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1.
Cereb Cortex ; 34(1)2024 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-38142289

RESUMO

Concerns about the potential neurotoxic effects of anesthetics on developing brain exist. When making clinical decisions, the timing and dosage of anesthetic exposure are critical factors to consider due to their associated risks. In our study, we investigated the impact of repeated anesthetic exposures on the brain development trajectory of a cohort of rhesus monkeys (n = 26) over their first 2 yr of life, utilizing longitudinal magnetic resonance imaging data. We hypothesized that early or high-dose anesthesia exposure could negatively influence structural brain development. By employing the generalized additive mixed model, we traced the longitudinal trajectories of brain volume, cortical thickness, and white matter integrity. The interaction analysis revealed that age and cumulative anesthetic dose were variably linked to white matter integrity but not to morphometric measures. Early high-dose exposure was associated with increased mean, axial, and radial diffusivities across all white matter regions, compared to late-low-dose exposure. Our findings indicate that early or high-dose anesthesia exposure during infancy disrupts structural brain development in rhesus monkeys. Consequently, the timing of elective surgeries and procedures that require anesthesia for children and pregnant women should be strategically planned to account for the cumulative dose of volatile anesthetics, aiming to minimize the potential risks to brain development.


Assuntos
Anestésicos , Substância Branca , Humanos , Animais , Criança , Feminino , Gravidez , Macaca mulatta , Imagem de Tensor de Difusão/métodos , Encéfalo , Imageamento por Ressonância Magnética , Substância Branca/patologia , Anestésicos/toxicidade
2.
Environ Res ; 241: 117615, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-37949289

RESUMO

BACKGROUND: Polybrominated diphenyl ethers (PBDEs) are a group of widely used chemicals and humans are exposed to them in their daily life. PBDEs exposure during pregnancy may have adverse effects on pregnant women and their fetuses. Nevertheless, limited information is available on the levels and determinants of PBDEs exposure in Chinese pregnant women. METHODS: The internal exposure levels of eight PBDEs (BDE-28, 47, 99, 100, 153, 154, 183, and 209) in placental samples of 1280 pregnant women from Zunyi birth cohort were analyzed using gas chromatography tandem mass spectrometry. All PBDEs concentrations were lipid adjusted (ng/g lw). Determinants of exposure were assessed by multivariable logistic regression model. RESULTS: Eight PBDE homologues were quantifiable in more than 70% of the samples. The highest median concentrations were found for BDE-209 (2.78 ng/g lw), followed by BDE-153 (1.00 ng/g lw) and BDE-183 (0.93 ng/g lw). The level of ΣPBDEs ranged from 0.90 to 308.78 ng/g lw, with a median concentration of 10.02 ng/g lw. Multivariate logistic regression analysis showed that maternal age older than 30 years old (OR: 1.59; 95% CI: 1.14, 2.23), pre-pregnancy obesity (1.51; 1.08, 2.10), home renovation within 2 years (1.43; 1.08, 1.91), spending more time outdoors during pregnancy (0.70; 0.55, 0.89), high consumption of fish/seafood (1.46; 1.13, 1.90) and eggs (1.44; 1.04, 2.00), male infant sex (1.69; 1.18, 2.42) were associated with PBDEs exposure. CONCLUSION: The study population is generally exposed to PBDEs, of which BDE-209 is the dominant congener, indicating extensive application of products containing deca-BDE mixtures. Maternal age, pre-pregnancy BMI, home decoration, average outdoor time during pregnancy, fish, seafood, eggs consumption, and fetal sex were exposure-determinning factors. This study contributes to the knowledge on region-specific PBDEs contamination in pregnant women and related risk factors.


Assuntos
Éteres Difenil Halogenados , Placenta , Lactente , Animais , Humanos , Feminino , Masculino , Gravidez , Adulto , Placenta/química , Éteres Difenil Halogenados/análise , Gestantes , China
3.
BMC Plant Biol ; 23(1): 218, 2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-37098475

