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1.
Cereb Cortex ; 34(6)2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38836287

RESUMO

Somatic mutations have been identified in 10% to 63% of focal cortical dysplasia type II samples, primarily linked to the mTOR pathway. When the causative genetic mutations are not identified, this opens the possibility of discovering new pathogenic genes or pathways that could be contributing to the condition. In our previous study, we identified a novel candidate pathogenic somatic variant of IRS-1 c.1791dupG in the brain tissue of a child with focal cortical dysplasia type II. This study further explored the variant's role in causing type II focal cortical dysplasia through in vitro overexpression in 293T and SH-SY5Y cells and in vivo evaluation via in utero electroporation in fetal brains, assessing effects on neuronal migration, morphology, and network integrity. It was found that the mutant IRS-1 variant led to hyperactivity of p-ERK, increased cell volume, and was predominantly associated with the MAPK signaling pathway. In vivo, the IRS-1 c.1791dupG variant induced abnormal neuron migration, cytomegaly, and network hyperexcitability. Notably, the ERK inhibitor GDC-0994, rather than the mTOR inhibitor rapamycin, effectively rescued the neuronal defects. This study directly highlighted the ERK signaling pathway's role in the pathogenesis of focal cortical dysplasia II and provided a new therapeutic target for cases of focal cortical dysplasia II that are not treatable by rapamycin analogs.


Assuntos
Proteínas Substratos do Receptor de Insulina , Sistema de Sinalização das MAP Quinases , Mutação , Humanos , Proteínas Substratos do Receptor de Insulina/genética , Proteínas Substratos do Receptor de Insulina/metabolismo , Sistema de Sinalização das MAP Quinases/genética , Animais , Malformações do Desenvolvimento Cortical do Grupo I/genética , Malformações do Desenvolvimento Cortical do Grupo I/metabolismo , Encéfalo/metabolismo , Encéfalo/patologia , Neurônios/metabolismo , Neurônios/patologia , Movimento Celular/genética , Células HEK293 , Feminino , Displasia Cortical Focal , Epilepsia
2.
J Neurosci ; 43(21): 3949-3969, 2023 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-37037606

RESUMO

Autism spectrum disorder (ASD) is a neurodevelopmental disorder with highly heritable heterogeneity. Mutations of CUB and sushi multiple domains 3 (CSMD3) gene have been reported in individuals with ASD. However, the underlying mechanisms of CSMD3 for the onset of ASD remain unexplored. Here, using male CSMD3 knock-out (CSMD3 -/-) mice, we found that genetic deletion of CSMD3 produced core autistic-like symptoms (social interaction deficits, restricted interests, and repetitive and stereotyped behaviors) and motor dysfunction in mice, indicating that the CSMD3 gene can be considered as a candidate for ASD. Moreover, we discovered that the ablation of CSMD3 in mice led to abnormal cerebellar Purkinje cell (PC) morphology in Crus I/II lobules, including aberrant developmental dendritogenesis and spinogenesis of PCs. Furthermore, combining in vivo fiber photometry calcium imaging and ex vivo electrophysiological recordings, we showed that the CSMD3 -/- mice exhibited an increased neuronal activity (calcium fluorescence signals) in PCs of Crus I/II lobules in response to movement activity, as well as an enhanced intrinsic excitability of PCs and an increase of excitatory rather than inhibitory synaptic input to the PCs, and an impaired long-term depression at the parallel fiber-PC synapse. These results suggest that CSMD3 plays an important role in the development of cerebellar PCs. Loss of CSMD3 causes abnormal PC morphology and dysfunction in the cerebellum, which may underlie the pathogenesis of motor deficits and core autistic-like symptoms in CSMD3 -/- mice. Our findings provide novel insight into the pathophysiological mechanisms by which CSMD3 mutations cause impairments in cerebellar function that may contribute to ASD.SIGNIFICANCE STATEMENT Autism spectrum disorder (ASD) is a neurodevelopmental disorder with highly heritable heterogeneity. Advances in genomic analysis have contributed to numerous candidate genes for the risk of ASD. Recently, a novel giant gene CSMD3 encoding a protein with CUB and sushi multiple domains (CSMDs) has been identified as a candidate gene for ASD. However, the underlying mechanisms of CSMD3 for the onset of ASD remain largely unknown. Here, we unravel that loss of CSMD3 results in abnormal morphology, increased intrinsic excitabilities, and impaired synaptic plasticity in cerebellar PCs, subsequently leading to motor deficits and ASD-like behaviors in mice. These results provide novel insight into the pathophysiological mechanisms by which CSMD3 mutations cause impairments in cerebellar function that may contribute to ASD.


