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1.
Clin Genet ; 105(3): 294-301, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38044714

RESUMO

Calmodulin-binding transcriptional activator 1 (CAMTA1) is highly expressed in the brain and plays a role in cell cycle regulation, cell differentiation, regulation of long-term memory, and initial development, maturation, and survival of cerebellar neurons. The existence of human neurological phenotypes, including cerebellar dysfunction with variable cognitive and behavioral abnormalities (CECBA), associated with CAMTA1 variants, has further supported its role in brain functions. In this study, we phenotypically and molecularly characterize the largest cohort of individuals (n = 26) with 23 novel CAMTA1 variants (frameshift-7, nonsense-6, splicing-1, initiation codon-1, missense-5, and intragenic deletions-3) and compare the findings with all previously reported cases (total = 53). We show that the most notable phenotypic findings are developmental delay/intellectual disability, unsteady or uncoordinated gait, hypotonia, behavioral problems, and eye abnormalities. In addition, there is a high incidence of dysarthria, dysgraphia, microcephaly, gastrointestinal abnormalities, sleep difficulties, and nonspecific brain MRI findings; a few of which have been under-reported. More than one third of the variants in this cohort were inherited from an asymptomatic or mildly affected parent suggesting reduced penetrance and variable expressivity. Our cohort provides a comprehensive characterization of the spectrum of phenotypes and genotypes among individuals with CECBA and the large data will facilitate counseling and formulating management plans and surveillance recommendations for these individuals.


Assuntos
Deficiência Intelectual , Fatores de Transcrição , Humanos , Encéfalo/metabolismo , Proteínas de Ligação ao Cálcio/genética , Genótipo , Deficiência Intelectual/genética , Fenótipo , Transativadores/genética , Fatores de Transcrição/genética
2.
Biol Psychiatry ; 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-38061466

RESUMO

BACKGROUND: Individual variability in response to rewarding stimuli is a striking but understudied phenomenon. The mesolimbic dopamine system is critical in encoding the reinforcing properties of both natural reward and alcohol; however, how innate or baseline differences in the response dynamics of this circuit define individual behavior and shape future vulnerability to alcohol remain unknown. METHODS: Using naturalistic behavioral assays, a voluntary alcohol drinking paradigm, in vivo fiber photometry, in vivo electrophysiology, and chemogenetics, we investigated how differences in mesolimbic neural circuit activity contribute to the individual variability seen in reward processing and, by proxy, alcohol drinking. RESULTS: We first characterized heterogeneous behavioral and neural responses to natural reward and defined how these baseline responses predicted future individual alcohol-drinking phenotypes in male mice. We then determined spontaneous ventral tegmental area dopamine neuron firing profiles associated with responses to natural reward that predicted alcohol drinking. Using a dual chemogenetic approach, we mimicked specific mesolimbic dopamine neuron firing activity before or during voluntary alcohol drinking to link unique neurophysiological profiles to individual phenotype. We show that hyperdopaminergic individuals exhibit a lower neuronal response to both natural reward and alcohol that predicts lower levels of alcohol consumption in the future. CONCLUSIONS: These findings reveal unique, circuit-specific neural signatures that predict future individual vulnerability or resistance to alcohol and expand the current knowledge base on how some individuals are able to titrate their alcohol consumption whereas others go on to engage in unhealthy alcohol-drinking behaviors.

3.
J Natl Compr Canc Netw ; 21(8): 851-880, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37549914

RESUMO

This selection from the NCCN Guidelines for Adolescent and Young Adult (AYA) Oncology focuses on considerations for the comprehensive care of AYA patients with cancer. Compared with older adults with cancer, AYA patients have unique needs regarding treatment, fertility counseling, psychosocial and behavioral issues, and supportive care services. The complete version of the NCCN Guidelines for Adolescent and Young Adult (AYA) Oncology addresses additional aspects of caring for AYA patients, including risk factors, screening, diagnosis, and survivorship.


