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1.
Mol Psychiatry ; 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38503925

RESUMO

Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by impaired social interactions, communication deficits and repetitive behaviors. A study of autistic human subjects has identified RFWD2 as a susceptibility gene for autism, and autistic patients have 3 copies of the RFWD2 gene. The role of RFWD2 as an E3 ligase in neuronal functions, and its contribution to the pathophysiology of ASD, remain unknown. We generated RFWD2 knockin mice to model the human autistic condition of high gene dosage of RFWD2. We found that heterozygous knockin (Rfwd2+/-) male mice exhibited the core symptoms of autism. Rfwd2+/- male mice showed deficits in social interaction and communication, increased repetitive and anxiety-like behavior, and spatial memory deficits, whereas Rfwd2+/- female mice showed subtle deficits in social communication and spatial memory but were normal in anxiety-like, repetitive, and social behaviors. These autistic-like behaviors in males were accompanied by a reduction in dendritic spine density and abnormal synaptic function on layer II/III pyramidal neurons in the prelimbic area of the medial prefrontal cortex (mPFC), as well as decreased expression of synaptic proteins. Impaired social behaviors in Rfwd2+/- male mice were rescued by the expression of ETV5, one of the major substrates of RFWD2, in the mPFC. These findings indicate an important role of RFWD2 in the pathogenesis of autism.

2.
J Exp Bot ; 74(18): 5564-5590, 2023 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-37478311

RESUMO

The ureides allantoin and allantoate serve as nitrogen (N) transport compounds in plants, and more recently, allantoin has been shown to play a role in signaling. In planta, tissue ureide levels are controlled by the activity of enzymes of the purine degradation pathway and by ureide transporters called ureide permeases (UPS). Little is known about the physiological function of UPS proteins in crop plants, and especially in monocotyledon species. Here, we identified 13 TaUPS genes in the wheat (Triticum aestivum L.) genome. Phylogenetic and genome location analyses revealed a close relationship of wheat UPSs to orthologues in other grasses and a division into TaUPS1, TaUPS2.1, and TaUPS2.2 groups, each consisting of three homeologs, with a total of four tandem duplications. Expression, localization, and biochemical analyses resolved spatio-temporal expression patterns of TaUPS genes, transporter localization at the plasma membrane, and a role for TaUPS2.1 proteins in cellular import of ureides and phloem and seed loading. In addition, positive correlations between TaUPS1 and TaUPS2.1 transcripts and ureide levels were found. Together the data support that TaUPSs function in regulating ureide pools at source and sink, along with source-to-sink transport. Moreover, comparative studies between wheat cultivars grown at low and high N strengthened a role for TaUPS1 and TaUPS2.1 transporters in efficient N use and in controlling primary metabolism. Co-expression, protein-protein interaction, and haplotype analyses further support TaUPS involvement in N partitioning, N use efficiency, and domestication. Overall, this work provides a new understanding on UPS transporters in grasses as well as insights for breeding resilient wheat varieties with improved N use efficiency.


Assuntos
Alantoína , Proteínas de Membrana Transportadoras , Alantoína/metabolismo , Proteínas de Membrana Transportadoras/genética , Proteínas de Membrana Transportadoras/metabolismo , Triticum/genética , Triticum/metabolismo , Nitrogênio/metabolismo , Filogenia , Melhoramento Vegetal
3.
Int J Mol Sci ; 24(2)2023 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-36674721

RESUMO

Klotho (KL) is a glycosyl hydrolase and aging-suppressor gene. Stress is a risk factor for depression and anxiety, which are highly comorbid with each other. The aim of this study is to determine whether KL is regulated by estrogen and plays an important role in sex differences in stress resilience. Our results showed that KL is regulated by estrogen in rat hippocampal neurons in vivo and in vitro and is essential for the estrogen-mediated increase in the number of presynaptic vesicular glutamate transporter 1 (Vglut1)-positive clusters on the dendrites of hippocampal neurons. The role of KL in sex differences in stress response was examined in rats using 3-week chronic unpredictable mild stress (CUMS). CUMS produced a deficit in spatial learning and memory, anhedonic-like behaviors, and anxiety-like behaviors in male but not female rats, which was accompanied by a reduction in KL protein levels in the hippocampus of male but not female rats. This demonstrated the resilience of female rats to CUMS. Interestingly, the knockdown of KL protein levels in the rat hippocampus of both sexes caused a decrease in stress resilience in both sexes, especially in female rats. These results suggest that the regulation of KL by estrogen plays an important role in estrogen-mediated synapse formation and that KL plays a critical role in the sex differences in cognitive deficit, anhedonic-like behaviors, and anxiety-like behaviors induced by chronic stress in rats, highlighting an important role of KL in sex differences in stress resilience.


