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Freiwald WA
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The neural mechanisms of face processing: cells, areas, networks, and models

CURRENT OPINION IN NEUROBIOLOGY 2020 FEB; 60(?):184-191
Since its discovery, the face-processing network in the brain of the macaque monkey has emerged as a model system that allowed for major neural mechanisms of face recognition to be identified - with implications for object recognition at large. Populations of face cells encode faces through broad tuning curves, whose shapes change over time. Face representations differ qualitatively across faces areas, and we not only understand the global organization of these specializations, but also some of the transformations between face areas, both feed-forward and feed-back, and the computational principles behind face representations and transformations. Facial information is combined with physical features and mnemonic features in extensions of the core network, which forms an early part of the primate social brain.
Paller AS, Bansal A, Simpson EL, Boguniewicz M, Blauvelt A, Siegfried EC, Guttman-Yassky E, Hultsch T, Chen Z, Mina-Osorio P, Lu YF, Rossi AB, He XY, Kamal M, Graham NMH, Pirozzi G, Ruddy M, Eckert L, Gadkari A
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Clinically Meaningful Responses to Dupilumab in Adolescents with Uncontrolled Moderate-to-Severe Atopic Dermatitis: Post-hoc Analyses from a Randomized Clinical Trial

AMERICAN JOURNAL OF CLINICAL DERMATOLOGY 2020 FEB; 21(1):119-131
BackgroundAtopic dermatitis is a chronic inflammatory condition with substantial burden and limited treatment options for adolescents with moderate-to-severe disease. Significantly more patients treated with dupilumab vs. placebo achieved Investigator's Global Assessment 0/1 at week 16.ObjectiveThe objective of this study was to assess the impact of dupilumab treatment vs. placebo on the achievement of clinically meaningful improvements in atopic dermatitis signs, symptoms and quality of life.MethodsR668-AD-1526 LIBERTY AD ADOL was a randomized, double-blinded, parallel-group, phase III clinical trial. Two hundred and fifty-one adolescents with moderate-to-severe atopic dermatitis received dupilumab 300 mg every 4 weeks (q4w; n=84), dupilumab 200 or 300 mg every 2 weeks (q2w; n=82), or placebo (n=85). A post-hoc subgroup analysis was performed on 214 patients with Investigator's Global Assessment >1 at week 16. Measures of atopic dermatitis signs, symptoms, and quality of life were assessed. Clinically meaningful improvement in one or more of three domains of signs, symptoms, and quality of life was defined as an improvement of >= 50% in Eczema Area and Severity Index, >= 3 points in Peak Pruritus Numerical Rating Scale, or >= 6 points in the Children's Dermatology Life Quality Index from baseline.ResultsOf patients receiving dupilumab q2w, 80.5% [66/82] experienced clinically meaningful improvements in atopic dermatitis signs, symptoms, or quality of life at week 16 (vs. placebo, 20/85 [23.5%], difference 57.0% [95% confidence interval 44.5-69.4]; q4w vs. placebo, 53/84 [63.1%], difference 39.6% [95% confidence interval 25.9-53.3]; both p<0.0001). Results were similar in adolescents with Investigator's Global Assessment >1 at week 16 (q2w, 46/62 [74.2%] vs. placebo, 18/83 [21.7%], difference 52.5% [95% confidence interval 38.5-66.6]; q4w, 38/69 [55.1%] vs. placebo, difference 33.4% [95% confidence interval 18.7-48.1]; both p<0.0001).ConclusionsDupilumab provided clinically meaningful improvements in signs, symptoms, and quality of life in adolescents with moderate-to-severe atopic dermatitis among patients with Investigator's Global Assessment >1 at week 16. Treatment responses should be interpreted in the context of such clinically relevant patient-reported outcome measures.
Mong EF, Yang Y, Akat KM, Canfield J, VanWye J, Lockhart J, Tsibris JCM, Schatz F, Lockwood CJ, Tuschl T, Kayisli UA, Totary-Jain H
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Chromosome 19 microRNA cluster enhances cell reprogramming by inhibiting epithelial-to-mesenchymal transition

SCIENTIFIC REPORTS 2020 FEB 20; 10(1):? Article 3029
During implantation, cytotrophoblasts undergo epithelial-to-mesenchymal transition (EMT) as they differentiate into invasive extravillous trophoblasts (EVTs). The primate-specific microRNA cluster on chromosome 19 (C19MC) is exclusively expressed in the placenta, embryonic stem cells and certain cancers however, its role in EMT gene regulation is unknown. In situ hybridization for miR-517a/c, a C19MC cistron microRNA, in first trimester human placentas displayed strong expression in villous trophoblasts and a gradual decrease from proximal to distal cell columns as cytotrophoblasts differentiate into invasive EVTs. To investigate the role of C19MC in the regulation of EMT genes, we employed the CRISPR/dCas9 Synergistic Activation Mediator (SAM) system, which induced robust transcriptional activation of the entire C19MC cistron and resulted in suppression of EMT associated genes. Exposure of human iPSCs to hypoxia or differentiation of iPSCs into either cytotrophoblast-stem-like cells or EVT-like cells under hypoxia reduced C19MC expression and increased EMT genes. Furthermore, transcriptional activation of the C19MC cistron induced the expression of OCT4 and FGF4 and accelerated cellular reprogramming. This study establishes the CRISPR/dCas9 SAM as a powerful tool that enables activation of the entire C19MC cistron and uncovers its novel role in suppressing EMT genes critical for maintaining the epithelial cytotrophoblasts stem cell phenotype.
Ardeljan D, Steranka JP, Liu CH, Li Z, Taylor MS, Payer LM, Gorbounov M, Sarnecki JS, Deshpande V, Hruban RH, Boeke JD, Feny D, Wu PH, Smogorzewska A, Holland AJ, Burns KH
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Cell fitness screens reveal a conflict between LINE-1 retrotransposition and DNA replication