Assuntos
Oncologia , Neoplasias , Humanos , Adolescente , Adulto Jovem , Idoso , Neoplasias/diagnóstico , Neoplasias/terapia , Neoplasias/psicologia , Aconselhamento , Sobrevivência , Fatores de Risco
4.
JMIR Infodemiology ; 3: e40156, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37113378

RESUMO

Background: Despite increasing awareness about and advances in addressing social media misinformation, the free flow of false COVID-19 information has continued, affecting individuals' preventive behaviors, including masking, testing, and vaccine uptake. Objective: In this paper, we describe our multidisciplinary efforts with a specific focus on methods to (1) gather community needs, (2) develop interventions, and (3) conduct large-scale agile and rapid community assessments to examine and combat COVID-19 misinformation. Methods: We used the Intervention Mapping framework to perform community needs assessment and develop theory-informed interventions. To supplement these rapid and responsive efforts through large-scale online social listening, we developed a novel methodological framework, comprising qualitative inquiry, computational methods, and quantitative network models to analyze publicly available social media data sets to model content-specific misinformation dynamics and guide content tailoring efforts. As part of community needs assessment, we conducted 11 semistructured interviews, 4 listening sessions, and 3 focus groups with community scientists. Further, we used our data repository with 416,927 COVID-19 social media posts to gather information diffusion patterns through digital channels. Results: Our results from community needs assessment revealed the complex intertwining of personal, cultural, and social influences of misinformation on individual behaviors and engagement. Our social media interventions resulted in limited community engagement and indicated the need for consumer advocacy and influencer recruitment. The linking of theoretical constructs underlying health behaviors to COVID-19-related social media interactions through semantic and syntactic features using our computational models has revealed frequent interaction typologies in factual and misleading COVID-19 posts and indicated significant differences in network metrics such as degree. The performance of our deep learning classifiers was reasonable, with an F-measure of 0.80 for speech acts and 0.81 for behavior constructs. Conclusions: Our study highlights the strengths of community-based field studies and emphasizes the utility of large-scale social media data sets in enabling rapid intervention tailoring to adapt grassroots community interventions to thwart misinformation seeding and spread among minority communities. Implications for consumer advocacy, data governance, and industry incentives are discussed for the sustainable role of social media solutions in public health.

5.
Am J Hum Genet ; 110(2): 215-227, 2023 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-36586412

RESUMO

Neurodevelopmental disorders (NDDs) result from highly penetrant variation in hundreds of different genes, some of which have not yet been identified. Using the MatchMaker Exchange, we assembled a cohort of 27 individuals with rare, protein-altering variation in the transcriptional coregulator ZMYM3, located on the X chromosome. Most (n = 24) individuals were males, 17 of which have a maternally inherited variant; six individuals (4 male, 2 female) harbor de novo variants. Overlapping features included developmental delay, intellectual disability, behavioral abnormalities, and a specific facial gestalt in a subset of males. Variants in almost all individuals (n = 26) are missense, including six that recurrently affect two residues. Four unrelated probands were identified with inherited variation affecting Arg441, a site at which variation has been previously seen in NDD-affected siblings, and two individuals have de novo variation resulting in p.Arg1294Cys (c.3880C>T). All variants affect evolutionarily conserved sites, and most are predicted to damage protein structure or function. ZMYM3 is relatively intolerant to variation in the general population, is widely expressed across human tissues, and encodes a component of the KDM1A-RCOR1 chromatin-modifying complex. ChIP-seq experiments on one variant, p.Arg1274Trp, indicate dramatically reduced genomic occupancy, supporting a hypomorphic effect. While we are unable to perform statistical evaluations to definitively support a causative role for variation in ZMYM3, the totality of the evidence, including 27 affected individuals, recurrent variation at two codons, overlapping phenotypic features, protein-modeling data, evolutionary constraint, and experimentally confirmed functional effects strongly support ZMYM3 as an NDD-associated gene.