Assuntos
Depressão , Caracteres Sexuais , Ratos , Animais , Masculino , Feminino , Depressão/metabolismo , Ansiedade , Transtornos de Ansiedade/metabolismo , Hipocampo/metabolismo , Estresse Psicológico/metabolismo , Modelos Animais de Doenças , Estrogênios/metabolismo
4.
Proc Natl Acad Sci U S A ; 116(40): 20169-20179, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31455734

RESUMO

Despite accumulating evidence demonstrating the essential roles played by neuropeptides, it has proven challenging to use this information to develop therapeutic strategies. Peptidergic signaling can involve juxtacrine, paracrine, endocrine, and neuronal signaling, making it difficult to define physiologically important pathways. One of the final steps in the biosynthesis of many neuropeptides requires a single enzyme, peptidylglycine α-amidating monooxygenase (PAM), and lack of amidation renders most of these peptides biologically inert. PAM, an ancient integral membrane enzyme that traverses the biosynthetic and endocytic pathways, also affects cytoskeletal organization and gene expression. While mice, zebrafish, and flies lacking Pam (PamKO/KO ) are not viable, we reasoned that cell type-specific elimination of Pam expression would generate mice that could be screened for physiologically important and tissue-specific deficits. Conditional PamcKO/cKO mice, with loxP sites flanking the 2 exons deleted in the global PamKO/KO mouse, were indistinguishable from wild-type mice. Eliminating Pam expression in excitatory forebrain neurons reduced anxiety-like behavior, increased locomotor responsiveness to cocaine, and improved thermoregulation in the cold. A number of amidated peptides play essential roles in each of these behaviors. Although atrial natriuretic peptide (ANP) is not amidated, Pam expression in the atrium exceeds levels in any other tissue. Eliminating Pam expression in cardiomyocytes increased anxiety-like behavior and improved thermoregulation. Atrial and serum levels of ANP fell sharply in PAM myosin heavy chain 6 conditional knockout mice, and RNA sequencing analysis identified changes in gene expression in pathways related to cardiac function. Use of this screening platform should facilitate the development of therapeutic approaches targeted to peptidergic pathways.


Assuntos
Peptídeos/metabolismo , Transdução de Sinais , Animais , Pressão Sanguínea , Regulação da Temperatura Corporal/genética , Regulação da Expressão Gênica , Hipocampo/fisiologia , Locomoção , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Oxigenases de Função Mista/genética , Oxigenases de Função Mista/metabolismo , Complexos Multienzimáticos/genética , Complexos Multienzimáticos/metabolismo , Neurônios/metabolismo , Neuropeptídeos/genética , Neuropeptídeos/metabolismo , Peptídeos/genética , Fenótipo
5.
J Exp Bot ; 72(12): 4435-4456, 2021 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-33829261

RESUMO

The effective use of available nitrogen (N) to improve crop grain yields provides an important strategy to reduce environmental N pollution and promote sustainable agriculture. However, little is known about the common genetic basis of N use efficiency (NUE) at varying N availability. Two wheat (Triticum aestivum L.) cultivars were grown in the field with high, moderate, and low N supply. Cultivar Zhoumai 27 outperformed Aikang 58 independent of the N supply and showed improved growth, canopy leaf area index, flag leaf surface area, grain number, and yield, and enhanced NUE due to both higher N uptake and utilization efficiency. Further, transcriptome and proteome analyses were performed using flag leaves that provide assimilates for grain growth. The results showed that many genes or proteins that are up- or down-regulated under all N regimes are associated with N and carbon metabolism and transport. This was reinforced by cultivar differences in photosynthesis, assimilate phloem transport, and grain protein/starch yield. Overall, our study establishes that improving NUE at both high and low N supply requires distinct adjustments in leaf metabolism and assimilate partitioning. Identified key genes/proteins may individually or concurrently regulate NUE and are promising targets for maximizing crop NUE irrespective of the N supply.


