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Variation in the non-coding genome is being increasingly recognized to be involved in monogenic disease etiology. However, the interpretation of non-coding variation is complicated by a lack of understanding of how non-coding genetic elements function. Additional lines of evidence are therefore needed to recognize non-coding variants as pathogenic. We here present a case where a collective body of evidence resulted in the identification and conclusive classification of a pathogenic deep intronic variant in ATRX. This report demonstrates the utility of a multi-platform approach in aiding the identification of pathogenic variants outside coding regions. Furthermore, it marks the first reported instance of a deep intronic pathogenic variant in ATRX.
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Intrones , Proteína Nuclear Ligada al Cromosoma X , Humanos , Proteína Nuclear Ligada al Cromosoma X/genética , Masculino , Mutación , Discapacidad Intelectual Ligada al Cromosoma X/genética , Discapacidad Intelectual Ligada al Cromosoma X/patología , Discapacidad Intelectual Ligada al Cromosoma X/diagnósticoRESUMEN
OBJECTIVE: SCN1A variants are associated with epilepsy syndromes ranging from mild genetic epilepsy with febrile seizures plus (GEFS+) to severe Dravet syndrome (DS). Many variants are de novo, making early phenotype prediction difficult, and genotype-phenotype associations remain poorly understood. METHODS: We assessed data from a retrospective cohort of 1018 individuals with SCN1A-related epilepsies. We explored relationships between variant characteristics (position, in silico prediction scores: Combined Annotation Dependent Depletion (CADD), Rare Exome Variant Ensemble Learner (REVEL), SCN1A genetic score), seizure characteristics, and epilepsy phenotype. RESULTS: DS had earlier seizure onset than other GEFS+ phenotypes (5.3 vs. 12.0 months, p < .001). In silico variant scores were higher in DS versus GEFS+ (p < .001). Patients with missense variants in functionally important regions (conserved N-terminus, S4-S6) exhibited earlier seizure onset (6.0 vs. 7.0 months, p = .003) and were more likely to have DS (280/340); those with missense variants in nonconserved regions had later onset (10.0 vs. 7.0 months, p = .036) and were more likely to have GEFS+ (15/29, χ2 = 19.16, p < .001). A minority of protein-truncating variants were associated with GEFS+ (10/393) and more likely to be located in the proximal first and last exon coding regions than elsewhere in the gene (9.7% vs. 1.0%, p < .001). Carriers of the same missense variant exhibited less variability in age at seizure onset compared with carriers of different missense variants for both DS (1.9 vs. 2.9 months, p = .001) and GEFS+ (8.0 vs. 11.0 months, p = .043). Status epilepticus as presenting seizure type is a highly specific (95.2%) but nonsensitive (32.7%) feature of DS. SIGNIFICANCE: Understanding genotype-phenotype associations in SCN1A-related epilepsies is critical for early diagnosis and management. We demonstrate an earlier disease onset in patients with missense variants in important functional regions, the occurrence of GEFS+ truncating variants, and the value of in silico prediction scores. Status epilepticus as initial seizure type is a highly specific, but not sensitive, early feature of DS.