Assuntos
Transtorno do Espectro Autista , Transtorno Autístico , Transtornos Motores , Animais , Masculino , Camundongos , Cálcio/metabolismo , Cerebelo/fisiologia , Camundongos Knockout , Transtornos Motores/genética , Transtornos Motores/metabolismo , Células de Purkinje/fisiologia
3.
Ann Neurol ; 94(6): 1136-1154, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37597256

RESUMO

OBJECTIVE: Rare variants of CCNK (cyclin K) give rise to a syndrome with intellectual disability. The purpose of this study was to describe the genotype-phenotype spectrum of CCNK-related syndrome and the underlying molecular mechanisms of pathogenesis. METHODS: We identified a number of de novo CCNK variants in unrelated patients. We generated patient-induced pluripotent stem cells (iPSCs) and neural progenitor cells (NPCs) as disease models. In addition, we constructed NPC-specific Ccnk knockout (KO) mice and performed molecular and morphological analyses. RESULTS: We identified 2 new patients harboring CCNK missense variants and followed-up 3 previous reported patients, which constitute the largest patient population analysis of the disease. We demonstrate that both the patient-derived NPC models and the Ccnk KO mouse displayed deficient NPC proliferation and enhanced apoptotic cell death. RNA sequencing analyses of these NPC models uncovered transcriptomic signatures unique to CCNK-related syndrome, revealing significant changes in genes, including WNT5A, critical for progenitor proliferation and cell death. Further, to confirm WNT5A's role, we conducted rescue experiments using NPC and mouse models. We found that a Wnt5a inhibitor significantly increased proliferation and reduced apoptosis in NPCs derived from patients with CCNK-related syndrome and NPCs in the developing cortex of Ccnk KO mice. INTERPRETATION: We discussed the genotype-phenotype relationship of CCNK-related syndrome. Importantly, we demonstrated that CCNK plays critical roles in NPC proliferation and NPC apoptosis in vivo and in vitro. Together, our study highlights that Wnt5a may serve as a promising therapeutic target for the disease intervention. ANN NEUROL 2023;94:1136-1154.


Assuntos
Deficiência Intelectual , Células-Tronco Neurais , Camundongos , Animais , Humanos , Células-Tronco Neurais/metabolismo , Transdução de Sinais/genética , Ciclinas/metabolismo , Apoptose
4.
Crit Rev Biotechnol ; : 1-20, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38566472

RESUMO

ß-Hydroxy-α-amino acids (ß-HAAs) have extensive applications in the pharmaceutical, chemical synthesis, and food industries. The development of synthetic methodologies aimed at producing optically pure ß-HAAs has been driven by practical applications. Among the various synthetic methods, biocatalytic asymmetric synthesis is considered a sustainable approach due to its capacity to generate two stereogenic centers from simple prochiral precursors in a single step. Therefore, extensive efforts have been made in recent years to search for effective enzymes which enable such biotransformation. This review provides an overview on the discovery and engineering of C-C bond formation enzymes for the biocatalytic synthesis of ß-HAAs. We highlight examples where the use of threonine aldolases, threonine transaldolases, serine hydroxymethyltransferases, α-methylserine aldolases, α-methylserine hydroxymethyltransferases, and engineered alanine racemases facilitated the synthesis of ß-HAAs. Additionally, we discuss the potential future advancements and persistent obstacles in the enzymatic synthesis of ß-HAAs.

5.
Prenat Diagn ; 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38898598

RESUMO

BACKGROUND: The advent of next-generation sequencing (NGS) has enhanced the diagnostic efficacy for monogenic diseases, while presenting challenges in achieving consistent diagnoses. METHOD: We retrospectively analyzed the concordance rate and reasons for the inconsistency between the original diagnostic result from the genetic testing laboratory and the variant validation result from the prenatal diagnostic center. The validation procedure comprised three stages: validation of variant detection, reevaluation of variant classification, and assessment of recurrence risk, which involved verifying the mode of inheritance and parental carriage. RESULT: In total, 17 (6%) of the 286 families affected by rare monogenic diseases showed different results during the variant validation procedure. These cases comprised four (23.5%) with variant detection errors, 12 (70.5%) with inconsistent interpretation, and one (6%) with non-Mendelian inheritance patterns. False-positive NGS results confirmed by Sanger sequencing were related to pseudogenes and GC-rich regions. The classification of the 17 variants was altered in the 12 cases owing to various factors. The case with an atypical inheritance pattern was originally considered autosomal recessive inheritance, but was diagnosed as maternal uniparental disomy after additional genetic analysis. CONCLUSION: We underscored the significance of variant validation by prenatal diagnostic centers. Families affected by monogenic diseases with reproductive plans should be referred to prenatal genetic centers as early as possible to avoid different results that may postpone subsequent prenatal diagnosis.