Assuntos
Nitrogênio , Triticum , Grão Comestível , Proteômica , Transcriptoma , Triticum/genética
6.
Int J Mol Sci ; 22(20)2021 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-34681741

RESUMO

Glutamine synthetase (GS), a key enzyme in plant nitrogen metabolism, is closely related to nitrogen remobilization. However, how GS isoforms participate in nitrogen remobilization remains unclear. Here, the spatiotemporal expression of the TaGS gene family after anthesis was investigated, and the results showed that TaGS1;1 was mainly encoded by TaGS1;1-6A, while the other isozymes were mainly encoded by TaGS localized on the A and D subgenomes. TaGS1;2-4A/4D had the highest expression level, especially in rachis and peduncle. Furthermore, immunofluorescence showed TaGS1;2 was located in the phloem of rachis and peduncle. GUS (ß-glucuronidase) staining confirmed that ProTaGS1;2-4A/4D::GUS activity was mainly present in the vascular system of leaves, roots, and petal of Arabidopsis. Ureides, an important transport form of nitrogen, were mainly synthesized in flag leaves and transported to grains through the phloem of peduncle and rachis during grain filling. TaAAH, which encodes the enzyme that degrades ureides to release NH4+, had a higher expression in rachis and peduncle and was synchronized with the increase in NH4+ concentration in phloem, indicating that NH4+ in phloem is from ureide degradation. Taking the above into account, TaGS1;2, which is highly expressed in the phloem of peduncle and rachis, may participate in N remobilization by assimilating NH4+ released from ureide degradation.


Assuntos
Glutamato-Amônia Ligase/genética , Glutamato-Amônia Ligase/metabolismo , Nitrogênio/metabolismo , Proteínas de Plantas/metabolismo , Triticum/metabolismo , Amônia/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas , Família Multigênica , Floema/metabolismo , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Regiões Promotoras Genéticas , Triticum/genética
7.
Mol Psychiatry ; 24(9): 1369-1382, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-30899091

RESUMO

Alzheimer's disease (AD) is characterized by the presence of neuritic plaques in which dystrophic neurites (DNs) are typical constituents. We recently showed that DNs labeled by antibodies to the tubular endoplasmic reticulum (ER) protein reticulon-3 (RTN3) are enriched with clustered tubular ER. However, multi-vesicle bodies are also found in DNs, suggesting that different populations of DNs exist in brains of AD patients. To understand how different DNs evolve to surround core amyloid plaques, we monitored the growth of DNs in AD mouse brains (5xFAD and APP/PS1ΔE9 mice) by multiple approaches, including two-dimensional and three-dimensional (3D) electron microscopy (EM). We discovered that a pre-autophagosome protein ATG9A was enriched in DNs when a plaque was just beginning to develop. ATG9A-positive DNs were often closer to the core amyloid plaque, whereas RTN3 immunoreactive DNs were mostly located in the outer layers of ATG9A-positive DNs. Proteins such as RAB7 and LC3 appeared in DNs at later stages during plaque growth, likely accumulated as a part of large autophagy vesicles, and were distributed relatively furthest from the core amyloid plaque. Reconstructing the 3D structure of different morphologies of DNs revealed that DNs in AD mouse brains were constituted in three layers that are distinct by enriching different types of vesicles, as validated by immune-EM methods. Collectively, our results provide the first evidence that DNs evolve from dysfunctions of pre-autophagosomes, tubular ER, mature autophagosomes, and the ubiquitin proteasome system during plaque growth.


Assuntos
Doença de Alzheimer/metabolismo , Neuritos/patologia , Distrofias Neuroaxonais/patologia , Doença de Alzheimer/fisiopatologia , Precursor de Proteína beta-Amiloide/metabolismo , Animais , Proteínas Relacionadas à Autofagia/metabolismo , Encéfalo/metabolismo , Modelos Animais de Doenças , Retículo Endoplasmático/metabolismo , Humanos , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Transgênicos , Proteínas do Tecido Nervoso/metabolismo , Distrofias Neuroaxonais/classificação , Distrofias Neuroaxonais/diagnóstico por imagem , Placa Amiloide/metabolismo , Proteínas de Transporte Vesicular/metabolismo
9.
Stress ; 23(3): 318-327, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31556781