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Epilepsias Mioclónicas , Epilepsia , Convulsiones Febriles , Estado Epiléptico , Humanos , Estudios Retrospectivos , Canal de Sodio Activado por Voltaje NAV1.1/genética , Epilepsia/genética , Epilepsia/diagnóstico , Epilepsias Mioclónicas/genética , Convulsiones Febriles/genética , Fenotipo , Estudios de Asociación Genética , Mutación/genéticaRESUMEN
Our recent investigations indicated that isoforms of ferredoxin (Fd) and ferredoxin NADP+ reductase (FNR) play essential roles for the reductive steps of the 2C-methyl-D-erythritol 4-phosphate (MEP) pathway of terpenoid biosynthesis in peppermint glandular trichomes (GTs). Based on an analysis of several transcriptome data sets, we demonstrated the presence of transcripts for a leaf-type FNR (L-FNR), a leaf-type Fd (Fd I), a root-type FNR (R-FNR), and two root-type Fds (Fd II and Fd III) in several members of the mint family (Lamiaceae). The present study reports on the biochemical characterization of all Fd and FNR isoforms of peppermint (Mentha × piperita L.). The redox potentials of Fd and FNR isoforms were determined using photoreduction methods. Based on a diaphorase assay, peppermint R-FNR had a substantially higher specificity constant (kcat/Km) for NADPH than L-FNR. Similar results were obtained with ferricyanide as an electron acceptor. When assayed for NADPH-cytochrome c reductase activity, the specificity constant with the Fd II and Fd III isoforms (when compared to Fd I) was slightly higher for L-FNR and substantially higher for R-FNR. Based on real-time quantitative PCR assays with samples representing various peppermint organs and cell types, the Fd II gene was expressed very highly in metabolically active GTs (but also present at lower levels in roots), whereas Fd III was expressed at low levels in both roots and GTs. Our data provide evidence that high transcript levels of Fd II, and not differences in the biochemical properties of the encoded enzyme when compared to those of Fd III, are likely to support the formation of copious amounts of monoterpene via the MEP pathway in peppermint GTs. This work has laid the foundation for follow-up studies to further investigate the roles of a unique R-FNR-Fd II pair in non-photosynthetic GTs of the Lamiaceae.
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AIMS: This study aims to provide insight into sex-specific cardiovascular protein profiles and their associations with adverse outcomes, which may contribute to a better understanding of heart failure (HF) pathophysiology and the optimal use of circulating proteins for prognostication in women and men. METHODS AND RESULTS: In 250 stable patients with HF with reduced ejection fraction (HFrEF), we performed trimonthly blood sampling (median follow-up: 26 [17-30] months). We selected all baseline samples and two samples closest to the primary endpoint (PEP; composite of cardiovascular death, heart transplantation, left ventricular assist device implantation, and HF hospitalization) or one sample closest to censoring and applied the Olink Cardiovascular III panel. We used linear regression to study sex-based differences in baseline levels and joint models to study differences in the prognostic value of serially measured proteins. In 66 women and 184 men (mean age of 66 and 67 years, respectively), 21% and 28% reached the PEP, respectively. Mean baseline levels of fatty acid-binding protein 4, secretoglobin family 3A member 2, paraoxonase 3, and trefoil factor 3 were higher in women (Pinteraction : 0.001, 0.007, 0.018, and 0.049, respectively), while matrix metalloproteinase-3, interleukin 1 receptor-like 1, and myoglobin were higher in men (Pinteraction : <0.001, 0.001, and 0.049, respectively), independent of clinical characteristics. No significant differences between sexes were observed in the longitudinal associations of proteins with the PEP. Only peptidoglycan recognition protein 1 showed a suggestive interaction with sex for the primary outcome (Pinteraction = 0.028), without multiple testing correction, and was more strongly associated with adverse outcome in women {hazard ratio [HR] 3.03 [95% confidence interval (CI), 1.42 to 6.68], P = 0.008} compared with men [HR 1.18 (95% CI, 0.84 to 1.66), P = 0.347]. CONCLUSIONS: Although multiple cardiovascular-related proteins show sex differences at baseline, temporal associations with the adverse outcome do not differ between women and men with HFrEF.
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Sistema Cardiovascular , Insuficiencia Cardíaca , Disfunción Ventricular Izquierda , Humanos , Femenino , Masculino , Anciano , Volumen Sistólico/fisiología , PronósticoRESUMEN
PURPOSE: ARF1 was previously implicated in periventricular nodular heterotopia (PVNH) in only five individuals and systematic clinical characterisation was not available. The aim of this study is to provide a comprehensive description of the phenotypic and genotypic spectrum of ARF1-related neurodevelopmental disorder. METHODS: We collected detailed phenotypes of an international cohort of individuals (n=17) with ARF1 variants assembled through the GeneMatcher platform. Missense variants were structurally modelled, and the impact of several were functionally validated. RESULTS: De novo variants (10 missense, 1 frameshift, 1 splice altering resulting in 9 residues insertion) in ARF1 were identified among 17 unrelated individuals. Detailed phenotypes included intellectual disability (ID), microcephaly, seizures and PVNH. No specific facial characteristics were consistent across all cases, however microretrognathia was common. Various hearing and visual defects were recurrent, and interestingly, some inflammatory features were reported. MRI of the brain frequently showed abnormalities consistent with a neuronal migration disorder. CONCLUSION: We confirm the role of ARF1 in an autosomal dominant syndrome with a phenotypic spectrum including severe ID, microcephaly, seizures and PVNH due to impaired neuronal migration.