6.
Epilepsia ; 64(11): 2968-2981, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37577761

RESUMO

OBJECTIVE: To investigate the clinical features and potential pathogenesis mechanism of de novo CLPTM1 variants associated with epilepsy. METHODS: Identify de novo genetic variants associated with epilepsy by reanalyzing trio-based whole-exome sequencing data. We analyzed the clinical characteristics of patients with these variants and performed functional in vitro studies in cells expressing mutant complementary DNA for these variants using whole-cell voltage-clamp current recordings and outside-out patch-clamp recordings from transiently transfected human embryonic kidney (HEK) cells. RESULTS: Two de novo missense variants related to epilepsy were identified in the CLPTM1 gene. Functional studies indicated that CLPTM1-p.R454H and CLPTM1-p.R568Q variants reduced the γ-aminobutyric acid A receptor (GABAA R) current response amplitude recorded under voltage clamp compared to the wild-type receptors. These variants also reduced the charge transfer and altered the time course of desensitization and deactivation following rapid removal of GABA. The surface expression of the GABAA R γ2 subunit from the CLPTM1-p.R568Q group was significantly reduced compared to CLPTM1-WT. SIGNIFICANCE: This is the first report of functionally relevant variants within the CLPTM1 gene. Patch-clamp recordings showed that these de novo CLPTM1 variants reduce GABAA R currents and charge transfer, which should promote excitation and hypersynchronous activity. This study may provide insights into the molecular mechanisms of the CLPTM1 variants underlying the patients' phenotypes, as well as for exploring potential therapeutic targets for epilepsy.


Assuntos
Epilepsia , Receptores de GABA-A , Humanos , Receptores de GABA-A/genética , Receptores de GABA-A/metabolismo , Epilepsia/genética , Mutação de Sentido Incorreto/genética , Fenótipo , Ácido gama-Aminobutírico , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo
7.
Neurochem Res ; 48(1): 72-81, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35987975

RESUMO

Acitretin is an oral drug approved by the Food and Drug Administration that is commonly used to treat psoriasis. In recent years, acitretin has been identified as a candidate drug for the treatment of Alzheimer's disease, but its role in neuronal development is still unclear. In this study, the human neuroblastoma cell line SH-SY5Y was used as a model to study neuronal differentiation. We found that acitretin effectively promoted the differentiation of SH-SY5Y cells into neuronal cells and upregulated the expression of the neuronal marker ß-III tubulin and the mature neuronal marker NFH. Differentially expressed genes were identified by RNA sequencing and analyzed by bioinformatics approaches. The results showed that genes associated with neuron development-related pathways, such as SSPO and KCNT1, had significant changes in expression. Analysis showed that PRKCA and CAMK2B may play important roles in the process by which acitretin promotes neurodevelopment. Through whole-cell patch clamping and a microelectrode array assay, we found that acitretin-treated neurons generated electrical spikes similar to those generated by mature neurons. This study provided evidence to support an accessible and safe model of neuron-like cells and verified that acitretin can promote the differentiation of neurons and has the potential to treat brain tumors and neurodevelopmental and neurodegenerative diseases.


Assuntos
Acitretina , Neuroblastoma , Humanos , Acitretina/farmacologia , Acitretina/metabolismo , Linhagem Celular Tumoral , Neuroblastoma/metabolismo , Neurônios/metabolismo , Diferenciação Celular/fisiologia , Canais de Potássio Ativados por Sódio/metabolismo , Proteínas do Tecido Nervoso/metabolismo
8.
Org Biomol Chem ; 21(8): 1737-1743, 2023 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-36723156