RESUMO

BACKGROUND: Avena longiglumis Durieu (2n = 2x = 14) is a wild relative of cultivated oat (Avena sativa, 2n = 6x = 42) with good agronomic and nutritional traits. The plant mitochondrial genome has a complex organization and carries genetic traits of value in exploiting genetic resources, not least male sterility alleles used to generate F1 hybrid seeds. Therefore, we aim to complement the chromosomal-level nuclear and chloroplast genome assemblies of A. longiglumis with the complete assembly of the mitochondrial genome (mitogenome) based on Illumina and ONT long reads, comparing its structure with Poaceae species. RESULTS: The complete mitochondrial genome of A. longiglumis can be represented by one master circular genome being 548,445 bp long with a GC content of 44.05%. It can be represented by linear or circular DNA molecules (isoforms or contigs), with multiple alternative configurations mediated by long (4,100-31,235 bp) and medium (144-792 bp) size repeats. Thirty-five unique protein-coding genes, three unique rRNA genes, and 11 unique tRNA genes are identified. The mitogenome is rich in duplications (up to 233 kb long) and multiple tandem or simple sequence repeats, together accounting for more than 42.5% of the total length. We identify homologous sequences between the mitochondrial, plastid and nuclear genomes, including the exchange of eight plastid-derived tRNA genes, and nuclear-derived retroelement fragments. At least 85% of the mitogenome is duplicated in the A. longiglumis nuclear genome. We identify 269 RNA editing sites in mitochondrial protein-coding genes including stop codons truncating ccmFC transcripts. CONCLUSIONS: Comparative analysis with Poaceae species reveals the dynamic and ongoing evolutionary changes in mitochondrial genome structure and gene content. The complete mitochondrial genome of A. longiglumis completes the last link of the oat reference genome and lays the foundation for oat breeding and exploiting the biodiversity in the genus.


Assuntos
Avena , Genoma Mitocondrial , Avena/genética , Diploide , Genoma Mitocondrial/genética , Melhoramento Vegetal , Genoma de Planta/genética , Filogenia
4.
Mol Breed ; 43(5): 38, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37312752

RESUMO

The photosystem II (PSII) outer antenna LHCB3 protein plays critical roles in distributing the excitation energy and modulating the rate of state transition for photosynthesis. Here, OsLHCB3 knockdown mutants were produced using the RNAi system. Phenotypic analyses showed that OsLHCB3 knockdown led to pale green leaves and lower chlorophyll contents at both tillering and heading stages. In addition, mutant lines exhibited decreased non-photochemical quenching (NPQ) capacity and net photosynthetic rate (Pn) by downregulating the expression of PSII-related genes. Moreover, RNA-seq experiments were performed at both tillering and heading stages. The differentially expressed genes (DEGs) mainly involved in chlorophyll binding response to abscisic acid, photosystem II, response to chitin, and DNA-binding transcription factor. Besides, our transcriptomic and physiological data indicated that OsLHCB3 was essential for binding chlorophyll, but not for the metabolism of chlorophyll in rice. OsLHCB3 RNAi knockdown plants affected the expression of PS II-related genes, but not PS I-related genes. Overall, these results suggest that OsLHCB3 also plays vital roles in regulating photosynthesis and antenna proteins in rice as well as responses to environment stresses. Supplementary Information: The online version contains supplementary material available at 10.1007/s11032-023-01387-z.

5.
Occup Environ Med ; 80(1): 34-41, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36424171

RESUMO

OBJECTIVE: Our aim was to elucidate the polycyclic aromatic hydrocarbon (PAH) metabolites exposure levels of pregnant women in the underdeveloped region of Zunyi, southwest China. METHODS: Sociodemographic information was collected via questionnaires, and urine samples were collected at the same time. A total of 3047 pregnant women participated in the study. Gas chromatography/mass spectrometry was used to detect the urine concentrations of 10 PAH metabolites. A generalised linear model (GLM) was used to identify predictive factors of PAH metabolites. RESULTS: All PAH metabolites had a detection rate greater than 60% (67.21%-90.57%) except for 4-OH-PHE at 55.54%. The median concentrations were 0.02-0.11 µg/g Cre except for 1-OH-NAP, 2-OH-NAP, 2-OH-FLU and 9-OH-FLU (0.36-0.50 µg/g Cre). The cluster analysis identified the phenanthrene and fluorene metabolite clusters (containing no other metabolites), while naphthalene metabolites (1-OH-NAP, 2-OH-NAP) could not be clustered without other metabolites. GLM analysis identified that pregnant women with the following characteristics have high urinary concentration of PAH metabolites: overweight, in the last trimester of pregnancy, distance between their house and main traffic lines as <5 m, use fuel for cooking, passive smoking, renovated their residence for less than 3 years, middle family income and office workers. CONCLUSION: The results clarified pregnant women from the economically underdeveloped area could be the victims of PAHs. In addition, PAHs present a demographic and seasonal differential distribution, which will aid in the development of targeted interventions and reduce exposure to PAHs during pregnancy.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Feminino , Humanos , Gravidez , Gestantes , Monitoramento Ambiental/métodos , Biomarcadores/urina , China
6.
Genomics ; 114(6): 110506, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36265745