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Discapacidad Intelectual , Microcefalia , Heterotopia Nodular Periventricular , Humanos , Encéfalo/diagnóstico por imagen , Genotipo , Discapacidad Intelectual/genética , Fenotipo , Convulsiones/genéticaRESUMEN
Above-ground material of members of the mint family is commercially distilled to extract essential oils, which are then formulated into a myriad of consumer products. Most of the research aimed at characterizing the processes involved in the formation of terpenoid oil constituents has focused on leaves. We now demonstrate, by investigating three mint species, peppermint (Mentha Ë£ piperita L.), spearmint (Mentha spicata L.) and horsemint (Mentha longifolia (L.) Huds.; accessions CMEN 585 and CMEN 584), that other organs - namely stems, rhizomes and roots - also emit volatiles and that the terpenoid volatile composition of these organs can vary substantially from that of leaves, supporting the notion that substantial, currently underappreciated, chemical diversity exists. Differences in volatile quantities released by plants whose roots had been dipped in a Verticillium dahliae-spore suspension (experimental) or dipped in water (controls) were evident: increases of some volatiles in the root headspace of mint species that are susceptible to Verticillium wilt disease (peppermint and M. longifolia CMEN 584) were detected, while the quantities of certain volatiles decreased in rhizomes of species that show resistance to the disease (spearmint and M. longifolia CMEN 585). To address the genetic and biochemical basis underlying chemical diversity, we took advantage of the newly sequenced M. longifolia CMEN 585 genome to identify candidate genes putatively coding for monoterpene synthases (MTSs), the enzymes that catalyze the first committed step in the biosynthesis of monoterpenoid volatiles. The functions of these genes were established by heterologous expression in Escherichia coli, purification of the corresponding recombinant proteins, and enzyme assays, thereby establishing the existence of MTSs with activities to convert a common substrate, geranyl diphosphate, to (+)-α-terpineol, 1,8-cineole, γ-terpinene, and (-)-bornyl diphosphate, but were not active with other potential substrates. In conjunction with previously described MTSs that catalyze the formation of (-)-ß-pinene and (-)-limonene, the product profiles of the MTSs identified here can explain the generation of all major monoterpene skeletons represented in the volatiles released by different mint organs.
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Fear is an adaptive emotion that mobilizes defensive resources upon confrontation with danger. However, fear becomes maladaptive and can give rise to the development of clinical anxiety when it exceeds the degree of threat, generalizes broadly across stimuli and contexts, persists after the danger is gone or promotes excessive avoidance behaviour. Pavlovian fear conditioning has been the prime research instrument that has led to substantial progress in understanding the multi-faceted psychological and neurobiological mechanisms of fear in past decades. In this Perspective, we suggest that fruitful use of Pavlovian fear conditioning as a laboratory model of clinical anxiety requires moving beyond the study of fear acquisition to associated fear conditioning phenomena: fear extinction, generalization of conditioned fear and fearful avoidance. Understanding individual differences in each of these phenomena, not only in isolation but also in how they interact, will further strengthen the external validity of the fear conditioning model as a tool with which to study maladaptive fear as it manifests in clinical anxiety.