RESUMO

Three novel actinomycins, actimomycin S (1), neo-actinomycins C and D (2 and 3), and one new benzo[d]oxazole alkaloid (4) were isolated from the Streptomyces sp. strain S22, along with three known congeners F9 (5), X2 (6) and X0ß (7) and 2-acetylamino-3-hydroxyl-4-methyl-benzoic acid methyl ester (8). The structures of the new products were elucidated by spectroscopic methods, and the absolute configuration of amino acid residues was determined by Marfey's analysis. Actinomycin S contains an aspartic acid (Asp) residue in the ß-peptidolactone ring. This is the first report of an Asp residue within an actinomycin-type natural product. Notably, neo-actinomycins C and D feature a rare tetracyclic 5H-oxazolo[4,5-b]phenoxazine chromophore. Among these, neo-actinomycin D, with an unprecedented molecular formula, represents the highest molecular weight member in the actinomycin family. Actinomycins 1-3 exhibited antimicrobial activity against multiple resistant "ESKAPE" pathogens with MIC values ranging from 1.25 to 80.0 µg mL-1. In addition, 1-3 showed potent cytotoxic activities against the HepG2 liver carcinoma cell line with IC50 values of 0.10, 0.32, and 0.024 µM, respectively. Furthermore, 1 inhibited cell proliferation by inducing G0-G1 phase arrest in the cell cycle.


Assuntos
Antineoplásicos , Streptomyces , Dactinomicina , Streptomyces/metabolismo , Antineoplásicos/farmacologia , Análise Espectral , Aminoácidos/metabolismo
9.
Angew Chem Int Ed Engl ; 62(15): e202300772, 2023 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-36781392

RESUMO

It is very challenging to obtain stable room-temperature luminescent open-shell singlet diradicals. Herein we report the first stable Müller's hydrocarbon TTM-PhTTM with luminescent properties. Variable-temperature electron paramagnetic resonance spectroscopy measurements and theoretical calculations show that TTM-PhTTM has an open-shell singlet ground state with a diradical character of 90 %. Because of a small singlet-triplet energy gap, the open-shell singlet ground state can be thermally excited to a triplet state. TTM-PhTTM shows room-temperature deep-red emission in various solutions. Unusually high stability of TTM-PhTTM was also observed owing to effective steric hindrance and spin delocalization. Our results are beneficial to the rational design and discovery of more stable luminescent diradical materials.

10.
Hum Mutat ; 43(5): 568-581, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35143101

RESUMO

Genome sequencing (GS) has been used in the diagnosis of global developmental delay (GDD)/intellectual disability (ID). However, the performance of GS in patients with inconclusive results from chromosomal microarray analysis (CMA) and exome sequencing (ES) is unknown. We recruited 100 pediatric GDD/ID patients from multiple sites in China from February 2018 to August 2020 for GS. Patients have received at least one genomic diagnostic test before enrollment. Reanalysis of their CMA/ES data was performed. The yield of GS was calculated and explanations for missed diagnoses by CMA/ES were investigated. Clinical utility was assessed by interviewing the parents by phone. The overall diagnostic yield of GS was 21%. Seven cases could have been solved with reanalysis of ES data. Thirteen families were missed by previous CMA/ES due to improper methodology. Two remained unsolved after ES reanalysis due to complex variants missed by ES, and a CNV in untranslated regions. Follow-up of the diagnosed families revealed that nine families experienced changes in clinical management, including identification of targeted treatments, cessation of unnecessary treatment, and considerations for family planning. GS demonstrated high diagnostic yield and clinical utility in this undiagnosed GDD/ID cohort, detecting a wide range of variant types of different sizes in a single workflow.


Assuntos
Deficiência Intelectual , Criança , Deficiências do Desenvolvimento/diagnóstico , Deficiências do Desenvolvimento/genética , Humanos , Deficiência Intelectual/diagnóstico , Deficiência Intelectual/genética , Análise em Microsséries/métodos , Estudos Prospectivos , Sequenciamento do Exoma
11.
Am J Hum Genet ; 105(5): 996-1004, 2019 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-31587869

RESUMO

Mechanically activated (MA) ion channels convert physical forces into electrical signals. Despite the importance of this function, the involvement of mechanosensitive ion channels in human disease is poorly understood. Here we report heterozygous missense mutations in the gene encoding the MA ion channel TMEM63A that result in an infantile disorder resembling a hypomyelinating leukodystrophy. Four unrelated individuals presented with congenital nystagmus, motor delay, and deficient myelination on serial scans in infancy, prompting the diagnosis of Pelizaeus-Merzbacher (like) disease. Genomic sequencing revealed that all four individuals carry heterozygous missense variants in the pore-forming domain of TMEM63A. These variants were confirmed to have arisen de novo in three of the four individuals. While the physiological role of TMEM63A is incompletely understood, it is highly expressed in oligodendrocytes and it has recently been shown to be a MA ion channel. Using patch clamp electrophysiology, we demonstrated that each of the modeled variants result in strongly attenuated stretch-activated currents when expressed in naive cells. Unexpectedly, the clinical evolution of all four individuals has been surprisingly favorable, with substantial improvements in neurological signs and developmental progression. In the three individuals with follow-up scans after 4 years of age, the myelin deficit had almost completely resolved. Our results suggest a previously unappreciated role for mechanosensitive ion channels in myelin development.