RESUMO

Tea plants are continuously confronted with a wide range of biotic and abiotic stressors in the field, which can occur concurrently or sequentially. To elucidate the molecular mechanisms in responses to such individual and combined stresses, we used RNAseq to compare the temporal changes in the transcriptome of Camellia sinensis to Ectropis oblique Prout alone or in combination with exposure to drought and heat. Compared with the individual stress, tea plants exhibit significant differences in transcriptome profiles under the combined stresses. Additionally, many unique genes exhibited significant differences in expression in individual and combined stress conditions. Our research showed novel insights into the molecular mechanisms of E. oblique Prout resistance in tea plants and provided a valuable resource for developing tea varieties with broad spectrum stress tolerance.


Assuntos
Camellia sinensis , Lepidópteros , Animais , Camellia sinensis/genética , Resposta ao Choque Térmico
7.
Plant Dis ; 2022 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-35549323

RESUMO

As a commonly traditional Chinese medicine, the perennial herb Dangshen (Codonopsis pilosula) has superior curative effects including regulating immunity, strengthening the spleen, and tonifying lungs (Bai et al. 2020). To imitate natural ecological conditions, plants were grown on hillside fields with stems prostrate on the ground, tangle-up with each other. In August 2020, leaf spots were observed on C. pilosula in Wutai county, Shanxi province, China, and indicated a high disease incidence (70%-80%) in investigated fields (6.67 ha). Small brown necrotic spots, occasionally enclosed by chlorotic halos, were observed on leaves, stems, and sepals. For identification of the pathogen, 15 small pieces (5×5 mm) of symptomatic tissues from 5 randomly-collected diseased plants were surface sterilized, placed on potato dextrose agar plates, and incubated for 4 d in darkness at 25 °C to obtain the colonies. Cultures were purified by single spore isolation from these colonies. A total of 15 isolates named as Dcp-3, and Dcp-5~Dcp-18 were recovered. They produced ovoid or obclavate spores with 15.9-57.5×9.1-20.1 µm in size, 1-6 transverse septa, and 0-4 longitudinal septa. The conidial chains with 4 to 6 spores had numerous secondary and occasionally tertiary chains on potato carrot agar plates. Because all isolates had identical morphological traits, five genes from the representative isolate Dcp-3, actin (ACT), Alternaria major allergen (Alt a1), plasma membrane ATPase (ATP), histone 3 (H3), and rDNA ITS, were amplified with primer pairs ACTDF1/ACTDR1, Alt-for/Alt-rev, ATPDF1/ATPDR1, H3-1a/H3-1b, and ITS1/ITS4, respectively (Hong et al. 2005; Lawrence et al. 2013; Ma et al. 2020). BLASTn searches indicated species of Dcp-3 could not be accurately confirmed by rDNA ITS, ATP, ACT, and Alt a1 (GenBank accession nos. OM334894, OM362504, OM326344, OM362500). Phylogenetic analysis showed it was most closely related to Alternaria alternata, A. arborescens, and A. tenuissima based on concatenated sequences of above four genes. The H3 sequence (OM362508) shared 100% homology with that of A. alternata (MN481948). The phylogenetic tree using H3 also confirmed Dcp-3 as A. alternata. Heathly, two-year-old C. pilosula were transplanted to a greenhouse. A surface-sterilized leaf was sprayed with 50 µL spore suspension (106 conidia/mL) of Dcp-3. A leaf sprayed with isometric sterile water was used as controls. Each treatment used six plants (five leaves per plant). Plants were covered with sterilized plastic bags and incubated at 22 ℃. The test was repeated twice. A week later, control leaves were healthy, but brown necrotic spots similar to field symptoms emerged on treated leaves. The A. alternata isolates were re-isolated from the border of lesions, and confirmed by morphological and molecular characteristics mentioned above, fulfilling Koch's postulates. Leaf spot of C. pilosula caused by Septoria codonopsidis has been reported in China (Wang et al. 2011). However, to our knowledge, this is the first report of A. alternata inciting leaf spot of C. pilosula in China. Our report would promote growers to enhance the field management and consider associated strategies on controlling Alternaria leaf spot of C. pilosula.