Assuntos
Deficiência Intelectual , Malformações do Sistema Nervoso , Transtornos do Neurodesenvolvimento , Humanos , Masculino , Feminino , Transtornos do Neurodesenvolvimento/genética , Deficiência Intelectual/genética , Fenótipo , Regulação da Expressão Gênica , Face , Proteínas Nucleares/genética , Histona Desmetilases/genética
6.
bioRxiv ; 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38168314

RESUMO

Metabolomic profiling is instrumental in understanding the systemic and cellular impact of inborn errors of metabolism (IEMs), monogenic disorders caused by pathogenic genomic variants in genes involved in metabolism. This study encompasses untargeted metabolomics analysis of plasma from 474 individuals and fibroblasts from 67 subjects, incorporating healthy controls, patients with 65 different monogenic diseases, and numerous undiagnosed cases. We introduce a web application designed for the in-depth exploration of this extensive metabolomics database. The application offers a user-friendly interface for data review, download, and detailed analysis of metabolic deviations linked to IEMs at the level of individual patients or groups of patients with the same diagnosis. It also provides interactive tools for investigating metabolic relationships and offers comparative analyses of plasma and fibroblast profiles. This tool emphasizes the metabolic interplay within and across biological matrices, enriching our understanding of metabolic regulation in health and disease. As a resource, the application provides broad utility in research, offering novel insights into metabolic pathways and their alterations in various disorders.

7.
BMJ Glob Health ; 7(Suppl 5)2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35798443

RESUMO

Non-communicable disease (NCD) prevention and care in humanitarian contexts has been a long-neglected issue. Healthcare systems in humanitarian settings have focused heavily on communicable diseases and immediate life-saving health needs. NCDs are a significant cause of morbidity and mortality in refugee settings, however, in many situations NCD care is not well integrated into primary healthcare services. Increased risk of poorer outcomes from COVID-19 for people living with NCDs has heightened the urgency of responding to NCDs and shone a spotlight on their relative neglect in these settings. Partnering with the United Nations Refugee Agency (UNHCR) since 2014, Primary Care International has provided clinical guidance and Training of Trainer (ToT) courses on NCDs to 649 health professionals working in primary care in refugee settings in 13 countries. Approximately 2300 healthcare workers (HCW) have been reached through cascade trainings over the last 6 years. Our experience has shown that, despite fragile health services, high staff turnover and competing clinical priorities, it is possible to improve NCD knowledge, skills and practice. ToT programmes are a feasible and practical format to deliver NCD training to mixed groups of HCW (doctors, nurses, technical officers, pharmacy technicians and community health workers). Clinical guidance must be adapted to local settings while co-creating an enabling environment for health workers is essential to deliver accessible, high-quality continuity of care for NCDs. On-going support for non-clinical systems change is equally critical for sustained impact. A shared responsibility for cascade training-and commitment from local health partners-is necessary to raise NCD awareness, influence local and national policy and to meet the UNHCR's objective of facilitating access to integrated prevention and control of NCDs.


Assuntos
COVID-19 , Doenças não Transmissíveis , Refugiados , Agentes Comunitários de Saúde , Mão de Obra em Saúde , Humanos , Doenças não Transmissíveis/prevenção & controle , Atenção Primária à Saúde , Nações Unidas
8.
Cell Signal ; 94: 110333, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35430346

RESUMO

G-protein coupled receptor (GPCR) kinases (GRKs) and ß-arrestins play key roles in GPCR and non-GPCR cellular responses. In fact, GRKs and arrestins are involved in a plethora of pathways vital for physiological maintenance of inter- and intracellular communication. Here we review decades of research literature spanning from the discovery, identification of key structural elements, and findings supporting the diverse roles of these proteins in GPCR-mediated pathways. We then describe how GRK2 and ß-arrestins partake in non-GPCR signaling and briefly summarize their involvement in various pathologies. We conclude by presenting gaps in knowledge and our prospective on the promising pharmacological potential in targeting these proteins and/or downstream signaling. Future research is warranted and paramount for untangling these novel and promising roles for GRK2 and arrestins in metabolism and disease progression.