Assuntos
Canais Iônicos/genética , Proteínas de Membrana/genética , Bainha de Mielina/genética , Doença de Pelizaeus-Merzbacher/genética , Adolescente , Adulto , Pré-Escolar , Feminino , Heterozigoto , Humanos , Masculino , Mutação de Sentido Incorreto/genética , Oligodendroglia/metabolismo , Adulto Jovem
12.
Anal Chem ; 94(42): 14769-14777, 2022 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-36219068

RESUMO

Herein, we have synthesized a series of three-photon fluorescent Pt(II) complexes targeting a tumor-associated biothiol, cysteine (Cys), which allows it to be detected without any interference from other intracellular proteins. We focused on how to significantly improve the fluorescence response of Cys via regulating the recognition units in probes. The reaction of K2PtCl4 with L-CH3 or L-COOEt in DMSO solution gave Lyso-Pt-CH3 and Lyso-Pt-COOEt, respectively, which present four-coordinated square-planar geometries in mononuclear structures. Lyso-Pt-CH3 consists of a Cys aptamer labeled with typical aggregation-induced emission (AIE) characteristics, which shows strong three-photon absorption cross section (3PA) only in the presence of Cys. It was found that Lyso-Pt-CH3 displayed a perfect signal-to-noise ratio for imaging lysosomes and for rapid detection of Cys. Using Lyso-Pt-CH3, Cys-related cellular mechanisms were proposed. We confirm that cystine (Cyss) could be absorbed in cells through cystine/glutamate antiporters (system xc-) and is then converted to Cys under the effect of enzymes. All of these suggest that Lyso-Pt-CH3 might be a potential candidate as a simple and straightforward biomarker of lysosome-related Cys in vitro. Lyso-Pt-CH3 can effectively identify tumor tissues with excessive levels of Cys. Lyso-Pt-CH3 also showed excellent antitumor activity than cisplatin. This work provides a novel strategy for the rational design of controllably activated and Cys-targeted Pt(II) anticancer prodrugs for clinical diagnosis and treatment.


Assuntos
Neoplasias , Pró-Fármacos , Humanos , Cisteína/metabolismo , Cistina/metabolismo , Cisplatino/metabolismo , Medicina de Precisão , Pró-Fármacos/farmacologia , Pró-Fármacos/uso terapêutico , Dimetil Sulfóxido , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Glutamatos , Antiporters , Corantes Fluorescentes/química
13.
Neurochem Res ; 47(12): 3747-3760, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36198922

RESUMO

Leukoencephalopathy with vanishing white matter (VWM) is an inherited leukoencephalopathy characterized by progressive rarefaction of cerebral white matter. Dysfunction of patient astrocyte plays a central role in the pathogenesis, while the immaturity of oligodendrocyte is probably secondary. How eIF2B mutant astrocytes affect the maturation and myelination of oligodendrocyte precursor cells (OPCs) is unclear yet. We used induced pluripotent stem cells (iPSCs) derived from our patient with EIF2B5 mutations to differentiate into astrocytes (AS) and OPCs, and aimed to verify that patient astrocytes inhibited the differentiation of OPCs by abnormalities of secreted proteins. eIF2B mutant astrocytes and astrocyte-conditioned medium (ACM) both inhibited the maturation of OPCs. It was revealed that 13 promising proteins exhibited a similar up- or downregulation by the PRM method correlated well with TMT results. eIF2B mutant astrocytes may secrete abnormal extracellular matrix (HA, LAMA4, BGN, FBN1, VASN, PCOLCE, MFAP4), cytokines (IL-6, CRABP1, ISG15), growth factors (PDGF-AA, CNTF, IGF-II, sFRP1, SERPINF1) and increased FABP7, which might lead to the differentiation and maturation disorder of OPCs. We analyzed the astrocyte-conditioned medium to find the key secretory molecules affecting the differentiation and maturation of OPCs, which provides potential clues for further research on the mechanism of VWM.