8.
Genomics ; 113(1 Pt 2): 908-918, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33164828

RESUMO

The tea plant is an essential economic plant in many countries. However, its growing season renders them vulnerable to stresses. To understand the transcriptomic influences of these stresses on tea plants, we sequenced and analyzed the transcriptomes under drought, high-temperature, and pest. Paralogs were identified by comparing 14 evolutionarily close genomes. The differentially expressed paralog (DEPs) genes were analyzed regarding single or multiple stresses, and 1075 of the 4111 DEPs were commonly found in all the stresses. The co-expression network of the DEPs and TFs indicated that genes of catechin biosynthesis were associated with most transcription factors specific to each stress. The genes playing a significant role in the late response to drought and pest stress mainly functioned in the early response to high-temperature. This study revealed the relationship between stress and regulation of QRM synthesis and the role of QRMs in response to these (a)biotic stresses.


Assuntos
Cafeína/biossíntese , Camellia sinensis/genética , Catequina/biossíntese , Redes Reguladoras de Genes , Estresse Fisiológico , Transcriptoma , Cafeína/genética , Camellia sinensis/metabolismo , Catequina/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
9.
Molecules ; 27(11)2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35684499

RESUMO

As important biomolecules in Camellia sinensis L., amino acids (AAs) are considered to contribute to the overall green tea sensory quality and undergo dynamic changes during growth. However, limited by analytical capacity, detailed AAs composition in different growth stages remains unclear. To address this question, we analyzed the dynamic changes of 23 AAs during leaf growth in Xinyang Mao Jian (XYMJ) green tea. Using amino acid analyzer, we demonstrated that most AAs are abundant on Pure Brightness Day and Grain Rain Day. After Grain Rain, 23 AAs decreased significantly. Further analysis shows that theanine has a high level on the day before Spring Equinox and Grain Rain, accounting for 44-61% of the total free AAs content in tea leaves. Glu, Pro, and Asp are the second most abundant AAs. Additionally, spinasterol and 22,23-dihydrospinasterol are first purified and identified in ethanol extract of XYMJ by silica gel column chromatography method. This study reveals the relationship between plucking days and the dynamic changes of AAs during the growth stage and proves the rationality of the traditional plucking days of XYMJ green tea.


Assuntos
Camellia sinensis , Fitosteróis , Aminoácidos/metabolismo , Camellia sinensis/química , Fitosteróis/análise , Folhas de Planta/química , Esteróis/análise , Chá/química
10.
Ann Neurol ; 88(6): 1132-1143, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32939785

RESUMO

OBJECTIVE: A recessive biallelic repeat expansion, (AAGGG)exp , in the RFC1 gene has been reported to be a frequent cause of late-onset ataxia. For cerebellar ataxia, neuropathy, and vestibular areflexia syndrome (CANVAS), the recessive biallelic (AAGGG)exp genotype was present in ~92% of cases. This study aimed to examine whether the pentanucleotide repeat (PNR) was related to multiple system atrophy (MSA), which shares a spectrum of symptoms with CANVAS. METHODS: In this study, we screened the pathogenic (AAGGG)exp repeat and 5 other PNRs in 104 Chinese sporadic adult-onset ataxia of unknown aetiology (SAOA) patients, 282 MSA patients, and 203 unaffected individuals. Multiple molecular genetic tests were used, including long-range polymerase chain reaction (PCR), repeat-primed PCR (RP-PCR), Sanger sequencing, and Southern blot. Comprehensive clinical assessments were conducted, including neurological examination, neuroimaging, nerve electrophysiology, and examination of vestibular function. RESULTS: We identified biallelic (AAGGG)exp in 1 SAOA patient and 3 MSA patients. Additionally, 1 MSA patient had the (AAGGG)exp /(AAAGG)exp genotype with uncertain pathogenicity. We also described the carrier frequency for different PNRs in our cohorts. Furthermore, we summarized the distinct phenotypes of affected patients, suggesting that biallelic (AAGGG)exp in RFC1 could be associated with MSA and should be screened routinely in the MSA diagnostic workflow. INTERPRETATION: Our results expanded the clinical phenotypic spectrum of RFC1-related disorders and raised the possibility that MSA might share the same genetic background as CANVAS, which is crucial for re-evaluating the current CANVAS and MSA diagnostic criteria. ANN NEUROL 2020;88:1132-1143.


