênicaRESUMO
Device-independent quantum key distribution (DIQKD) aims at generating secret keys between distant parties without the parties trusting their devices. We investigate a proposal for performing fully photonic DIQKD, based on single photon sources and heralding measurements at a central station placed between the two parties. We derive conditions to attain non-zero secret-key rates in terms of the photon efficiency, indistinguishability and the second order autocorrelation function of the single-photon sources. Exploiting new results on the security bound of such protocols allows us to reduce the requirements on the physical parameters of the setup. Our analysis shows that in the considered schemes, key rates of several hundreds of secret bits per second are within reach at distances of several tens of kilometers.
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Approximately 11% of human genes are transcribed by a bidirectional promoter (BDP), defined as two genes with <1 kb between their transcription start sites. Despite their evolutionary conservation and enrichment for housekeeping genes and oncogenes, the regulatory role of BDPs remains unclear. BDPs have been suggested to facilitate gene coregulation and/or decrease expression noise. This review discusses these potential regulatory functions through the context of six prospective underlying mechanistic models: a single nucleosome free region, shared transcription factor/regulator binding, cooperative negative supercoiling, bimodal histone marks, joint activation by enhancer(s), and RNA-mediated recruitment of regulators. These molecular mechanisms may act independently and/or cooperatively to facilitate the coregulation and/or decreased expression noise predicted of BDPs.
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Regulação da Expressão Gênica , Regiões Promotoras Genéticas , Humanos , Modelos Moleculares , Animais , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Transcrição GênicaRESUMO
BACKGROUND: Several studies have analyzed the effect of anticoagulants on cancer survival, with varying results. This study aimed to assess the effect of warfarin on survival in patients with colorectal cancer (CRC) in relation to timing of warfarin initiation. METHODS: Data on 10,051 individuals aged ≥45 years in the Västra Götaland Region of Sweden, and diagnosed with CRC between 2000 and 2009, were obtained from the Swedish National Cancer Register. Those who received warfarin treatment (n= 1,216) during the study period were labeled cases and those who did not (n= 8,873) were labeled controls. For statistical analysis, National Cancer Register data were merged with mortality data from the Swedish National Cause of Death register and data from the regional warfarin treatment register. RESULTS: Hazard rates for CRC-specific mortality were lower in cases than in controls. When warfarin was used for any reason at any time, cases had a significantly lower CRC-specific mortality than controls among both women (hazard ratio [HR] 0.71; 95 % confidence interval [CI] 0.59-0.85; p= 0.0002) and men (HR 0.61; 95 % CI 0.52-0.72; p < 0001). Warfarin treatment after CRC diagnosis reduced CRC-specific mortality by 80 %; however, when warfarin was given before or ≥5 years after diagnosis, CRC-specific mortality did not significantly decrease. The number needed to treat to avoid one death was four. CONCLUSION: Use of warfarin early after diagnosis in patients with CRC was associated with improved survival.
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Vortioxetine (VTX) is a recently approved antidepressant that targets a variety of serotonin receptors. Here, we investigate the drug's molecular mechanism of operation at the serotonin 5-HT3 receptor (5-HT3R), which features two properties: VTX acts differently on rodent and human 5-HT3R, and VTX appears to suppress any subsequent response to agonists. Using a combination of cryo-EM, electrophysiology, voltage-clamp fluorometry and molecular dynamics, we show that VTX stabilizes a resting inhibited state of the mouse 5-HT3R and an agonist-bound-like state of human 5-HT3R, in line with the functional profile of the drug. We report four human 5-HT3R structures and show that the human receptor transmembrane domain is intrinsically fragile. We also explain the lack of recovery after VTX administration via a membrane partition mechanism.