RESUMO

D2 receptors (D2Rs) located in both pre- and postsynaptic membranes of medium spiny neurons (MSNs) in the nucleus accumbens (NAc) are involved in the stress response and associated behaviors. The role of D2Rs in chronic unpredictable stress (CUS)-induced depression-like behaviors is not clear. Quinpirole (a D2R agonist) and eticlopride (a D2R antagonist) were stereotactically delivered into the NAc before Sprague Dawley rats underwent CUS. CUS-induced depression-like behaviors were accompanied by a significant decrease in both the dopamine (DA) level and D2R expression in the NAc. Eticlopride reversed CUS-induced depression-like behavior and rescued the DA levels in the NAc, and microinjection of DA into the NAc of CUS individuals had the same effect as eticlopride. By contrast, delivery of quinpirole into the NAc of control animals induced depression-like behaviors accompanied by a decrease in the DA level in the NAc. These results show that DA plays a key role in CUS-induced depression-like behaviors and the D2R exerts a presynaptic negative feedback on DA levels during CUS. Microinjection of quinpirole into the NAc also decreased the level of the kalirin-7 protein in the NAc of both control and stressed animals, while eticlopride increased its level in the NAc of rats. In agreement with these results, intraperitoneal injection of eticlopride in mice also caused an increase in both the kalirin-7 protein level in the NAc and spine density in MSNs, while quinpirole reduced them. These results suggest that regulation of kalirin-7 through D2R in the NAc is a general pathway in rats and mice, and is involved in CUS-induced depression-like behaviors. Kalirin-7 may be directly regulated through the D2R postsynaptic pathway or indirectly through the presynaptic pathway in the NAc. The interaction between D2R and kalirin-7 needs to be investigated further.


Assuntos
Depressão , Estresse Psicológico , Animais , Depressão/tratamento farmacológico , Depressão/etiologia , Fatores de Troca do Nucleotídeo Guanina , Camundongos , Núcleo Accumbens/metabolismo , Quimpirol/farmacologia , Ratos , Ratos Sprague-Dawley , Receptores de Dopamina D2/metabolismo
10.
Endocr Res ; 45(2): 84-101, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31608702

RESUMO

Estrogen (E2) modulates a wide range of neural functions such as spine formation, synaptic plasticity, and neurotransmission in the hippocampus. Dendritic spines and synapse numbers in hippocampal neurons of female rats cyclically fluctuate across the estrous cycle, but the key genes responsible for these fluctuations are still unknown. In order to address this question, we explore the hippocampal transcriptome via RNA-sequencing (RNA-seq) at the proestrus (PE) and estrus (ES) stages in female rats. At standard fold-change selection criteria, 37 differentially expressed genes (DEGs) were found in PE vs. ES groups (FDR adjusted p-value (q)<0.05). The transcriptional changes identified by RNA-seq were confirmed by quantitative real-time PCR. To gain insight into the function of the DEGs, the E2-regulated genes were annotated by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes database (KEGG). Based on GO and KEGG pathways, the identified DEGs of PE vs. ES stages are involved in extracellular matrix formation, regulation of actin cytoskeleton, oxidative stress, neuroprotection, immune system, oligodendrocyte maturation and myelination, signal transduction pathways, growth factor signaling, retinoid signaling, aging, cellular process, metabolism and transport. The profiles of the gene expression in the hippocampus identified at the PE vs. ES stages were compared with the gene expression profiles in ovariectomized (OVX) rats receiving E2 replacement via RNA-seq and qPCR. The profiles of gene expression between the OVX+E2 and the estrous cycle were different and the possible causes were discussed.


Assuntos
Estradiol/metabolismo , Ciclo Estral/metabolismo , Perfilação da Expressão Gênica , Hipocampo/metabolismo , Animais , Feminino , Ratos , Análise de Sequência de RNA
11.
Int J Mol Sci ; 21(17)2020 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-32878133

RESUMO

Glutamine synthetase (GS), the key enzyme in plant nitrogen assimilation, is strictly regulated at multiple levels, but the most relevant reports focus on the mRNA level. Using specific antibodies as probes, the effects of nitrogen on the expression and localization of individual wheat GS (TaGS) isoforms were studied. In addition to TaGS2, TaGS1;1 with high affinity to substrate and TaGS1;3 with high catalytic activity were also localized in mesophyll, and may participate in cytoplasmic assimilation of ammonium (NH4+) released from photorespiration or absorbed by roots; TaGS1;2 was localized in xylem of leaves. In roots, although there were hundreds of times more TaGS1;1 than TaGS1;2 transcripts, the amount of TaGS1;1 subunit was not higher than that of TaGS1;2; NH4+ inhibited TaGS1;1 expression but stimulated TaGS1;3 expression. In root tips, nitrate stimulated TaGS1;1, TaGS1;3, and TaGS2 expression in meristem, while NH4+ promoted tissue differentiation and TaGS1;2 expression in endodermis and vascular tissue. Only TaGS1;2 was located in vascular tissue of leaves and roots, and was activated by glutamine, suggesting a role in nitrogen transport. TaGS1;3 was induced by NH4+ in root endodermis and mesophyll, suggesting a function in relieving NH4+ toxicity. Thus, TaGS isoforms play distinct roles in nitrogen assimilation for their different kinetic properties, tissue locations, and response to nitrogen regimes.