Assuntos
Células-Tronco Pluripotentes Induzidas , Leucoencefalopatias , Substância Branca , Humanos , Astrócitos/metabolismo , Meios de Cultivo Condicionados/farmacologia , Fator de Iniciação 2B em Eucariotos/genética , Células-Tronco Pluripotentes Induzidas/patologia , Leucoencefalopatias/genética , Leucoencefalopatias/patologia , Substância Branca/metabolismo
14.
Neurochem Res ; 47(12): 3723-3732, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36066699

RESUMO

Neuroblastoma is a type of developmental childhood cancer that arises from the neural crest. It is the most common pediatric solid tumor in the world. AM580 is a powerful cyto-differentiating molecule on acute promyelocytic leukemia cells and induced pluripotent stem cells, but its effect on neuroblastoma is still unknown. In this study, the neuronal differentiation impact of AM580 was investigated using the human neuroblastoma cell line SH-SY5Y as a model. AM580 successfully stimulated the SH-SY5Y cells to develop into neuron-like cells. Functional enrichment analysis of RNAseq data revealed that differentially expressed genes (DEGs) were substantially enriched for GO keywords and KEGG pathways linked to neuron development. Some potassium ion channel genes associated with neuronal excitation, such as KCNT1, were shown to be upregulated. Through the MEA tests, we found the AM580-induced neurons possessed electrical spikes as mature neurons. AM580 also induced the neuronal marker ß-tubulin III and mature neurons marker Neurofilament H. Our study proved that AM580 can promote the differentiation of neurons and has the potential to treat neuroblastoma, neurodevelopmental and neurodegenerative diseases.


Assuntos
Neuroblastoma , Humanos , Diferenciação Celular/fisiologia , Linhagem Celular Tumoral , Proteínas do Tecido Nervoso/metabolismo , Neuroblastoma/metabolismo , Neurônios/metabolismo , Canais de Potássio Ativados por Sódio
15.
Arch Microbiol ; 204(8): 500, 2022 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-35851419

RESUMO

Arthrobotrys oligospora is a model nematode-trapping fungus that has been extensively investigated to understand the interactions between fungi and nematodes. Nematode capture by A. oligospora is a complex process in which recognition of nematodes is generally believed to be mediated by lectins from the fungi. Lectins are a group of carbohydrate-binding proteins that widely exist in microorganisms and contain specific glycosylation recognition domains. In this work, we report the effect of a putative WSC domain-containing protein encoding gene AOL_s00043g401 (g401) on the growth and nematode-trapping of A. oligospora. The g401 gene was knocked out using the homologous recombination approach, and the △g401 mutant strain was then evaluated for its growth rate, conidial yield and germination rate, adaptation to environmental stresses, and nematocidal activity. Interestingly, the deletion of the putative lectin gene g401 had no significant effect on saprophytic growth, conidial yield and germination rate, responses to high salt, surfactant, and strong oxidative environments, as well as nematode-trapping efficiency of A. oligospora. We speculate that this phenomenon might have been caused by an intrinsic genetic compensation of the g401 in this fungus. For instance, more copies of WSC domain encoding genes or PQQ-DH domain encoding genes were found in the genome of A. oligospora. These findings provide further experimental evidence on the effect of lectin-related functional proteins in A. oligospora on nematode capture and will help further analyze their potential roles in the biological control of nematodes in the future.


Assuntos
Ascomicetos , Nematoides , Animais , Ascomicetos/fisiologia , Lectinas , Nematoides/genética , Esporos Fúngicos/genética
16.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 39(7): 680-684, 2022 Jul 10.
Artigo em Zh | MEDLINE | ID: mdl-35810420

RESUMO

OBJECTIVE: To explore the clinical and genetic characteristics of three children with 22q13 deletion syndrome. METHODS: Clinical data were collected and copy number variations in the patients and their parents were detected by using array-based comparative genomic hybridization (aCGH) and copy number variation sequencing (CNV-seq). The DECIPHER, ClinGen, OMIM, PubMed and Gene Review databases were retrieved for pathogenicity analysis. RESULTS: The common phenotypes of the three children have included variable global developmental delay, among which speech delay was the most obvious. Patient 1 had abnormalities of corpus callosum shown by magnetic resonance imaging. Patient 2 had dental crowding, pale skin, thick palms, hypotonia, and other facial features. Patient 3 had the mildest symptoms including language dysfunction, which has caught up with the development and improved significantly. All of the three children had harbored de novo deletions of 22q13.33q13.33 region, which spanned 0.84 Mb, 8.70 Mb and 0.90 Mb and involved 37, 126, and 34 genes, respectively. CONCLUSION: Above finding has enriched the clinical and genetic characteristics of 22q13 deletion syndrome and laid a foundation for genetic counseling and prenatal diagnosis.