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Antidepressivos , Microscopia Crioeletrônica , Receptores 5-HT3 de Serotonina , Vortioxetina , Vortioxetina/farmacologia , Vortioxetina/química , Humanos , Receptores 5-HT3 de Serotonina/metabolismo , Receptores 5-HT3 de Serotonina/química , Animais , Camundongos , Antidepressivos/farmacologia , Antidepressivos/química , Piperazinas/farmacologia , Piperazinas/química , Sulfetos/química , Sulfetos/farmacologia , Simulação de Dinâmica Molecular , Células HEK293RESUMO
Animals use a small number of morphogens to pattern tissues, but it is unclear how evolution modulates morphogen signaling range to match tissues of varying sizes. Here, we used single molecule imaging in reconstituted morphogen gradients and in tissue explants to determine that Hedgehog diffused extra-cellularly as a monomer, and rapidly transitioned between membrane-confined and -unconfined states. Unexpectedly, the vertebrate-specific protein SCUBE1 expanded Hedgehog gradients by accelerating the transition rates between states without affecting the relative abundance of molecules in each state. This observation could not be explained under existing models of morphogen diffusion. Instead, we developed a topology-limited diffusion model in which cell-cell gaps create diffusion barriers, and morphogens can only overcome the barrier by passing through a membrane-unconfined state. Under this model, SCUBE1 promotes Hedgehog secretion and diffusion by allowing it to transiently overcome diffusion barriers. This multiscale understanding of morphogen gradient formation unified prior models and discovered novel knobs that nature can use to tune morphogen gradient sizes across tissues and organisms.
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Ceratocystis fimbriata, the causal agent of sweetpotato black rot, is a pathogen capable of developing and spreading within postharvest settings. A survey of North Carolina sweetpotato storage facilities was conducted to determine the arthropods present and identify potential vectors of C. fimbriata. Sixteen taxonomic categories were recovered, and the genus Drosophila (Diptera: Drosophilidae) accounted for 79% of individuals sampled, with Drosophila hydei being the most abundant species. Behavioral assays were conducted to determine if D. hydei is attracted to C. fimbriata-inoculated roots and if the pathogen could be recovered from external or internal surfaces of the insect. Flies were released in insect-trapping pitchers containing either C. fimbriata-inoculated or noninoculated roots or Petri dishes. No significant differences in fly number were detected in sweetpotato-baited pitchers; however, significant differences were found in the pitcher baited with a mature C. fimbriata culture. Flies were subjected to washes to determine if viable C. fimbriata was present (internally or externally); washes were plated onto carrot agar plates and observed for the presence of C. fimbriata colonies. Both external and internal washes had viable C. fimbriata inocula with no significant differences, and inoculated sweetpotatoes had a significantly higher number of flies carrying C. fimbriata. This study suggests that D. hydei can carry C. fimbriata from infected sweetpotatoes and move viable C. fimbriata inocula both externally and internally, making this the first report of any Drosophila sp. serving as a potential vector for the Ceratocystis genus.
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Drosophila , Insetos Vetores , Ipomoea batatas , Doenças das Plantas , Animais , Ipomoea batatas/microbiologia , Doenças das Plantas/microbiologia , Drosophila/microbiologia , Insetos Vetores/microbiologia , North Carolina , Ascomicetos/fisiologia , Raízes de Plantas/microbiologiaRESUMO
BACKGROUND: Non-steroidal anti-inflammatory drugs (NSAIDs) are commonly recommended for perioperative opioid-sparing multimodal analgesic treatments. Concerns regarding the potential for serious adverse events (SAEs) associated with perioperative NSAID treatment are especially relevant following gastrointestinal surgery. We assessed the risks of SAEs with perioperative NSAID treatment in patients undergoing gastrointestinal surgery. METHODS: We conducted a systematic review of randomised clinical trials assessing the harmful effects of NSAIDs versus placebo, usual care or no intervention in patients undergoing gastrointestinal surgery. The primary outcome was an incidence of SAEs. We systematically searched for eligible trials in five major databases up to January 2024. We performed risk of bias assessments to account for systematic errors, trial sequential analysis (TSA) to account for the risks of random errors, performed meta-analyses using R and used the Grading of Recommendations Assessment, Development and Evaluation framework to describe the certainty of evidence. RESULTS: We included 22 trials enrolling 1622 patients for our primary analyses. Most trials were at high risk of bias. Meta-analyses (risk ratio 0.78; 95% confidence interval [CI] 0.51-1.19; I2 = 4%; p = .24; very low certainty of evidence) and TSA indicated a lack of information on the effects of NSAIDs compared to placebo on the risks of SAEs. Post-hoc beta-binomial regression sensitivity analyses including trials with zero events showed a reduction in SAEs with NSAIDs versus placebo (odds ratio 0.73; CI 0.54-0.99; p = .042). CONCLUSION: In adult patients undergoing gastrointestinal surgery, there was insufficient information to draw firm conclusions on the effects of NSAIDs on SAEs. The certainty of the evidence was very low.