Assuntos
Arrestinas , Quinases de Receptores Acoplados a Proteína G , Arrestinas/metabolismo , Quinases de Receptores Acoplados a Proteína G/metabolismo , Fosforilação , Receptores Acoplados a Proteínas G/metabolismo , Transdução de Sinais/fisiologia , beta-Arrestina 1/metabolismo , beta-Arrestina 2/metabolismo , beta-Arrestinas/metabolismo
9.
Nat Commun ; 13(1): 1532, 2022 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-35318315

RESUMO

Anxiety disorders are complex diseases, and often co-occur with depression. It is as yet unclear if a common neural circuit controls anxiety-related behaviors in both anxiety-alone and comorbid conditions. Here, utilizing the chronic social defeat stress (CSDS) paradigm that induces singular or combined anxiety- and depressive-like phenotypes in mice, we show that a ventral tegmental area (VTA) dopamine circuit projecting to the basolateral amygdala (BLA) selectively controls anxiety- but not depression-like behaviors. Using circuit-dissecting ex vivo electrophysiology and in vivo fiber photometry approaches, we establish that expression of anxiety-like, but not depressive-like, phenotypes are negatively correlated with VTA → BLA dopamine neuron activity. Further, our optogenetic studies demonstrate a causal link between such neuronal activity and anxiety-like behaviors. Overall, these data establish a functional role for VTA → BLA dopamine neurons in bi-directionally controlling anxiety-related behaviors not only in anxiety-alone, but also in anxiety-depressive comorbid conditions in mice.


Assuntos
Complexo Nuclear Basolateral da Amígdala , Animais , Ansiedade , Transtornos de Ansiedade , Neurônios Dopaminérgicos/metabolismo , Mesencéfalo , Camundongos , Estresse Psicológico , Área Tegmentar Ventral/fisiologia
10.
Neurology ; 98(20): e2046-e2059, 2022 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-35314505

RESUMO

BACKGROUND AND OBJECTIVES: KCNC2 encodes Kv3.2, a member of the Shaw-related (Kv3) voltage-gated potassium channel subfamily, which is important for sustained high-frequency firing and optimized energy efficiency of action potentials in the brain. The objective of this study was to analyze the clinical phenotype, genetic background, and biophysical function of disease-associated Kv3.2 variants. METHODS: Individuals with KCNC2 variants detected by exome sequencing were selected for clinical, further genetic, and functional analysis. Cases were referred through clinical and research collaborations. Selected de novo variants were examined electrophysiologically in Xenopus laevis oocytes. RESULTS: We identified novel KCNC2 variants in 18 patients with various forms of epilepsy, including genetic generalized epilepsy (GGE), developmental and epileptic encephalopathy (DEE) including early-onset absence epilepsy, focal epilepsy, and myoclonic-atonic epilepsy. Of the 18 variants, 10 were de novo and 8 were classified as modifying variants. Eight drug-responsive patients became seizure-free using valproic acid as monotherapy or in combination, including severe DEE cases. Functional analysis of 4 variants demonstrated gain of function in 3 severely affected DEE cases and loss of function in 1 case with a milder phenotype (GGE) as the underlying pathomechanisms. DISCUSSION: These findings implicate KCNC2 as a novel causative gene for epilepsy and emphasize the critical role of KV3.2 in the regulation of brain excitability.


Assuntos
Epilepsia Generalizada , Epilepsia , Epilepsia/genética , Epilepsia Generalizada/genética , Humanos , Fenótipo , Convulsões/genética , Canais de Potássio Shaw/genética , Sequenciamento do Exoma
11.
Diabetes Res Clin Pract ; : 108972, 2021 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-34343595

RESUMO

Executive Summary This document updates the 1999 World Health Organization (WHO) classification of diabetes. It prioritizes clinical care and guides health professionals in choosing appropriate treatments at the time of diabetes diagnosis, and provides practical guidance to clinicians in assigning a type of diabetes to individuals at the time of diagnosis. It is a compromise between clinical and aetiological classification because there remain gaps in knowledge of the aetiology and pathophysiology of diabetes. While acknowledging the progress that is being made towards a more precise categorization of diabetes subtypes, the aim of this document is to recommend a classification that is feasible to implement in different settings throughout the world. The revised classification is presented in Table 1. Unlike the previous classification, this classification does not recognize subtypes of type 1 diabetes and type 2 diabetes and includes new types of diabetes ("hybrid types of diabetes" and "unclassified diabetes").