Assuntos
Expansão das Repetições de DNA/genética , Atrofia de Múltiplos Sistemas/genética , Proteína de Replicação C/genética , Estudos de Casos e Controles , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Fenótipo
11.
Mov Disord ; 36(1): 216-224, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32991004

RESUMO

BACKGROUND: In polyglutamine (polyQ) disease, the investigation of the prediction of a patient's age at onset (AAO) facilitates the development of disease-modifying intervention and underpins the delay of disease onset and progression. Few polyQ disease studies have evaluated AAO predicted by machine-learning algorithms and linear regression methods. OBJECTIVE: The objective of this study was to develop a machine-learning model for AAO prediction in the largest spinocerebellar ataxia type 3/Machado-Joseph disease (SCA3/MJD) population from mainland China. METHODS: In this observational study, we introduced an innovative approach by systematically comparing the performance of 7 machine-learning algorithms with linear regression to explore AAO prediction in SCA3/MJD using CAG expansions of 10 polyQ-related genes, sex, and parental origin. RESULTS: Similar prediction performance of testing set and training set in each models were identified and few overfitting of training data was observed. Overall, the machine-learning-based XGBoost model exhibited the most favorable performance in AAO prediction over the traditional linear regression method and other 6 machine-learning algorithms for the training set and testing set. The optimal XGBoost model achieved mean absolute error, root mean square error, and median absolute error of 5.56, 7.13, 4.15 years, respectively, in testing set 1, with mean absolute error (4.78 years), root mean square error (6.31 years), and median absolute error (3.59 years) in testing set 2. CONCLUSION: Machine-learning algorithms can be used to predict AAO in patients with SCA3/MJD. The optimal XGBoost algorithm can provide a good reference for the establishment and optimization of prediction models for SCA3/MJD or other polyQ diseases. © 2020 International Parkinson and Movement Disorder Society.


Assuntos
Doença de Machado-Joseph , Ataxias Espinocerebelares , Idade de Início , China , Humanos , Doença de Machado-Joseph/genética , Aprendizado de Máquina , Ataxias Espinocerebelares/diagnóstico , Ataxias Espinocerebelares/genética
12.
Appl Opt ; 60(2): 459-464, 2021 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-33448972

RESUMO

A difference-fitting method is proposed to mitigate the low frequency drift of a phase-sensitive optical time domain reflectometry (Φ-OTDR) system caused by laser phase noise. The effective difference region for phase demodulation is theoretically analyzed and experimentally verified, which should be greater than the convolution of the spatial resolution and the length of disturbed optical fiber. Then, a median-fitting algorithm is used to obtain the phase noise of the differential region. The vibration signal of 0.2 Hz is first demodulated with the SNR of 41.79 dB on the optical fiber of 11 km. The low-frequency vibration signals of 0.05 Hz and 0.02 Hz are then successfully restored by using the difference-fitting method, which can effectively eliminate the influence of low frequency drift.

13.
BMC Plant Biol ; 20(1): 294, 2020 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-32600265

RESUMO

BACKGROUND: Catechins, caffeine, and theanine as three important metabolites in the tea leaves play essential roles in the formation of specific taste and shows potential health benefits to humans. However, the knowledge on the dynamic changes of these metabolites content over seasons, as well as the candidate regulatory factors, remains largely undetermined. RESULTS: An integrated transcriptomic and metabolomic approach was used to analyze the dynamic changes of three mainly metabolites including catechins, caffeine, and theanine, and to explore the potential influencing factors associated with these dynamic changes over the course of seasons. We found that the catechins abundance was higher in Summer than that in Spring and Autumn, and the theanine abundance was significantly higher in Spring than that in Summer and Autumn, whereas caffeine exhibited no significant changes over three seasons. Transcriptomics analysis suggested that genes in photosynthesis pathway were significantly down-regulated which might in linkage to the formation of different phenotypes and metabolites content in the tea leaves of varied seasons. Fifty-six copies of nine genes in catechins biosynthesis, 30 copies of 10 genes in caffeine biosynthesis, and 12 copies of six genes in theanine biosynthesis were detected. The correlative analysis further presented that eight genes can be regulated by transcription factors, and highly correlated with the changes of metabolites abundance in tea-leaves. CONCLUSION: Sunshine intensity as a key factor can affect photosynthesis of tea plants, further affect the expression of major Transcription factors (TFs) and structural genes in, and finally resulted in the various amounts of catechins, caffeine and theaine in tea-leaves over three seasons. These findings provide new insights into abundance and influencing factors of metabolites of tea in different seasons, and further our understanding in the formation of flavor, nutrition and medicinal function.