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Anti-Inflamatórios não Esteroides , Procedimentos Cirúrgicos do Sistema Digestório , Humanos , Anti-Inflamatórios não Esteroides/efeitos adversos , Anti-Inflamatórios não Esteroides/uso terapêutico , Procedimentos Cirúrgicos do Sistema Digestório/efeitos adversos , Ensaios Clínicos Controlados Aleatórios como Assunto , Dor Pós-Operatória/tratamento farmacológico , Complicações Pós-Operatórias/induzido quimicamente , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/prevenção & controleRESUMO
Genomic selection, the application of genomic prediction (GP) models to select candidate individuals, has significantly advanced in the past two decades, effectively accelerating genetic gains in plant breeding. This article provides a holistic overview of key factors that have influenced GP in plant breeding during this period. We delved into the pivotal roles of training population size and genetic diversity, and their relationship with the breeding population, in determining GP accuracy. Special emphasis was placed on optimizing training population size. We explored its benefits and the associated diminishing returns beyond an optimum size. This was done while considering the balance between resource allocation and maximizing prediction accuracy through current optimization algorithms. The density and distribution of single-nucleotide polymorphisms, level of linkage disequilibrium, genetic complexity, trait heritability, statistical machine-learning methods, and non-additive effects are the other vital factors. Using wheat, maize, and potato as examples, we summarize the effect of these factors on the accuracy of GP for various traits. The search for high accuracy in GP-theoretically reaching one when using the Pearson's correlation as a metric-is an active research area as yet far from optimal for various traits. We hypothesize that with ultra-high sizes of genotypic and phenotypic datasets, effective training population optimization methods and support from other omics approaches (transcriptomics, metabolomics and proteomics) coupled with deep-learning algorithms could overcome the boundaries of current limitations to achieve the highest possible prediction accuracy, making genomic selection an effective tool in plant breeding.
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Genoma de Planta , Melhoramento Vegetal , Humanos , Genoma de Planta/genética , Seleção Genética , Genômica , Fenótipo , Genótipo , Plantas , Polimorfismo de Nucleotídeo Único/genéticaRESUMO
Heart disease in birds contributes to premature death and is usually detected postmortem. Echocardiography is a sensitive and noninvasive diagnostic modality but reported standard values for many species of birds, including American flamingos (Phoenicopterus ruber), are unavailable. Echocardiography was opportunistically performed on 30 unsedated American flamingos during their annual routine health examination. Structural heart disease was not found in any of the examined birds. However, 18 birds showed varying degrees of dynamic intraventricular obstruction. Echocardiographic parameters are reported. Benign neurocardiogenic weakness or syncopal events during handling were suspected in three birds. Stress combined with an intraventricular obstruction is believed to have triggered a cascade of parasympathetic innervation and sympathetic inhibition, similar to neurally mediated reflex syncope in humans.