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This study examined the influence of pectinase-producing non-Saccharomyces yeasts on the chemical and sensory attributes of red and white wines with added pectin. Merlot and Chardonnay wines were produced with or without a mixture of pectinase-producing non-Saccharomyces yeasts (Cryptococcus adeliensis, Issatchenkia orientalis, and Pichia kluyveri) added to the must prior to alcoholic fermentation conducted by a commercial strain of Saccharomyces cerevisiae. To ensure sufficient substrate was present, varying concentrations of apple pectin (up to 1.25 g/L for red wines and 1.00 g/L for white wine) were added at the start of fermentation. After bottling, trained panelists (n = 10) analyzed these wines for aroma, flavor, taste, and mouthfeel attributes. For both wines, significant interactions were noted between the presence of non-Saccharomyces yeasts and pectin addition which affected pH, titratable acidity, and concentrations of D-galacturonic acid. While no significant sensory differences were observed among the red wines, limited changes were noted for white wines. However, a strong positive correlation was found between the D-galacturonic acid and buttery aroma for Chardonnay and with flavor for Merlot. Increasing D-galacturonic acid concentrations, through utilization of non-Saccharomyces yeasts, may improve the wine quality as a buttery aroma is often associated with high-quality Chardonnay. For both red and white wines, the utilization of these particular non-Saccharomyces yeasts significantly influenced chemical properties but yielded minor sensory changes without any faults. PRACTICAL APPLICATION: With the recent trend to reduce alcohol content in commercial wines, the interest in non-Saccharomyces yeasts has grown. This study showed that the addition of non-Saccharomyces yeasts, perhaps due to their pectinase activity, influenced the chemical characteristics of red and white wines with limited sensory differences, making these yeasts a useful tool for winemakers to modify wine properties.
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Vitis , Vino , Vino/análisis , Poligalacturonasa , Etanol/análisis , Levaduras , Fermentación , Saccharomyces cerevisiae , PectinasRESUMEN
BACKGROUND: This study aimed to identify heart failure (HF) subphenotypes using 92 repeatedly measured circulating proteins in 250 patients with heart failure with reduced ejection fraction, and to investigate their clinical characteristics and prognosis. METHODS: Clinical data and blood samples were collected tri-monthly until the primary endpoint (PEP) or censoring occurred, with a maximum of 11 visits. The Olink Cardiovascular III panel was measured in baseline samples and the last two samples before the PEP (in 66 PEP cases), or the last sample before censoring (in 184 PEP-free patients). The PEP comprised cardiovascular death, heart transplantation, Left Ventricular Assist Device implantation, and hospitalization for HF. Cluster analysis was performed on individual biomarker trajectories to identify subphenotypes. Then biomarker profiles and clinical characteristics were investigated, and survival analysis was conducted. RESULTS: Clustering revealed three clinically diverse subphenotypes. Cluster 3 was older, with a longer duration of, and more advanced HF, and most comorbidities. Cluster 2 showed increasing levels over time of most biomarkers. In cluster 3, there were elevated baseline levels and increasing levels over time of 16 remaining biomarkers. Median follow-up was 2.2 (1.4-2.5) years. Cluster 3 had a significantly poorer prognosis compared to cluster 1 (adjusted event-free survival time ratio 0.25 (95%CI:0.12-0.50), p < 0.001). Repeated measurements clusters showed incremental prognostic value compared to clusters using single measurements, or clinical characteristics only. CONCLUSIONS: Clustering based on repeated biomarker measurements revealed three clinically diverse subphenotypes, of which one has a significantly worse prognosis, therefore contributing to improved (individualized) prognostication.