Assuntos
Transtornos Cromossômicos , Variações do Número de Cópias de DNA , Deleção Cromossômica , Transtornos Cromossômicos/genética , Cromossomos Humanos Par 22/genética , Hibridização Genômica Comparativa/métodos , Humanos
17.
Am J Hum Genet ; 103(3): 448-455, 2018 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-30122539

RESUMO

Neurodevelopment is a transcriptionally orchestrated process. Cyclin K, a regulator of transcription encoded by CCNK, is thought to play a critical role in the RNA polymerase II-mediated activities. However, dysfunction of CCNK has not been linked to genetic disorders. In this study, we identified three unrelated individuals harboring de novo heterozygous copy number loss of CCNK in an overlapping 14q32.3 region and one individual harboring a de novo nonsynonymous variant c.331A>G (p.Lys111Glu) in CCNK. These four individuals, though from different ethnic backgrounds, shared a common phenotype of developmental delay and intellectual disability (DD/ID), language defects, and distinctive facial dysmorphism including high hairline, hypertelorism, thin eyebrows, dysmorphic ears, broad nasal bridge and tip, and narrow jaw. Functional assay in zebrafish larvae showed that Ccnk knockdown resulted in defective brain development, small eyes, and curly spinal cord. These defects were partially rescued by wild-type mRNA coding CCNK but not the mRNA with the identified likely pathogenic variant c.331A>G, supporting a causal role of CCNK variants in neurodevelopmental disorders. Taken together, we reported a syndromic neurodevelopmental disorder with DD/ID and facial characteristics caused by CCNK variations, possibly through a mechanism of haploinsufficiency.


Assuntos
Anormalidades Múltiplas/genética , Anormalidades Craniofaciais/genética , Ciclinas/genética , Deficiências do Desenvolvimento/genética , Atrofia Muscular/genética , Mutação/genética , Transtornos do Neurodesenvolvimento/genética , Adolescente , Animais , Criança , Pré-Escolar , Feminino , Haploinsuficiência/genética , Heterozigoto , Humanos , Hipertelorismo/genética , Deficiência Intelectual/genética , Masculino , Anormalidades Musculoesqueléticas/genética , Malformações do Sistema Nervoso/genética , Fenótipo , Síndrome , Peixe-Zebra
18.
J Hum Genet ; 66(8): 761-768, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33597727

RESUMO

Hypomyelinating leukodystrophies (HLDs) are a rare group of disorders characterized by myelin deficit of the brain-based on MRI. Here, we studied 20 patients with unexplained HLD to uncover their genetic etiology through whole-exome sequencing (WES). Trio-based WES was performed for 20 unresolved HLDs families after genetic tests for the PLP1 duplication and a panel of 115 known leukodystrophy-related genes. Variants in both known genes that related to HLDs and promising candidate genes were analyzed. Minigene splicing assay was conducted to confirm the effect of splice region variant. All 20 patients were diagnosed with HLDs clinically based on myelin deficit on MRI and impaired motor ability. Through WES, in 11 of 20 trios, 15 causative variants were detected in seven genes TUBB4A, POLR1C, POLR3A, SOX10, TMEM106B, DEGS1, and TMEM63A. The last three genes have just been discovered. Of 15 variants, six were novel. Using minigene splicing assay, splice variant POLR3A c.1770 + 5 G > C was proved to disrupt the normal splicing of intron 13 and led to a premature stop codon at position 618 (p.(P591Vfs*28)). Our analysis determined the molecular diagnosis of 11 HLDs patients. It emphasizes the heterogenicity of HLDs, the diagnostic power of trio-based WES for HLDs. Comprehensive analysis including a focus on candidate genes helps to discover novel disease-causing genes, determine the diagnosis for the first time, and improve the yield of WES. Moreover, novel mutations identified in TUBB4A, POLR3A, and POLR1C expand the mutation spectrum of these genes.