NATURE STRUCTURAL & MOLECULAR BIOLOGY 2020 FEB; 27(2):168-178
LINE-1 retrotransposon overexpression is a hallmark of human cancers. We identified a colorectal cancer wherein a fast-growing tumor subclone downregulated LINE-1, prompting us to examine how LINE-1 expression affects cell growth. We find that nontransformed cells undergo a TP53-dependent growth arrest and activate interferon signaling in response to LINE-1. TP53 inhibition allows LINE-1(+) cells to grow, and genome-wide-knockout screens show that these cells require replication-coupled DNA-repair pathways, replication-stress signaling and replication-fork restart factors. Our findings demonstrate that LINE-1 expression creates specific molecular vulnerabilities and reveal a retrotransposition-replication conflict that may be an important determinant of cancer growth. Knockout screens to assess the effect of LINE-1 expression on cell growth show that TP53-deficient cells require replication-stress signaling and replication-fork restart factors to suppress LINE-1 toxicity, and that LINE-1 expression activates the Fanconi anemia pathway, suggesting that retrotransposition conflicts with DNA replication.
Jouanguy E, Beziat V, Mogensen TH, Casanova JL, Tangye SG, Zhang SY
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Human inborn errors of immunity to herpes viruses

CURRENT OPINION IN IMMUNOLOGY 2020 FEB; 62(?):106-122
Infections with any of the nine human herpes viruses (HHV) can be asymptomatic or life-threatening. The study of patients with severe diseases caused by HHVs, in the absence of overt acquired immunodeficiency, has led to the discovery or diagnosis of various inborn errors of immunity. The related inborn errors of adaptive immunity disrupt alpha/beta T-cell rather than B-cell immunity. Affected patients typically develop HHV infections in the context of other infectious diseases. However, this is not always the case, as illustrated by inborn errors of SAP-dependent T-cell immunity to EBV-infected B cells. The related inborn errors of innate immunity disrupt leukocytes other than T and B cells, non-hematopoietic cells, or both. Patients typically develop only a single type of infection due to HHV, although, again, this is not always the case, as illustrated by inborn errors of TLR3 immunity resulting in HSV 1 encephalitis in some patients and influenza pneumonitis in others. Most severe HHV infections in otherwise healthy patients remains unexplained. The forward human genetic dissection of isolated and syndromic HHV-driven illnesses will establish the molecular and cellular basis of protective immunity to HHVs, paving the way for novel diagnosis and management strategies.
Dewhurst SM
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Chromothripsis and telomere crisis: engines of genome instability

CURRENT OPINION IN GENETICS & DEVELOPMENT 2020 FEB; 60(?):41-47
In the early stages of carcinogenesis cells confront two key suppressive checkpoints; senescence and telomere crisis. Telomere crisis is characterized by massive chromosomal instability and cell death. The genetic instability initiated during crisis leaves detectable scars on cancer genomes, the full scope of which is only just beginning to be appreciated. In particular, the dramatic genome reshuffling phenomenon chromothripsis has been mechanistically linked to the resolution of DNA bridges formed by dicentric chromosomes, and by the shattering of DNA inside micronuclei. Furthermore, an intriguing connection to innate immune signaling has begun to position telomere crisis as a crucial stage not only in the evolution of the cancer genome, but also in the interaction between the genome and the immune system.
The mu-opioid receptors (MOR, OPRM1) mediate the effects of beta-endorphin and modulate many biological functions including reward processing and addiction. The present study aimed to use bioinformatics to determine OPRM1 brain expression profiles in higher primates and to look for regulatory mechanisms. We used the same computational pipeline to analyze publicly available expression data from postmortem brain regions across humans, chimpanzees, and rhesus macaques. The most intriguing finding was high OPRM1 cerebellar expression in humans and chimpanzees and low expression in macaques. Together with previous reports of low cerebellar OPRM1 expression in mice, this suggests an evolutionary shift in the expression profiles. Bioinformatic analysis of the OPRM1 upstream region revealed a functional CTCF-binding region that evolved from tandem insertions of retrotransposons L1P1 and L1PA1 upstream (-60 kb) of OPRM1. The insertions arose in different time points after the split of small apes from great apes, and their combined sequence is unique. Furthermore, the derived G allele of SNP rs12191876, in the inserted region, is associated with an increased OPRM1 expression in the cerebellum of postmortem human brains (p = 4.7e-5). The derived G allele became the major allele (60-90%) in the populations represented in the 1000 Genomes Project and may be beneficial. This study provides a foundation for building new knowledge about evolutionary differences in OPRM1 brain expression. Further investigations are needed to elucidate the role of the inserted region and its SNPs in OPRM1 expression, and to assess the biological function and relevance of OPRM1 expression in the cerebellum.
Simaan H, Shalaby S, Hatoel M, Karinski O, Goldshmidt-Tran O, Horwitz BA
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The AP-1-like transcription factor ChAP1 balances tolerance and cell death in the response of the maize pathogen Cochliobolus heterostrophus to a plant phenolic