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Aves , Síncope , Animais , Síncope/veterináriaRESUMO
Enhancer-gene communication is dependent on topologically associating domains (TADs) and boundaries enforced by the CCCTC-binding factor (CTCF) insulator, but the underlying structures and mechanisms remain controversial. Here, we investigate a boundary that typically insulates fibroblast growth factor (FGF) oncogenes but is disrupted by DNA hypermethylation in gastrointestinal stromal tumors (GISTs). The boundary contains an array of CTCF sites that enforce adjacent TADs, one containing FGF genes and the other containing ANO1 and its putative enhancers, which are specifically active in GIST and its likely cell of origin. We show that coordinate disruption of four CTCF motifs in the boundary fuses the adjacent TADs, allows the ANO1 enhancer to contact FGF3, and causes its robust induction. High-resolution micro-C maps reveal specific contact between transcription initiation sites in the ANO1 enhancer and FGF3 promoter that quantitatively scales with FGF3 induction such that modest changes in contact frequency result in strong changes in expression, consistent with a causal relationship.
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Cromatina , Elementos Facilitadores Genéticos , Fator de Ligação a CCCTC/genética , Fator de Ligação a CCCTC/metabolismo , Cromatina/genética , Oncogenes , DNA/químicaRESUMO
OBJECTIVE: This study aimed to compare the prevalence and incidence of polyautoimmunity between anticyclic citrullinated peptide antibody (anti-CCP)-positive and anti-CCP-negative patients with rheumatoid arthritis (RA). METHODS: In a nationwide register-based cohort study, patients with RA (disease duration ≤ 2 yrs) in the DANBIO rheumatology register with an available anti-CCP test in the Register of Laboratory Results for Research were identified. The polyautoimmunity outcome included 21 nonrheumatic autoimmune diseases identified by linkage between the Danish Patient Registry and Prescription Registry. The age- and sex-adjusted prevalence ratio (PR) was calculated by modified Poisson regression to estimate the prevalence at diagnosis in anti-CCP-positive vs anti-CCP-negative patients. The hazard ratio (HR) of polyautoimmunity within 5 years of entry into DANBIO was estimated in cause-specific Cox regression models. RESULTS: The study included 5839 anti-CCP-positive and 3799 anti-CCP-negative patients with RA. At first visit, the prevalence of prespecified polyautoimmune diseases in the Danish registers was 11.1% and 11.9% in anti-CCP-positive and anti-CCP-negative patients, respectively (PR 0.93, 95% CI 0.84-1.05). The most frequent autoimmune diseases were autoimmune thyroid disease, inflammatory bowel disease, and type 1 diabetes mellitus. During a mean follow-up of 3.5 years, only a few (n = 210) patients developed polyautoimmunity (HR 0.6, 95% CI 0.46-0.79). CONCLUSION: Polyautoimmunity as captured through the Danish National Patient Registry occurred in approximately 1 in 10 patients with RA at time of diagnosis regardless of anti-CCP status. In the years subsequent to the RA diagnosis, only a few and mainly anti-CCP-negative patients developed autoimmune disease.
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Anticorpos Antiproteína Citrulinada , Artrite Reumatoide , Humanos , Estudos de Coortes , Artrite Reumatoide/diagnóstico , Artrite Reumatoide/epidemiologia , Autoanticorpos , Dinamarca/epidemiologia , Peptídeos , Peptídeos CíclicosRESUMO
Although only a fraction of CTCF motifs are bound in any cell type, and approximately half of the occupied sites overlap cohesin, the mechanisms underlying cell-type specific attachment and ability to function as a chromatin organizer remain unknown. To investigate the relationship between CTCF and chromatin we applied a combination of imaging, structural and molecular approaches, using a series of brain and cancer associated CTCF mutations that act as CTCF perturbations. We demonstrate that binding and the functional impact of WT and mutant CTCF depend not only on the unique properties of each protein, but also on the genomic context of bound sites. Our studies also highlight the reciprocal relationship between CTCF and chromatin, demonstrating that the unique binding properties of WT and mutant proteins have a distinct impact on accessibility, TF binding, cohesin overlap, chromatin interactivity and gene expression programs, providing insight into their cancer and brain related effects.