Assuntos
Regulação Enzimológica da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Glutamato-Amônia Ligase/metabolismo , Nitrogênio/metabolismo , Proteínas de Plantas/metabolismo , Triticum/enzimologia , Glutamato-Amônia Ligase/genética , Isoenzimas , Folhas de Planta/enzimologia , Proteínas de Plantas/genética
12.
Biochem Biophys Res Commun ; 509(2): 603-610, 2019 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-30606481

RESUMO

MicroRNA-135a-5p has been reported to play a potential role in the generation of new neurons. However, the underlying targets of miR-135a-5p in regulating neuronal differentiation have been poorly understood. Our study recently has uncovered that Sox6 and CD44 genes were significantly downregulated during neuronal differentiation of P19 cells, a multipotent cell type. We then found that Sox6 directly bound to the promoter of CD44. Importantly, we identified Sox6 as a direct target of miR-135a-5p. Additionally, we demonstrated that miR-135a-5p is crucial for the neuronal differentiation of P19 cells. More significantly, we found that Sox6 overexpression could overturn miR-135a-5p-mediated neuronal differentiation and dendrite development. In conclusion, these findings indicated that miR-135a-5p/Sox6/CD44 axis provides an important molecular target mechanism for neurodifferentiation.


Assuntos
Células-Tronco de Carcinoma Embrionário/patologia , Receptores de Hialuronatos/genética , MicroRNAs/genética , Neurogênese , Fatores de Transcrição SOXD/genética , Animais , Linhagem Celular Tumoral , Células-Tronco de Carcinoma Embrionário/citologia , Células-Tronco de Carcinoma Embrionário/metabolismo , Regulação Neoplásica da Expressão Gênica , Células HEK293 , Humanos , Receptores de Hialuronatos/metabolismo , Camundongos , Fatores de Transcrição SOXD/metabolismo , Transdução de Sinais
13.
Neurochem Res ; 44(5): 1243-1251, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30875016

RESUMO

A majority of excitatory synapses in the brain are localized on the dendritic spines. Alterations of spine density and morphology are associated with many neurological diseases. Understanding the molecular mechanisms underlying spine formation is important for understanding these diseases. Kalirin7 (Kal-7) is localized to the postsynaptic side of excitatory synapses in the neurons. Overexpression of Kal-7 causes an increase in spine density whereas knockdown expression of endogenous Kal-7 results in a decrease in spine density in primary cultured cortical neurons. However, the mechanisms underlying Kal-7-mediated spine formation are not entirely clear. Cyclin-dependent kinase 5 (Cdk5) plays a vital role in the formation of spines and synaptic plasticity. Kal-7 is phosphorylated by CDK5 at Thr1590, the unique Cdk5 phosphorylation site in the Kal-7 protein. This study was to explore the role of CDK5-mediated phosphorylation of Kal-7 in spine formation and the underlying mechanisms. Our results showed expression of Kal-7T/D (mimicked phosphorylation), Kal-7T/A mutants (blocked phosphorylation) or wild-type (Wt) Kal-7 caused in a similar increase in spine density, while spine size of Wt Kal-7-expressing cortical neurons was bigger than that in Kal-7 T\A-expressing neurons, but smaller than that in Kal-7T/D-expressing neurons. The fluorescence intensity of NMDA receptor subunit NR2B (GluN2B) staining was stronger along the MAP2 positive dendrites of Kal-7T/D-expressing neurons than that in Kal-7T/A- or Wt Kal-7-expressing neurons. The fluorescence intensity of AMPA receptor subunit GluR1 (GluA1) staining showed the same trend as GluN2B staining. These findings suggest that Cdk5 affects the function of Kal-7 on spine morphology and function via GluN2B and GluA1 receptors during dendritic spine formation.