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Insuficiencia Cardíaca , Trasplante de Corazón , Disfunción Ventricular Izquierda , Biomarcadores , Humanos , Pronóstico , Volumen Sistólico , Función Ventricular IzquierdaRESUMEN
Mentha longifolia (L.) Huds., a wild, diploid mint species, has been developed as a model for mint genetic and genomic research to aid breeding efforts that target Verticillium wilt disease resistance and essential oil monoterpene composition. Here, we present a near-complete, chromosome-scale mint genome assembly for M. longifolia USDA accession CMEN 585. This new assembly is an update of a previously published genome draft, with dramatic improvements. A total of 42,107 protein-coding genes were annotated and placed on 12 chromosomal scaffolds. One hundred fifty-three genes contained conserved sequence domains consistent with nucleotide binding site-leucine-rich-repeat plant disease resistance genes. Homologs of genes implicated in Verticillium wilt resistance in other plant species were also identified. Multiple paralogs of genes putatively involved in p-menthane monoterpenoid biosynthesis were identified and several cases of gene clustering documented. Heterologous expression of candidate genes, purification of recombinant target proteins, and subsequent enzyme assays allowed us to identify the genes underlying the pathway that leads to the most abundant monoterpenoid volatiles. The bioinformatic and functional analyses presented here are laying the groundwork for using marker-assisted selection in improving disease resistance and essential oil traits in mints.
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Mentha , Aceites Volátiles , Verticillium , Cromosomas , Resistencia a la Enfermedad/genética , Mentha/química , Mentha/genética , Mentha/metabolismo , Monoterpenos/análisis , Monoterpenos/metabolismo , Aceites Volátiles/metabolismo , Fitomejoramiento , Verticillium/genéticaRESUMEN
Three species of the genus Equisetum (E. arvense, E. hyemale, and E. telmateia) were selected for an analysis of chemical diversity in an ancient land plant lineage. Principal component analysis of metabolomics data obtained with above-ground shoot and below-ground rhizome extracts enabled a separation of all sample types, indicating species- and organ-specific patterns of metabolite accumulation. Follow-up efforts indicated that galactolipids, carotenoids, and flavonoid glycosides contributed positively to the separation of shoot samples, while stryrylpyrone glycosides and phenolic glycosides were the most prominent positive contributors to the separation of rhizome samples. Consistent with metabolite data, genes coding for enzymes of flavonoid and galactolipid biosynthesis were found to be expressed at elevated levels in shoot samples, whereas a putative styrylpyrone synthase gene was expressed preferentially in rhizomes. The current study builds a foundation for future endeavors to further interrogate the organ and tissue specificity of metabolism in the last living genus of a fern family that was prevalent in the forests of the late Paleozoic era.
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Transient receptor potential vanilloid 2 (TRPV2) is involved in many critical physiological and pathophysiological processes, making it a promising drug target. Here we present cryo-electron microscopy (cryo-EM) structures of rat TRPV2 in lipid nanodiscs activated by 2-aminoethoxydiphenyl borate (2-APB) and propose a TRPV2-specific 2-ABP binding site at the interface of S5 of one monomer and the S4-S5 linker of the adjacent monomer. In silico docking and electrophysiological studies confirm the key role of His521 and Arg539 in 2-APB activation of TRPV2. Additionally, electrophysiological experiments show that the combination of 2-APB and cannabidiol has a synergetic effect on TRPV2 activation, and cryo-EM structures demonstrate that both drugs were able to bind simultaneously. Together, our cryo-EM structures represent multiple functional states of the channel, providing a native picture of TRPV2 activation by small molecules and a structural framework for the development of TRPV2-specific activators.
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Canales Catiónicos TRPV , Animales , Sitios de Unión , Microscopía por Crioelectrón , Dominios Proteicos , Ratas , Canales Catiónicos TRPV/metabolismoRESUMEN
PURPOSE: Early detection and intervention of mental health problems in youth are topical given that mental disorders often start early in life. Young people with emerging mental disorders however, often present with non-specific, fluctuating symptoms. Recent reports indicate a decline in social functioning (SF) as an early sign of specific emerging mental disorders such as depression or anxiety, making SF a favorable transdiagnostic approach for earlier detection and intervention. Our aim was to investigate the value of SF in relation to transdiagnostic symptoms, and as a predictor of psychopathology over time, while exploring traditional retrospective versus innovative daily diary measurements of SF in youth. METHOD: Participants (N = 75) were 16-25 years of age and presented early stage psychiatric symptomatology. Psychiatric symptoms, including anxiety and depression, as well as SF -both in retrospect and in daily life- were assessed at two time points and analyzed cross-sectionally and longitudinally. RESULTS: A significant and negative association between SF and all psychiatric symptoms was found, and SF was a significant predictor of change in general psychiatric symptoms over time. Results were only significant when SF was measured traditionally retrospective. CONCLUSION: This study confirms a distinct relation between SF and transdiagnostic psychiatric symptoms in youth, even in a (sub)clinical population, and points towards SF as a predictor of transdiagnostic psychiatric symptoms. Further research is needed to learn more about the added value of daily life versus retrospective measurements.