12.
Genet Med ; 23(7): 1234-1245, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33824499

RESUMO

PURPOSE: Proline Rich 12 (PRR12) is a gene of unknown function with suspected DNA-binding activity, expressed in developing mice and human brains. Predicted loss-of-function variants in this gene are extremely rare, indicating high intolerance of haploinsufficiency. METHODS: Three individuals with intellectual disability and iris anomalies and truncating de novo PRR12 variants were described previously. We add 21 individuals with similar PRR12 variants identified via matchmaking platforms, bringing the total number to 24. RESULTS: We observed 12 frameshift, 6 nonsense, 1 splice-site, and 2 missense variants and one patient with a gross deletion involving PRR12. Three individuals had additional genetic findings, possibly confounding the phenotype. All patients had developmental impairment. Variable structural eye defects were observed in 12/24 individuals (50%) including anophthalmia, microphthalmia, colobomas, optic nerve and iris abnormalities. Additional common features included hypotonia (61%), heart defects (52%), growth failure (54%), and kidney anomalies (35%). PrediXcan analysis showed that phecodes most strongly associated with reduced predicted PRR12 expression were enriched for eye- (7/30) and kidney- (4/30) phenotypes, such as wet macular degeneration and chronic kidney disease. CONCLUSION: These findings support PRR12 haploinsufficiency as a cause for a novel disorder with a wide clinical spectrum marked chiefly by neurodevelopmental and eye abnormalities.


Assuntos
Haploinsuficiência , Deficiência Intelectual , Animais , Haploinsuficiência/genética , Humanos , Deficiência Intelectual/genética , Camundongos , Hipotonia Muscular , Mutação de Sentido Incorreto , Fenótipo
13.
J Hered ; 112(1): 58-66, 2021 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-33245337

RESUMO

A growing body of research suggests that many clonal populations maintain genetic diversity even without occasional sexual reproduction. The purpose of our study was to document variation in single-nucleotide polymorphism (SNP) diversity, DNA content, and pathogen susceptibility in clonal lineages of the New Zealand freshwater snail, Potamopyrgus antipodarum. We studied snails that were collected from multiple field sites around a single lake (Lake Alexandrina), as well as isofemale clonal lineages that had been isolated and maintained in the laboratory. We used the kompetitive allele specific PCR (KASP) method to genotype our samples at 46 nuclear SNP sites, and we used flow cytometry to estimate DNA content. We found high levels of SNP diversity, both in our field samples and in our clonal laboratory lines. We also found evidence of high variation in DNA content among clones, even among clones with identical genotypes across all SNP sites. Controlled pathogen exposures of the laboratory populations revealed variation in susceptibility among distinct clonal genotypes, which was independent of DNA content. Taken together, these results show high levels of diversity among asexual snails, especially for DNA content, and they suggest rapid genome evolution in asexuals.


Assuntos
Ploidias , Polimorfismo de Nucleotídeo Único , Reprodução Assexuada/genética , Caramujos/genética , Animais , Genética Populacional , Genótipo , Nova Zelândia
14.
Nat Chem ; 13(2): 140-148, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33380742

RESUMO

Finding faster and simpler ways to screen protein sequence space to enable the identification of new biocatalysts for asymmetric synthesis remains both a challenge and a rate-limiting step in enzyme discovery. Biocatalytic strategies for the synthesis of chiral amines are increasingly attractive and include enzymatic asymmetric reductive amination, which offers an efficient route to many of these high-value compounds. Here we report the discovery of over 300 new imine reductases and the production of a large (384 enzymes) and sequence-diverse panel of imine reductases available for screening. We also report the development of a facile high-throughput screen to interrogate their activity. Through this approach we identified imine reductase biocatalysts capable of accepting structurally demanding ketones and amines, which include the preparative synthesis of N-substituted ß-amino ester derivatives via a dynamic kinetic resolution process, with excellent yields and stereochemical purities.