Assuntos
Quinase 5 Dependente de Ciclina/metabolismo , Dendritos/metabolismo , Espinhas Dendríticas/metabolismo , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Animais , Hipocampo/metabolismo , Neurogênese/fisiologia , Plasticidade Neuronal/fisiologia , Neurônios/metabolismo , Sinapses/metabolismo
14.
Biochem Biophys Res Commun ; 505(3): 898-904, 2018 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-30309657

RESUMO

Major depression is a highly prevalent disorder with no effective medical treatments available. Recent evidence has shown that sirtuins (SIRTs) signaling has been implicated to play an essential in the pathogenesis of depression. Here in this study, we aimed to investigate the potential role of the phencynonate hydrochloride (PHH) in rat models of chronic unpredictable mild stress (CUMS)-induced depression. SIRT6 expression was up-regulated by PHH via increasing NAD+/NADH ratio in the prefrontal cortex. PHH was able to suppress CUMS-induced oxidative stress and enhance the antioxidant capacity and antioxidant proteins activity, such as superoxide dismutase 2 (SOD2) and peroxiredoxin 6 (Prdx6). In vitro study, we found that SIRT6 directly bound to SOD2 and Prdx6 and deacetylated them at Lys68/122 and Lys63/209, which were acetylated by p300/CBP-associated factor (PCAF). Finally, we showed that PHH ameliorated CUMS-induced depressive phenotypes by up-regulating SIRT6 deacetylation activity. In summary, PHH-mediating SIRT6 pathway is required for antidepressant response and PHH can be used as a novel therapeutic to effectively treat depression.


Assuntos
Compostos Aza/farmacologia , Glicolatos/farmacologia , Peroxirredoxina VI/metabolismo , Sirtuínas/metabolismo , Superóxido Dismutase/metabolismo , Acetilação , Animais , Antidepressivos/farmacologia , Compostos Aza/uso terapêutico , Depressão/tratamento farmacológico , Depressão/etiologia , Glicolatos/uso terapêutico , Ratos , Estresse Psicológico/complicações , Estresse Psicológico/tratamento farmacológico
15.
Neural Plast ; 2016: 8056370, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26881133

RESUMO

Depression, a severe psychiatric disorder, has been studied for decades, but the underlying mechanisms still remain largely unknown. Depression is closely associated with alterations in dendritic spine morphology and spine density. Therefore, understanding dendritic spines is vital for uncovering the mechanisms underlying depression. Several chronic stress models, including chronic restraint stress (CRS), chronic unpredictable mild stress (CUMS), and chronic social defeat stress (CSDS), have been used to recapitulate depression-like behaviors in rodents and study the underlying mechanisms. In comparison with CRS, CUMS overcomes the stress habituation and has been widely used to model depression-like behaviors. CSDS is one of the most frequently used models for depression, but it is limited to the study of male mice. Generally, chronic stress causes dendritic atrophy and spine loss in the neurons of the hippocampus and prefrontal cortex. Meanwhile, neurons of the amygdala and nucleus accumbens exhibit an increase in spine density. These alterations induced by chronic stress are often accompanied by depression-like behaviors. However, the underlying mechanisms are poorly understood. This review summarizes our current understanding of the chronic stress-induced remodeling of dendritic spines in the hippocampus, prefrontal cortex, orbitofrontal cortex, amygdala, and nucleus accumbens and also discusses the putative underlying mechanisms.


Assuntos
Encéfalo/fisiopatologia , Espinhas Dendríticas/fisiologia , Transtorno Depressivo/fisiopatologia , Modelos Animais de Doenças , Plasticidade Neuronal , Estresse Psicológico/complicações , Animais , Encéfalo/metabolismo , Espinhas Dendríticas/metabolismo , Transtorno Depressivo/etiologia , Transtorno Depressivo/metabolismo , Feminino , Humanos , Masculino , Camundongos , Ratos , Restrição Física
16.
J Exp Bot ; 66(21): 6827-34, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26307137