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Salud Mental , Interacción Social , Adolescente , Ansiedad/psicología , Trastornos de Ansiedad , Humanos , Estudios RetrospectivosRESUMEN
BACKGROUND: A neurodevelopmental syndrome was recently reported in four patients with SOX4 heterozygous missense variants in the high-mobility-group (HMG) DNA-binding domain. The present study aimed to consolidate clinical and genetic knowledge of this syndrome. METHODS: We newly identified 17 patients with SOX4 variants, predicted variant pathogenicity using in silico tests and in vitro functional assays and analysed the patients' phenotypes. RESULTS: All variants were novel, distinct and heterozygous. Seven HMG-domain missense and five stop-gain variants were classified as pathogenic or likely pathogenic variant (L/PV) as they precluded SOX4 transcriptional activity in vitro. Five HMG-domain and non-HMG-domain missense variants were classified as of uncertain significance (VUS) due to negative results from functional tests. When known, inheritance was de novo or from a mosaic unaffected or non-mosaic affected parent for patients with L/PV, and from a non-mosaic asymptomatic or affected parent for patients with VUS. All patients had neurodevelopmental, neurological and dysmorphic features, and at least one cardiovascular, ophthalmological, musculoskeletal or other somatic anomaly. Patients with L/PV were overall more affected than patients with VUS. They resembled patients with other neurodevelopmental diseases, including the SOX11-related and Coffin-Siris (CSS) syndromes, but lacked the most specific features of CSS. CONCLUSION: These findings consolidate evidence of a fairly non-specific neurodevelopmental syndrome due to SOX4 haploinsufficiency in neurogenesis and multiple other developmental processes.
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Deformidades Congénitas de la Mano , Discapacidad Intelectual , Micrognatismo , Trastornos del Neurodesarrollo , Humanos , Micrognatismo/genética , Deformidades Congénitas de la Mano/genética , Discapacidad Intelectual/genética , Trastornos del Neurodesarrollo/genética , Síndrome , Fenotipo , ADN , Factores de Transcripción SOXC/genéticaRESUMEN
BACKGROUND AND OBJECTIVES: Pathogenic variants in the neuronal sodium channel α1 subunit gene (SCN1A) are the most frequent monogenic cause of epilepsy. Phenotypes comprise a wide clinical spectrum, including severe childhood epilepsy; Dravet syndrome, characterized by drug-resistant seizures, intellectual disability, and high mortality; and the milder genetic epilepsy with febrile seizures plus (GEFS+), characterized by normal cognition. Early recognition of a child's risk for developing Dravet syndrome vs GEFS+ is key for implementing disease-modifying therapies when available before cognitive impairment emerges. Our objective was to develop and validate a prediction model using clinical and genetic biomarkers for early diagnosis of SCN1A-related epilepsies. METHODS: We performed a retrospective multicenter cohort study comprising data from patients with SCN1A-positive Dravet syndrome and patients with GEFS+ consecutively referred for genetic testing (March 2001-June 2020) including age at seizure onset and a newly developed SCN1A genetic score. A training cohort was used to develop multiple prediction models that were validated using 2 independent blinded cohorts. Primary outcome was the discriminative accuracy of the model predicting Dravet syndrome vs other GEFS+ phenotypes. RESULTS: A total of 1,018 participants were included. The frequency of Dravet syndrome was 616/743 (83%) in the training cohort, 147/203 (72%) in validation cohort 1, and 60/72 (83%) in validation cohort 2. A high SCN1A genetic score (133.4 [SD 78.5] vs 52.0 [SD 57.5]; p < 0.001) and young age at onset (6.0 [SD 3.0] vs 14.8 [SD 11.8] months; p < 0.001) were each associated with Dravet syndrome vs GEFS+. A combined SCN1A genetic score and seizure onset model separated Dravet syndrome from GEFS+ more effectively (area under the curve [AUC] 0.89 [95% CI 0.86-0.92]) and outperformed all other models (AUC 0.79-0.85; p < 0.001). Model performance was replicated in both validation cohorts 1 (AUC 0.94 [95% CI 0.91-0.97]) and 2 (AUC 0.92 [95% CI 0.82-1.00]). DISCUSSION: The prediction model allows objective estimation at disease onset whether a child will develop Dravet syndrome vs GEFS+, assisting clinicians with prognostic counseling and decisions on early institution of precision therapies (http://scn1a-prediction-model.broadinstitute.org/). CLASSIFICATION OF EVIDENCE: This study provides Class II evidence that a combined SCN1A genetic score and seizure onset model distinguishes Dravet syndrome from other GEFS+ phenotypes.