Assuntos
Ensaios de Triagem em Larga Escala/métodos , Oxirredutases/isolamento & purificação , Aminação/efeitos dos fármacos , Aminas/química , Biocatálise , Iminas/metabolismo , Cetonas/química , Oxirredutases/metabolismo , Estereoisomerismo
15.
Biol Psychiatry ; 88(12): 910-921, 2020 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-32680583

RESUMO

BACKGROUND: Microglia, the primary immune cells of the brain, are implicated in alcohol use disorder. However, it is not known if microglial activation contributes to the transition from alcohol use to alcohol use disorder or is a consequence of alcohol intake. METHODS: We investigated the role of microglia in a mouse model of alcohol dependence using a colony stimulating factor 1 receptor inhibitor (PLX5622) to deplete microglia and a chronic intermittent ethanol vapor two-bottle choice drinking procedure. Additionally, we examined anxiety-like behavior during withdrawal. We then analyzed synaptic neuroadaptations in the central nucleus of the amygdala (CeA) and gene expression changes in the medial prefrontal cortex and CeA from the same animals used for behavioral studies. RESULTS: PLX5622 prevented escalations in voluntary alcohol intake and decreased anxiety-like behavior associated with alcohol dependence. PLX5622 also reversed expression changes in inflammatory-related genes and glutamatergic and GABAergic (gamma-aminobutyric acidergic) genes in the medial prefrontal cortex and CeA. At the cellular level in these animals, microglia depletion reduced inhibitory GABAA and excitatory glutamate receptor-mediated synaptic transmission in the CeA, supporting the hypothesis that microglia regulate dependence-induced changes in neuronal function. CONCLUSIONS: Our multifaceted approach is the first to link microglia to the molecular, cellular, and behavioral changes associated with the development of alcohol dependence, suggesting that microglia may also be critical for the development and progression of alcohol use disorder.


Assuntos
Alcoolismo , Consumo de Bebidas Alcoólicas , Alcoolismo/genética , Animais , Etanol , Genômica , Camundongos , Microglia , Transmissão Sináptica
16.
Neuropharmacology ; 175: 108176, 2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32497591

RESUMO

Alcohol use disorder (AUD) places a tremendous burden on society, with approximately two billion alcohol users in the world. While most people drink alcohol recreationally, a subpopulation (3-5%) engages in reckless and compulsive drinking, leading to the development of AUD and alcohol dependence. The Ventral Tegmental Area (VTA)-Nucleus Accumbens (NAc) circuit has been shown to encode rewarding stimuli and drive individual alcohol drinking behavior. Our previous work successfully separated C57BL/6J isogenic mice into high or low alcohol drinking subgroups after a 12-day, two-bottle choice voluntary alcohol access paradigm. Electrophysiological studies revealed that low alcohol drinking mice exhibited elevated spontaneous and burst firing properties of their VTA dopamine (DA) neurons and specifically mimicking this pattern of activity in VTA-NAc neurons in high alcohol drinking mice using optogenetics decreased their alcohol preference. It is also known that VTA DA neurons encode the salience and rewarding properties of external stimuli while also regulating downstream dopamine concentrations. Here, as a follow-up to this study, we utilized Fast Scan Cyclic Voltammetry (FSCV) to examine dopamine release in the NAc shell and core between alcohol drinking groups. We observed dynamic changes of dopamine release in the core of high drinking mice, but failed to see widely significant differences of dopamine release in the shell of both groups, when compared with ethanol-naive controls. Overall, the present data suggest subregion-specific differences of evoked dopamine release in the NAc of low and high alcohol drinking mice, and may provide an anatomical substrate for individual alcohol drinking behavior. This article is part of the special issue on Stress, Addiction and Plasticity.


Assuntos
Consumo de Bebidas Alcoólicas/metabolismo , Dopamina/metabolismo , Núcleo Accumbens/metabolismo , Animais , Etanol/administração & dosagem , Masculino , Camundongos Endogâmicos C57BL
17.
Sci Adv ; 6(21): eaay9320, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32494734

RESUMO

Imine reductases (IREDs) have shown great potential as catalysts for the asymmetric synthesis of industrially relevant chiral amines, but a limited understanding of sequence activity relationships makes rational engineering challenging. Here, we describe the characterization of 80 putative and 15 previously described IREDs across 10 different transformations and confirm that reductive amination catalysis is not limited to any particular subgroup or sequence motif. Furthermore, we have identified another dehydrogenase subgroup with chemoselectivity for imine reduction. Enantioselectivities were determined for the reduction of the model substrate 2-phenylpiperideine, and the effect of changing the reaction conditions was also studied for the reductive aminations of 1-indanone, acetophenone, and 4-methoxyphenylacetone. We have performed sequence-structure analysis to help explain clusters in activity across a phylogenetic tree and to inform rational engineering, which, in one case, has conferred a change in chemoselectivity that had not been previously observed.