RESUMO

Glutamine synthetase (GS; EC 6.3.1.2) plays a crucial role in the assimilation and re-assimilation of ammonia derived from a wide variety of metabolic processes during plant growth and development. Here, three developmentally regulated isoforms of GS holoenzyme in the leaf of wheat (Triticum aestivum L.) seedlings are described using native-PAGE with a transferase activity assay. The isoforms showed different mobilities in gels, with GSII>GSIII>GSI. The cytosolic GSI was composed of three subunits, GS1, GSr1, and GSr2, with the same molecular weight (39.2kDa), but different pI values. GSI appeared at leaf emergence and was active throughout the leaf lifespan. GSII and GSIII, both located in the chloroplast, were each composed of a single 42.1kDa subunit with different pI values. GSII was active mainly in green leaves, while GSIII showed brief but higher activity in green leaves grown under field conditions. LC-MS/MS experiments revealed that GSII and GSIII have the same amino acid sequence, but GSII has more modification sites. With a modified blue native electrophoresis (BNE) technique and in-gel catalytic activity analysis, only two GS isoforms were observed: one cytosolic and one chloroplastic. Mass calibrations on BNE gels showed that the cytosolic GS1 holoenzyme was ~490kDa and likely a dodecamer, and the chloroplastic GS2 holoenzyme was ~240kDa and likely a hexamer. Our experimental data suggest that the activity of GS isoforms in wheat is regulated by subcellular localization, assembly, and modification to achieve their roles during plant development.


Assuntos
Glutamato-Amônia Ligase/química , Proteínas de Plantas/química , Triticum/química , Peso Molecular , Eletroforese em Gel de Poliacrilamida Nativa , Folhas de Planta/química , Isoformas de Proteínas/química , Corantes de Rosanilina
17.
BMC Cancer ; 15: 848, 2015 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-26537356

RESUMO

BACKGROUND: Liquid-state specimen carriers are inadequate for sample transportation in large-scale screening projects in low-resource settings, which necessitates the exploration of novel non-hazardous solid-state alternatives. Studies investigating the feasibility and accuracy of a solid-state human papillomavirus (HPV) sampling medium in combination with different down-stream HPV DNA assays for cervical cancer screening are needed. METHODS: We collected two cervical specimens from 396 women, aged 25-65 years, who were enrolled in a cervical cancer screening trial. One sample was stored using DCM preservative solution and the other was applied to a Whatman Indicating FTA Elute® card (FTA card). All specimens were processed using three HPV testing methods, including Hybrid capture 2 (HC2), careHPV™, and Cobas®4800 tests. All the women underwent a rigorous colposcopic evaluation that included using a microbiopsy protocol. RESULTS: Compared to the liquid-based carrier, the FTA card demonstrated comparable sensitivity for detecting high grade Cervical Intraepithelial Neoplasia (CIN) using HC2 (91.7 %), careHPV™ (83.3 %), and Cobas®4800 (91.7 %) tests. Moreover, the FTA card showed a higher specificity compared to a liquid-based carrier for HC2 (79.5 % vs. 71.6 %, P = 0.015), comparable specificity for careHPV™ (78.1 % vs. 73.0 %, P > 0.05), but lower specificity for the Cobas®4800 test (62.4 % vs. 69.9 %, P = 0.032). Generally, the FTA card-based sampling medium's accuracy was comparable with that of liquid-based medium for the three HPV testing assays. CONCLUSIONS: FTA cards are a promising sample carrier for cervical cancer screening. With further optimization, it can be utilized for HPV testing in areas of varying economic development.


Assuntos
DNA Viral/genética , Detecção Precoce de Câncer/métodos , Papillomaviridae/genética , Infecções por Papillomavirus/diagnóstico , Displasia do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/diagnóstico , Adulto , Idoso , Estudos de Viabilidade , Feminino , Genótipo , Humanos , Pessoa de Meia-Idade , Infecções por Papillomavirus/virologia , Projetos Piloto , Reprodutibilidade dos Testes , Neoplasias do Colo do Útero/virologia , Esfregaço Vaginal , Displasia do Colo do Útero/virologia
18.
Sci Rep ; 14(1): 10385, 2024 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-38710786

RESUMO

The verified text data of wheat varieties is an important component of wheat germplasm information. To automatically obtain a structured description of the phenotypic and genetic characteristics of wheat varieties, the aim at solve the issues of fuzzy entity boundaries and overlapping relationships in unstructured wheat variety approval data, WGIE-DCWF (joint extraction model of wheat germplasm information entity relationship based on deep character and word fusion) was proposed. The encoding layer of the model deeply fused word semantic information and character information using the Transformer encoder of BERT. This allowed for the cascading fusion of contextual semantic feature information to achieve rich character vector representation and improve the recognition ability of entity features. The triple extraction layer of the model established a cascading pointer network, extracted the head entity, extracted the tail entity according to the relationship category, and decoded the output triplet. This approach improved the model's capability to extract overlapping relationships. The experimental results demonstrated that the WGIE-DCWF model performed exceptionally well on both the WGD (wheat germplasm dataset) and the public dataset DuIE. The WGIE-DCWF model not only achieved high performance on the evaluation datasets but also demonstrated good generalization. This provided valuable technical support for the construction of a wheat germplasm information knowledge base and is of great significance for wheat breeding, genetic research, cultivation management, and agricultural production.