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Epilepsias Mioclónicas , Epilepsia , Niño , Estudios de Cohortes , Diagnóstico Precoz , Epilepsias Mioclónicas/diagnóstico , Epilepsias Mioclónicas/genética , Epilepsia/diagnóstico , Epilepsia/genética , Humanos , Mutación , Canal de Sodio Activado por Voltaje NAV1.1/genética , Estudios RetrospectivosRESUMEN
Peppermint (Mentha x piperita L.) and Japanese catnip (Schizonepeta tenuifolia (Benth.) Briq.) accumulate p-menthane monoterpenoids with identical functionalization patterns but opposite stereochemistry. In the present study, we investigate the enantioselectivity of multiple enzymes involved in monoterpenoid biosynthesis in these species. Based on kinetic assays, mint limonene synthase, limonene 3-hydroxylase, isopiperitenol dehydrogenase, isopiperitenone reductase, and menthone reductase exhibited significant enantioselectivity toward intermediates of the pathway that proceeds through (-)-4S-limonene. Limonene synthase, isopiperitenol dehydrogenase and isopiperitenone reductase of Japanese catnip preferred intermediates of the pathway that involves (+)-4R-limonene, whereas limonene 3-hydroxylase was not enantioselective, and the activities of pulegone reductase and menthone reductase were too low to acquire meaningful kinetic data. Molecular modeling studies with docked ligands generally supported the experimental data obtained with peppermint enzymes, indicating that the preferred enantiomer was aligned well with the requisite cofactor and amino acid residues implicated in catalysis. A striking example for enantioselectivity was peppermint (-)-menthone reductase, which binds (-)-menthone with exquisite affinity but was predicted to bind (+)-menthone in a non-productive orientation that positions its carbonyl functional group at considerable distance to the NADPH cofactor. The work presented here lays the groundwork for structure-function studies aimed at unraveling how enantioselectivity evolved in closely related species of the Lamiaceae and beyond.
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Lamiaceae/enzimología , Mentha piperita/enzimología , Oxigenasas de Función Mixta/metabolismo , Monoterpenos/metabolismo , Oxidorreductasas/metabolismo , Estereoisomerismo , Estructura MolecularRESUMEN
Monoterpenoids are the main components of plant essential oils and the active components of some traditional Chinese medicinal herbs like Mentha haplocalyx Briq., Nepeta tenuifolia Briq., Perilla frutescens (L.) Britt and Pogostemin cablin (Blanco) Benth. Pulegone reductase is the key enzyme in the biosynthesis of menthol and is required for the stereoselective reduction of the Δ2,8 double bond of pulegone to produce the major intermediate menthone, thus determining the stereochemistry of menthol. However, the structural basis and mechanism underlying the stereoselectivity of pulegone reductase remain poorly understood. In this study, we characterized a novel (-)-pulegone reductase from Nepeta tenuifolia (NtPR), which can catalyze (-)-pulegone to (+)-menthone and (-)-isomenthone through our RNA-seq, bioinformatic analysis in combination with in vitro enzyme activity assay, and determined the structure of (+)-pulegone reductase from M. piperita (MpPR) by using X-ray crystallography, molecular modeling and docking, site-directed mutagenesis, molecular dynamics simulations, and biochemical analysis. We identified and validated the critical residues in the crystal structure of MpPR involved in the binding of the substrate pulegone. We also further identified that residues Leu56, Val282, and Val284 determine the stereoselectivity of the substrate pulegone, and mainly contributes to the product stereoselectivity. This work not only provides a starting point for the understanding of stereoselectivity of pulegone reductases, but also offers a basis for the engineering of menthone/menthol biosynthetic enzymes to achieve high-titer, industrial-scale production of enantiomerically pure products.