CURRENT GENETICS 2020 FEB; 66(1):187-203
Fungal pathogens need to contend with stresses including oxidants and antimicrobial chemicals resulting from host defenses. ChAP1 of Cochliobolus heterostrophus, agent of Southern corn leaf blight, encodes an ortholog of yeast YAP1. ChAP1 is retained in the nucleus in response to plant-derived phenolic acids, in addition to its well-studied activation by oxidants. Here, we used transcriptome profiling to ask which genes are regulated in response to ChAP1 activation by ferulic acid (FA), a phenolic abundant in the maize host. Nuclearization of ChAP1 in response to phenolics is not followed by strong expression of genes needed for oxidative stress tolerance. We, therefore, compared the transcriptomes of the wild-type pathogen and a ChAP1 deletion mutant, to study the function of ChAP1 in response to FA. We hypothesized that if ChAP1 is retained in the nucleus under plant-related stress conditions yet in the absence of obvious oxidant stress, it should have additional regulatory functions. The transcriptional signature in response to FA in the wild type compared to the mutant sheds light on the signaling mechanisms and response pathways by which ChAP1 can mediate tolerance to ferulic acid, distinct from its previously known role in the antioxidant response. The ChAP1-dependent FA regulon consists mainly of two large clusters. The enrichment of transport and metabolism-related genes in cluster 1 indicates that C. heterostrophus degrades FA and removes it from the cell. When this fails at increasing stress levels, FA provides a signal for cell death, indicated by the enrichment of cell death-related genes in cluster 2. By quantitation of survival and by TUNEL assays, we show that ChAP1 promotes survival and mitigates cell death. Growth rate data show a time window in which the mutant colony expands faster than the wild type. The results delineate a transcriptional regulatory pattern in which ChAP1 helps balance a survival response for tolerance to FA, against a pathway promoting cell death in the pathogen. A general model for the transition from a phase where the return to homeostasis dominates to a phase leading to the onset of cell death provides a context for understanding these findings.
Zhang YX, Sun YD, Shi YS, Walz T, Tong L
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Structural Insights into the Human Pre-mRNA 3 '-End Processing Machinery

MOLECULAR CELL 2020 FEB 20; 77(4):800-809.e6
The mammalian pre-mRNA 3'-end-processing machinery consists of cleavage and polyadenylation specificity factor (CPSF), cleavage stimulation factor (CstF), and other proteins, but the overall architecture of this machinery remains unclear. CPSF contains two functionally distinct modules: a cleavage factor (mCF) and a polyadenylation specificity factor (mPSF). Here, we have produced recombinant human CPSF and CstF and examined these factors by electron microscopy (EM). We find that mPSF is the organizational core of the machinery, while the conformations of mCF and CstF and the position of mCF relative to mPSF are highly variable. We have identified by cryo-EM a segment in CPSF100 that tethers mCF to mPSF, and we have named it the PSF interaction motif (PIM). Mutations in the PIM can abolish CPSF formation, indicating that it is a crucial contact in CPSF. We have also obtained reconstructions of mCF and CstF77 by cryo-EM, assembled around the mPSF core.
Kirst C, Skriabine S, Vieites-Prado A, Topilko T, Bertin P, Gerschenfeld G, Verny F, Topilko P, Michalski N, Tessier-Lavigne M, Renier N
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Mapping the Fine-Scale Organization and Plasticity of the Brain Vasculature

CELL 2020 FEB 20; 180(4):780-795.e25
The cerebral vasculature is a dense network of arteries, capillaries, and veins. Quantifying variations of the vascular organization across individuals, brain regions, or disease models is challenging. We used immunolabeling and tissue clearing to image the vascular network of adult mouse brains and developed a pipeline to segment terabyte-sized multi-channel images from light sheet microscopy, enabling the construction, analysis, and visualization of vascular graphs composed of over 100 million vessel segments. We generated datasets from over 20 mouse brains, with labeled arteries, veins, and capillaries according to their anatomical regions. We characterized the organization of the vascular network across brain regions, highlighting local adaptations and functional correlates. We propose a classification of cortical regions based on the vascular topology. Finally, we analysed brain-wide rearrangements of the vasculature in animal models of congenital deafness and ischemic stroke, revealing that vascular plasticity and remodeling adopt diverging rules in different models.