Assuntos
Cafeína/biossíntese , Camellia sinensis/metabolismo , Catequina/biossíntese , Glutamatos/biossíntese , Expressão Gênica , Metabolômica , Fenótipo , Folhas de Planta/metabolismo , Estações do Ano , Fatores de Transcrição/metabolismo , Transcriptoma
14.
J Immunol ; 200(8): 2869-2881, 2018 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-29514951

RESUMO

The emergence of adaptive immunity in jawed vertebrates depended on the appearance of variable immune receptors, BCRs and TCRs, which exhibit variable-J-constant (VJ-C)-type Ig superfamily folds. Hitherto, however, the structures of IgV-J-IgC-type molecules had never been characterized in invertebrates, leaving the origin of BCR/TCR-type molecules unknown. Using x-ray crystallography, the structure of a VJ-C2 molecule, named AmpIgVJ-C2, was determined in amphioxus (Branchiostoma floridae). The first domain shows typical V folding, including the hydrophobic core, CDR analogs, and eight conserved residues. The second domain is a C2-type Ig superfamily domain, as defined by its short length and the absence of ß-strand D- and C1-typical motifs. AmpIgVJ-C2 molecules form homodimers, using "three-layer packing dimerization," as described for TCRs and BCRs. The AmpIgVJ-C2 V domain harbors a diglycine motif in ß-strand G and forms a ß-bulge structure participating in V-V intermolecular interaction. By immunohistochemistry, AmpIgVJ-C2 molecules were primarily found in mucosal tissues, whereas PCR and sequence analysis indicated considerable genetic variation at the single-gene level; these findings would be consistent with an immune function and a basic ability to adapt to binding different immune targets. Our results show a BCR/TCR-ancestral like molecule in amphioxus and help us to understand the evolution of the adaptive immune system.


Assuntos
Domínios de Imunoglobulina/genética , Região Variável de Imunoglobulina/química , Anfioxos/imunologia , Receptores Imunológicos/química , Receptores Imunológicos/genética , Imunidade Adaptativa/fisiologia , Animais , Evolução Molecular , Anfioxos/genética
15.
Exp Cell Res ; 382(2): 111478, 2019 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-31233742

RESUMO

Small cell lung cancer (SCLC) has been a recalcitrant cancer without significant breakthroughs in clinical treatment during the past three decades. As there is a lack of effective protein inhibitor for SCLC targeted therapy, the discovery of new druggable SCLC biomarkers is a pressing work. Here we identified a new protein biomarker of SCLC, which is high density lipoprotein binding protein (HDLBP), through the aptamer generated by cell-SELEX against SCLC cells. Immunohistochemistry results showed an elevated HDLBP level in SCLC tissues from clinical samples. Attenuating HDLBP expression with siRNA inhibited proliferation and metastasis of SCLC cells in vitro and tumor formation in vivo. Mechanism study revealed the new function of HDLBP in promoting G1/S cell cycle transition for tumor progression. While the inhibitor of HDLBP has been reported, our work suggested a promising potential of targeting HDLBP to improve the treatment of fatal SCLC and a powerful tool of using cell-SELEX in cancer medicine.


Assuntos
Aptâmeros de Peptídeos/metabolismo , Biomarcadores Tumorais/metabolismo , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Técnica de Seleção de Aptâmeros , Carcinoma de Pequenas Células do Pulmão/metabolismo , Carcinoma de Pequenas Células do Pulmão/patologia , Linhagem Celular Tumoral , Progressão da Doença , Fase G1 , Humanos , Metástase Neoplásica , Fenótipo , Proteínas de Ligação a RNA/metabolismo , Reprodutibilidade dos Testes , Fase S
16.
Genomics ; 111(4): 619-628, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-29621573

RESUMO

Reactive oxygen species (ROS) are versatile signaling molecules in sensing stresses and play critical roles in signaling and development. Plasma membrane NADPH oxidases (NOXs) are key producers of ROS, and play important roles in the regulation of plant-pathogen interactions. Here, we performed a comprehensive analysis of the NOX gene family in the soybean genome (Glycine max) and 17 NOX (GmNOX) genes were identified. Structural analysis revealed that the GmNOX proteins in soybean were as conserved as those in other plants. 8 duplicated gene pairs were formed by a Glycine-specific whole-genome duplication (WGD) event approximately 13 million years ago (Mya). The Ka/Ks ratios of GmNOX genes ranged from 0.04 to 0.28, suggesting that the GmNOX family had undergone purifying selection in soybean. Gene expression patterns showed different expression of these duplicate genes, suggesting that the GmNOXs were retained by substantial subfunctionalization during the soybean evolutionary processes. Subsequently, the expression of GmNOXs in response to drought and phytohormones were characterized via qPCR. Importantly, four GmNOXs showed strong expression in nodules, pointing to their probable involvement in nodulation. Thus, our results shed light on the evolutionary history of this family in soybean and contribute to the functional characterization of GmNOX genes in soybean.