18.
Neuropsychopharmacology ; 45(9): 1557-1566, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32428928

RESUMO

Lithium has been used to treat major depressive disorder, yet the neural circuit mechanisms underlying this therapeutic effect remain unknown. Here, we demonstrated that the ventral tegmental area (VTA) dopamine (DA) neurons that project to the medial prefrontal cortex (mPFC), but not to nucleus accumbens (NAc), contributed to the antidepressive-like effects of lithium. Projection-specific electrophysiological recordings revealed that high concentrations of lithium increased firing rates in mPFC-, but not NAc-, projecting VTA DA neurons in mice treated with chronic unpredictable mild stress (CMS). In parallel, chronic administration of high-dose lithium in CMS mice restored the firing properties of mPFC-projecting DA neurons, and also rescued CMS-induced depressive-like behaviors. Nevertheless, chronic lithium treatment was insufficient to change the basal firing rates in NAc-projecting VTA DA neurons. Furthermore, chemogenetic activation of mPFC-, but not NAc-, projecting VTA DA neurons mimicked the antidepressive-like effects of lithium in CMS mice. Chemogenetic downregulation of VTA-mPFC DA neurons' firing activity abolished the antidepressive-like effects of lithium in CMS mice. Finally, we found that the antidepressant-like effects induced by high-dose lithium were mediated by BNDF signaling in the mesocortical DA circuit. Together, these results demonstrated the role of mesocortical DA projection in antidepressive-like effects of lithium and established a circuit foundation for lithium-based antidepressive treatment.


Assuntos
Fator Neurotrófico Derivado do Encéfalo , Transtorno Depressivo Maior , Animais , Antidepressivos/farmacologia , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Lítio , Camundongos , Núcleo Accumbens/metabolismo , Córtex Pré-Frontal/metabolismo , Área Tegmentar Ventral/metabolismo
19.
Curr Biol ; 30(10): 1845-1854.e4, 2020 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-32302586

RESUMO

Fluid navigation requires constant updating of planned movements to adapt to evolving obstacles and goals. For that reason, a neural substrate for navigation demands spatial and environmental information and the ability to effect actions through efferents. The secondary motor cortex (M2) is a prime candidate for this role given its interconnectivity with association cortices that encode spatial relationships and its projection to the primary motor cortex. Here, we report that M2 neurons robustly encode both planned and current left/right turning actions across multiple turn locations in a multi-route navigational task. Comparisons within a common statistical framework reveal that M2 neurons differentiate contextual factors, including environmental position, route, action sequence, orientation, and choice availability. Despite significant modulation by environmental factors, action planning, and execution are the dominant output signals of M2 neurons. These results identify the M2 as a structure integrating spatial information toward the updating of planned movements.


Assuntos
Córtex Motor/fisiologia , Orientação Espacial/fisiologia , Navegação Espacial/fisiologia , Animais , Comportamento Animal/fisiologia , Masculino , Ratos , Ratos Sprague-Dawley
20.
J Am Chem Soc ; 141(49): 19208-19213, 2019 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-31743008

RESUMO

Ene-reductases (EREDs) catalyze the reduction of electron-deficient C═C bonds. Herein, we report the first example of ERED-catalyzed net reduction of C═C bonds of enimines (α,ß-unsaturated imines). Preliminary studies suggest their hydrolyzed ring-open ω-amino enones are the likely substrates for this step. When combined with imine reductase (IRED)-mediated C═N reduction, the result is an efficient telescoped sequence for the preparation of diastereomerically enriched 2-substituted saturated amine heterocycles.


Assuntos
Biocatálise , Compostos Heterocíclicos/síntese química , Iminas/química , Oxirredutases/química , Compostos Heterocíclicos/química , Estrutura Molecular , Oxirredução , Estereoisomerismo
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