Assuntos
Triticum , Triticum/genética , Semântica , Algoritmos
19.
Plant Methods ; 19(1): 77, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37528413

RESUMO

BACKGROUND: Grain count is crucial to wheat yield composition and estimating yield parameters. However, traditional manual counting methods are time-consuming and labor-intensive. This study developed an advanced deep learning technique for the segmentation counting model of wheat grains. This model has been rigorously tested on three distinct wheat varieties: 'Bainong 307', 'Xinmai 26', and 'Jimai 336', and it has achieved unprecedented predictive counting accuracy. METHOD: The images of wheat ears were taken with a smartphone at the late stage of wheat grain filling. We used image processing technology to preprocess and normalize the images to 480*480 pixels. A CBAM-HRNet wheat grain segmentation counting deep learning model based on the Convolutional Block Attention Module (CBAM) was constructed by combining deep learning, migration learning, and attention mechanism. Image processing algorithms and wheat grain texture features were used to build a grain counting and predictive counting model for wheat grains. RESULTS: The CBAM-HRNet model using the CBAM was the best for wheat grain segmentation. Its segmentation accuracy of 92.04%, the mean Intersection over Union (mIoU) of 85.21%, the category mean pixel accuracy (mPA) of 91.16%, and the recall rate of 91.16% demonstrate superior robustness compared to other models such as HRNet, PSPNet, DeeplabV3+ , and U-Net. Method I for spike count, which calculates twice the number of grains on one side of the spike to determine the total number of grains, demonstrates a coefficient of determination R2 of 0.85, a mean absolute error (MAE) of 1.53, and a mean relative error (MRE) of 2.91. In contrast, Method II for spike count involves summing the number of grains on both sides to determine the total number of grains, demonstrating a coefficient of determination R2 of 0.92, an MAE) of 1.15, and an MRE) of 2.09%. CONCLUSIONS: Image segmentation algorithm of the CBAM-HRNet wheat spike grain is a powerful solution that uses the CBAM to segment wheat spike grains and obtain richer semantic information. This model can effectively address the challenges of small target image segmentation and under-fitting problems in training. Additionally, the spike grain counting model can quickly and accurately predict the grain count of wheat, providing algorithmic support for efficient and intelligent wheat yield estimation.

20.
Microbiol Spectr ; 11(3): e0081423, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-37074200

RESUMO

A simple model of alternative microbiota in the developing intestinal environment has been highly desirable for the study of health and disease in the gut. The pattern of antibiotic depletion of natural gut microbes is necessary for this model. However, the effects and loci of antibiotic deletion of gut microbes remain unclear. In this study, a mixture of three proven broad-spectrum antibiotics was selected to study their effects on microbial deletions in the jejunum, ileum, and colon of mice. The 16S rRNA sequencing results showed that antibiotics significantly reduced colonic microbial diversity, with limited effects on the jejunum and ileum. At the level of microbial genera, only 93.38% of Burkholderia-Caballeronia-Paraburkholderia and 5.89% of Enterorhabdus were present in the colon after antibiotic treatment. However, such changes were not observed in the microbial composition of the jejunum and ileum. Our results suggest that the antibiotics depleted intestinal microorganisms by acting primarily in the colon and not in the small intestine (jejunum and ileum). IMPORTANCE Many studies have applied antibiotics to delete intestinal microbes to shape pseudosterile mouse models and further used for fecal microbial transplantation. However, few studies have explored the spatial location of antibiotic action in the intestine. This study shows that the selected antibiotics effectively deleted microbiota in the colon of mice, with limited effects on microbes in the jejunum and ileum. Our study provides guidance for the application of a mouse model of antibiotic deletion of intestinal microbes.


Assuntos
Antibacterianos , Microbioma Gastrointestinal , Animais , Camundongos , Antibacterianos/farmacologia , RNA Ribossômico 16S/genética , Intestino Delgado , Colo
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