Assuntos
Evolução Molecular , Glycine max/genética , NADPH Oxidases/genética , Proteínas de Plantas/genética , Duplicação Gênica , Família Multigênica , NADPH Oxidases/metabolismo , Filogenia , Proteínas de Plantas/metabolismo , Glycine max/classificação
17.
Plant Mol Biol ; 100(3): 265-283, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30989446

RESUMO

KEY MESSAGE: Symbiotic nitrogen fixation in root nodules of grain legumes is essential for high yielding. Protein phosphorylation/dephosphorylation plays important role in root nodule development. Differences in the phosphoproteomes may either be developmental specific and related to nitrogen fixation activity. An iTRAQ-based quantitative phosphoproteomic analyses during nodule development enables identification of specific phosphorylation signaling in the Lotus-rhizobia symbiosis. During evolution, legumes (Fabaceae) have evolved a symbiotic relationship with rhizobia, which fix atmospheric nitrogen and produce ammonia that host plants can then absorb. Root nodule development depends on the activation of protein phosphorylation-mediated signal transduction cascades. To investigate possible molecular mechanisms of protein modulation during nodule development, we used iTRAQ-based quantitative proteomic analyses to identify root phosphoproteins during rhizobial colonization and infection of Lotus japonicus. 1154 phosphoproteins with 2957 high-confidence phosphorylation sites were identified. Gene ontology enrichment analysis of functional groups of these genes revealed that the biological processes mediated by these proteins included cellular processes, signal transduction, and transporter activity. Quantitative data highlighted the dynamics of protein phosphorylation during nodule development and, based on regulatory trends, seven groups were identified. RNA splicing and brassinosteroid (BR) signaling pathways were extensively affected by phosphorylation, and most Ser/Arg-rich (SR) proteins were multiply phosphorylated. In addition, many proposed kinase-substrate pairs were predicted, and in these MAPK6 substrates were found to be highly enriched. This study offers insights into the regulatory processes underlying nodule development, provides an accessible resource cataloging the phosphorylation status of thousands of Lotus proteins during nodule development, and develops our understanding of post-translational regulatory mechanisms in the Lotus-rhizobia symbiosis.


Assuntos
Fabaceae/metabolismo , Lotus/metabolismo , Proteínas de Plantas/metabolismo , Proteômica/métodos , Rhizobium/fisiologia , Nódulos Radiculares de Plantas/metabolismo , Transdução de Sinais , Simbiose/fisiologia , Amônia/metabolismo , Fabaceae/genética , Regulação da Expressão Gênica de Plantas , Lotus/genética , Espectrometria de Massas , Proteína Quinase 6 Ativada por Mitógeno/genética , Proteína Quinase 6 Ativada por Mitógeno/metabolismo , Fixação de Nitrogênio , Fosfoproteínas/fisiologia , Fosforilação , Proteínas de Plantas/genética , Raízes de Plantas/metabolismo , Splicing de RNA , RNA de Plantas/metabolismo , Rhizobium/genética , Nódulos Radiculares de Plantas/genética , Nódulos Radiculares de Plantas/crescimento & desenvolvimento , Fatores de Transcrição
18.
J Am Chem Soc ; 141(46): 18492-18499, 2019 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-31657561

RESUMO

Therapeutic target identification and corresponding drug development is a demanding task for the treatment of lung adenocarcinoma, especially the most malignant proximal-proliferative subtype without druggable protein kinase mutations. Using a cell-SELEX-generated aptamer, we discovered a new tumor driver protein, leucine-rich pentatricopeptide repeat-containing protein (LRPPRC), which is specifically overexpressed in the most lethal subtype of lung adenocarcinoma. Targeted LRPPRC protein knockdown is a promising therapeutic strategy for the undruggable LUAD (lung adenocarcinoma). Nevertheless, LRPPRC is mainly located in mitochondria and degraded by protease. Current protein knockdown approaches, such as proteolysis-targeting chimeras (PROTACs), have limitations in their applications to the proteins degraded through proteasome-independent ways. Here, we designed an aptamer-assisted high-throughput method to screen small molecules that could bind to LRPPRC directly, disrupt the interaction of LRPPRC with its stabilizing chaperon protein, and lead to LRPPRC degradation by mitochondrial protease. The screened compound, gossypolacetic acid (GAA), is an old medicine that can accomplish the new function for targeted LRPPRC knockdown. It showed significant antitumor effects even with the LRPPRC-positive patient-derived tumor xenograft (PDX) model. This work not only extended the application of aptamers to screen small-molecule inhibitors for the undruggable lung cancers, but more importantly provided a new strategy to develop protein knockdown methods beyond the proteasome system.