Assuntos
Predisposição Genética para Doença , Variação Genética , Doenças Desmielinizantes Hereditárias do Sistema Nervoso Central/genética , Canais de Cálcio/genética , Criança , Pré-Escolar , RNA Polimerases Dirigidas por DNA/genética , Ácidos Graxos Dessaturases/genética , Feminino , Testes Genéticos , Doenças Desmielinizantes Hereditárias do Sistema Nervoso Central/diagnóstico , Humanos , Lactente , Imageamento por Ressonância Magnética , Masculino , Proteínas de Membrana/genética , Mutação , Bainha de Mielina/metabolismo , Proteínas do Tecido Nervoso/genética , RNA Polimerase III/genética , Splicing de RNA , Fatores de Transcrição SOXE/genética , Tubulina (Proteína)/genética , Sequenciamento do Exoma
19.
J Nutr ; 151(8): 2296-2304, 2021 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-33979838

RESUMO

BACKGROUND: Overweight or obesity among pregnant women may compromise maternal and neonatal iron status by upregulating hepcidin. OBJECTIVES: This study determined the association of 1) maternal and neonatal iron status with maternal and neonatal hepcidin concentrations, and 2) maternal prepregnancy weight status with maternal and neonatal hepcidin concentrations. METHODS: We examined hematologic data from 405 pregnant women and their infants from the placebo treatment group of a pregnancy iron supplementation trial in rural China. We measured hepcidin, serum ferritin (SF), soluble transferrin receptor (sTfR), and high-sensitivity C-reactive protein in maternal blood samples at mid-pregnancy and in cord blood at delivery. We used regression analysis to examine the association of maternal prepregnancy overweight or obese status with maternal hepcidin concentration in mid-pregnancy and cord hepcidin concentrations. We also used path analysis to examine mediation of the association of maternal prepregnancy overweight or obese status with maternal iron status by maternal hepcidin, as well as with neonatal hepcidin by neonatal iron status. RESULTS: Maternal iron status was positively correlated with maternal hepcidin at mid-pregnancy (SF: r = 0.63, P < 0.001; sTfR: r = -0.37, P < 0.001). Neonatal iron status was also positively correlated with cord hepcidin (SF: r = 0.61, P < 0.001; sTfR: r = -0.39, P < 0.001). In multiple linear regression models, maternal prepregnancy overweight or obese status was not associated with maternal hepcidin at mid-pregnancy but was associated with lower cord hepcidin (coefficient = -0.21, P = 0.004). Using path analysis, we observed a significant indirect effect of maternal prepregnancy overweight or obese status on cord hepcidin, mediated by neonatal iron status. CONCLUSIONS: In both pregnant women and neonates, hepcidin was responsive to iron status. Maternal prepregnancy overweight status, with or without including obese women, was associated with lower cord blood hepcidin, likely driven by lower iron status among the neonates of these mothers.


Assuntos
Hepcidinas , Sobrepeso , Feminino , Ferritinas , Hepcidinas/metabolismo , Humanos , Recém-Nascido , Obesidade/complicações , Gravidez , Receptores da Transferrina
20.
Arch Gynecol Obstet ; 304(5): 1153-1160, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34390384

RESUMO

BACKGROUND: Autoimmune diseases as antiphospholipid syndrome (APS) and systemic lupus erythematosus (SLE) could cause many maternal complications. The most common maternal complications of autoimmune diseases are lupus flare, hypertension, nephritis, preeclampsia (PE), eclampsia, and poor pregnancy outcomes which including preterm delivery and pregnancy loss. Only the lupus anticoagulant in the greatest prospective multicenter study has been associated with adverse pregnancy outcomes of the APS. PURPOSE: This review aims to provide a comprehensive update for predictors in pregnant women with APS/SLE. METHODS: These data have been collected from clinical and pathological studies, systematic reviews, and meta-analysis. RESULTS: In recent years the SLE and APS demonstrated to have different and valuable clinical and biomarker predictors for the pregnancy outcome. Treatment of pregnant women with APS is low molecular weight heparin (LMWH) and aspirin; however, around 75% of this management is considered successful. CONCLUSION: This review summarizes recent research that focuses on biochemical and clinical predictors of adverse pregnancy outcomes (APOs) of pregnant women with SLE and APS. Furthermore, we have collected more evidence that confirms the safety and efficacy of hydroxychloroquine (HCQ) preventing APOs.


Assuntos
Síndrome Antifosfolipídica/tratamento farmacológico , Aspirina/uso terapêutico , Heparina de Baixo Peso Molecular/uso terapêutico , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Complicações na Gravidez/tratamento farmacológico , Adulto , Síndrome Antifosfolipídica/complicações , Síndrome Antifosfolipídica/diagnóstico , Feminino , Humanos , Recém-Nascido , Lúpus Eritematoso Sistêmico/complicações , Gravidez , Complicações na Gravidez/imunologia , Resultado da Gravidez , Gestantes , Exacerbação dos Sintomas
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