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Experimental Psychopathology (EPP) and the Research Domain Criteria (RDoC) are research approaches that have developed in parallel, providing inter-related yet different scientific frameworks to investigate psychopathology at the intersection of fundamental and applied research. Here we address the overlap and differences between RDoC and EPP, and the challenges that both approaches face. Although overlap between EPP and RDoC can be clearly observed, each approach has its own unique strengths and weaknesses. These aspects will be illustrated by examples with respect to fear conditioning, an experimental procedure that has played a central role in both EPP and RDoC. We see much potential in boosting psychopathology research by combining the strengths of these two approaches.
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Trastornos Mentales , Miedo , Humanos , Trastornos Mentales/diagnóstico , Modelos Teóricos , PsicopatologíaRESUMEN
Fear generalization to stimuli resembling a conditioned danger-cue (CS+) is a fundamental dynamic of classical fear-conditioning. Despite the ubiquity of fear generalization in human experience and its known pathogenic contribution to clinical anxiety, neural investigations of human generalization have only recently begun. The present work provides the first meta-analysis of this growing literature to delineate brain substrates of conditioned fear-generalization and formulate a working neural model. Included studies (K = 6, N = 176) reported whole-brain fMRI results and applied generalization-gradient methodology to identify brain activations that gradually strengthen (positive generalization) or weaken (negative generalization) as presented stimuli increase in CS+ resemblance. Positive generalization was instantiated in cingulo-opercular, frontoparietal, striatal-thalamic, and midbrain regions (locus coeruleus, periaqueductal grey, ventral tegmental area), while negative generalization was implemented in default-mode network nodes (ventromedial prefrontal cortex, hippocampus, middle temporal gyrus, angular gyrus) and amygdala. Findings are integrated within an updated neural account of generalization centering on the hippocampus, its modulation by locus coeruleus and basolateral amygdala, and the excitation of threat- or safety-related loci by the hippocampus.
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Mapeo Encefálico , Miedo , Encéfalo/diagnóstico por imagen , Condicionamiento Clásico , Generalización Psicológica , Humanos , Imagen por Resonancia MagnéticaRESUMEN
PURPOSE: Neurodevelopmental disorders (NDDs) encompass a spectrum of genetically heterogeneous disorders with features that commonly include developmental delay, intellectual disability, and autism spectrum disorders. We sought to delineate the molecular and phenotypic spectrum of a novel neurodevelopmental disorder caused by variants in the GNAI1 gene. METHODS: Through large cohort trio-based exome sequencing and international data-sharing, we identified 24 unrelated individuals with NDD phenotypes and a variant in GNAI1, which encodes the inhibitory Gαi1 subunit of heterotrimeric G-proteins. We collected detailed genotype and phenotype information for each affected individual. RESULTS: We identified 16 unique variants in GNAI1 in 24 affected individuals; 23 occurred de novo and 1 was inherited from a mosaic parent. Most affected individuals have a severe neurodevelopmental disorder. Core features include global developmental delay, intellectual disability, hypotonia, and epilepsy. CONCLUSION: This collaboration establishes GNAI1 variants as a cause of NDDs. GNAI1-related NDD is most often characterized by severe to profound delays, hypotonia, epilepsy that ranges from self-limiting to intractable, behavior problems, and variable mild dysmorphic features.