Assuntos
Adenocarcinoma de Pulmão/tratamento farmacológico , Antineoplásicos/farmacologia , Neoplasias Pulmonares/tratamento farmacológico , Proteínas/metabolismo , Bibliotecas de Moléculas Pequenas/farmacologia , Células A549 , Adenocarcinoma de Pulmão/metabolismo , Animais , Antineoplásicos/química , Antineoplásicos/uso terapêutico , Aptâmeros de Nucleotídeos/metabolismo , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Proteínas de Repetições Ricas em Leucina , Neoplasias Pulmonares/metabolismo , Camundongos Nus , Complexo de Endopeptidases do Proteassoma/metabolismo , Mapas de Interação de Proteínas/efeitos dos fármacos , Proteínas/antagonistas & inibidores , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/uso terapêutico
19.
Plant Biotechnol J ; 17(4): 826-835, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30256509

RESUMO

DNA methylation is essential for gene regulation, imprinting and silencing of transposable elements (TEs). Although bursts of transposable elements are common in many plant lineages, how plant DNA methylation is related to transposon bursts remains unclear. Here we explore the landscape of DNA methylation of tea, a species thought to have experienced a recent transposon burst event. This species possesses more transposable elements than any other sequenced asterids (potato, tomato, coffee, pepper and tobacco). The overall average DNA methylation levels were found to differ among the tea, potato and tomato genomes, and methylation at CHG sequence sites was found to be significantly higher in tea than that in potato or tomato. Moreover, the abundant TEs resulting from burst events not only resulted in tea developing a very large genome size, but also affected many genes involved in importantly biological processes, including caffeine, theanine and flavonoid metabolic pathway genes. In addition, recently transposed TEs were more heavily methylated than ancient ones, implying that DNA methylation is proportionate to the degree of TE silencing, especially on recent active ones. Taken together, our results show that DNA methylation regulates transposon silencing and may play a role in genome size expansion.


Assuntos
Camellia sinensis/genética , Epigenoma/genética , Regulação da Expressão Gênica de Plantas/genética , Genoma de Planta/genética , Metilação de DNA , Elementos de DNA Transponíveis/genética , Tamanho do Genoma/genética
20.
Int Microbiol ; 22(2): 227-237, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30810985

RESUMO

Chicken feather waste is generally insufficiently utilized despite its high content of protein, constituting an environmental issue. Biodegradation of the waste with enabling microbes provides an advantageous option among the available solutions. In this study, an efficient whole feather-degrading strain was strategically isolated from a soil sample taken from a local tea plantation that has little or nothing to do with feathers. The strain was identified as Bacillus thuringiensis (designated as FDB-10) according to the cloned complete 16S rRNA sequence. The FDB-10 could efficiently degrade briefly heat-treated whole feather (102 °C, 5 min; up to 90% of a maximum concentration of 30 g/L) in a salt medium supplemented with 0.1 g/L yeast extract within 24 h (37 °C, 150 rpm). Addition of carbon sources (glycerol, glucose, starch, Tween 20, Tween 80, 1.25 g/L as glycerol) to the fermentation medium could improve the degradation. However, significant inhibition could be observed when the added carbon source reached the amount usually adopted in the investigation of carbon source preference (1%). Nitrogen source (NH4Cl, (NH4)2SO4, peptone) adversely influenced the performance of the strain. When the molar concentrations of NH4+ were equal for the two salt, the inhibitory effect on degradation of whole feathers was similar. Entirely different from other reported feather-degrading strains showing a preference to melanin-free feather substrates, the strain isolated in this study could degrade melanin-containing feather equally efficiently, and higher protease activity could be detected in the digest mix. As a plus, the strain could degrade feathers in rice wash produced in daily cooking, indicating its potential use in the simultaneous treatment of rice cooker wastewater produced by a rice processing plant. All these results imply that the FDB-10 is a strain with great potential in the biodegradation of feather waste.


Assuntos
Bacillus thuringiensis/isolamento & purificação , Bacillus thuringiensis/metabolismo , Plumas/metabolismo , Microbiologia do Solo , Animais , Bacillus thuringiensis/classificação , Bacillus thuringiensis/genética , Biotransformação , Galinhas , Análise por Conglomerados , Meios de Cultura , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Fermentação , Resíduos Industriais , Queratinas/metabolismo , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Chá/crescimento & desenvolvimento , Temperatura
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