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Cytochrome P450 proteins (CYPs) play critical roles in plant development and adaptation to fluctuating environments. Previous reports have shown that CYP86A proteins are involved in the biosynthesis of suberin and cutin in Arabidopsis. However, the functions of these proteins in rice remain obscure. In this study, a rice mutant with incomplete male sterility was identified. Cytological analyses revealed that this mutant was defective in anther development. Cloning of the mutant gene indicated that the responsible mutation was on OsCYP86A9. OsMYB80 is a core transcription factor in the regulation of rice anther development. The expression of OsCYP86A9 was abolished in the anther of osmyb80 mutant. In vivo and in vitro experiments showed that OsMYB80 binds to the MYB-binding motifs in OsCYP86A9 promoter region and regulates its expression. Furthermore, the oscyp86a9 mutant exhibited an impaired suberin deposition in the root, and was more susceptible to drought stress. Interestingly, genetic and biochemical analyses revealed that OsCYP86A9 expression was regulated in the root by certain MYB transcription factors other than OsMYB80. Moreover, mutations in the MYB genes that regulate OsCYP86A9 expression in the root did not impair the male fertility of the plant. Taken together, these findings revealed the critical roles of OsCYP86A9 in plant development and proposed that OsCYP86A9 functions in anther development and root suberin formation via two distinct tissue-specific regulatory pathways.
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Regulação da Expressão Gênica de Plantas , Lipídeos , Oryza , Proteínas de Plantas , Fatores de Transcrição , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Flores/genética , Flores/crescimento & desenvolvimento , Flores/metabolismo , Lipídeos/biossíntese , Mutação , Oryza/genética , Oryza/crescimento & desenvolvimento , Oryza/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genéticaRESUMO
Cold stress is a major factor limiting the production and geographical distribution of rice (Oryza sativa) varieties. However, the molecular mechanisms underlying cold tolerance remain to be elucidated. Here, we report that ornithine δ-aminotransferase (OsOAT) contributes to cold tolerance during the vegetative and reproductive development of rice. osoat mutant was identified as a temperature-sensitive male sterile mutant with deformed floral organs and seedlings sensitive to cold stress. Comparative transcriptome analysis showed that OsOAT mutation and cold treatment of the wild-type plant led to similar changes in the global gene expression profiles in anthers. OsOAT genes in indica rice Huanghuazhan (HHZ) and japonica rice Wuyungeng (WYG) are different in gene structure and response to cold. OsOAT is cold-inducible in WYG but cold-irresponsive in HHZ. Further studies showed that indica varieties carry both WYG-type and HHZ-type OsOAT, whereas japonica varieties mostly carry WYG-type OsOAT. Cultivars carrying HHZ-type OsOAT are mainly distributed in low-latitude regions, whereas varieties carrying WYG-type OsOAT are distributed in both low- and high-latitude regions. Moreover, indica varieties carrying WYG-type OsOAT generally have higher seed-setting rates than those carrying HHZ-type OsOAT under cold stress at reproductive stage, highlighting the favorable selection for WYG-type OsOAT during domestication and breeding to cope with low temperatures.
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Oryza , Oryza/metabolismo , Melhoramento Vegetal , Desenvolvimento Vegetal , Transaminases/metabolismo , Fertilidade/genética , Ornitina/metabolismo , Temperatura BaixaRESUMO
BACKGROUND: Human papillomavirus (HPV) infection has become an important etiological driver of oropharyngeal squamous cell carcinoma (OPSCC), leading to unique tumor characteristics. However, the interplay between HPV-associated tumor cells and tumor microenvironment (TME) remains an enigma. METHODS: We performed a single-cell RNA-sequencing (scRNA-seq) on HPV-positive (HPV+) and HPV-negative (HPVâ) OPSCC tumors, each for three samples, and one normal tonsil tissue. Ex vivo validation assays including immunofluorescence staining, cell line co-culture, and flow cytometry analysis were used to test specific subtypes of HPV+ tumor cells and their communications with T cells. RESULTS: Through a comprehensive single-cell transcriptome analysis, we uncover the distinct transcriptional signatures between HPV+ and HPVâ OPSCC. Specifically, HPV+ OPSCC tumor cells manifest an enhanced interferon response and elevated expression of the major histocompatibility complex II (MHC-II), potentially bolstering tumor recognition and immune response. Furthermore, we identify a CXCL13+CD4+ T cell subset that exhibits dual features of both follicular and pro-inflammatory helper T cells. Noteworthily, HPV+ OPSCC tumor cells embrace extensive intercellular communications with CXCL13+CD4+ T cells. Interaction with HPV+ OPSCC tumor cells amplifies CXCL13 and IFNγ release in CD4+T cells, fostering a pro-inflammatory TME. Additionally, HPV+ tumor cells expressing high MHC-II and CXCL13+CD4+ T cell prevalence are indicative of favorable overall survival rates in OPSCC patients. CONCLUSIONS: Together, our study underscores a synergistic inflammatory immune response orchestrated by highly immunogenic tumor cells and CXCL13+CD4+ T cells in HPV+ OPSCC, offering useful insights into strategy development for patient stratification and effective immunotherapy in OPSCC.
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Linfócitos T CD4-Positivos , Quimiocina CXCL13 , Imunoterapia , Neoplasias Orofaríngeas , Infecções por Papillomavirus , Microambiente Tumoral , Humanos , Neoplasias Orofaríngeas/imunologia , Neoplasias Orofaríngeas/virologia , Neoplasias Orofaríngeas/terapia , Infecções por Papillomavirus/imunologia , Infecções por Papillomavirus/virologia , Infecções por Papillomavirus/complicações , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Quimiocina CXCL13/metabolismo , Quimiocina CXCL13/genética , Microambiente Tumoral/imunologia , Imunoterapia/métodos , Ativação Linfocitária/imunologia , Antígenos de Histocompatibilidade Classe II/imunologia , Antígenos de Histocompatibilidade Classe II/metabolismo , PapillomaviridaeRESUMO
Multi-directional polarized optical sensors are increasingly vital in passive remote sensing, deepening our understanding of global cloud properties. Nevertheless, uncertainty lingers on how these observations can contribute to our knowledge of cloud diversity. The variability in cloud PSD (Particle Size Distribution) significantly influences a wide array of cloud characteristics, while unidentified factors in RT (Radiative Transfer) may introduce errors into the cloud PSD retrieval algorithm. Therefore, establishing unified evaluation criteria for both optical device configuration and inversion methods is crucial. Our study, based on Bayesian theory and RT, assesses the information content of both cloud effective radius and effective variance retrieval, along with the key factors affecting their retrieval in multi-directional polarized observations, using the calculation of DFS (Degree of Freedom for Signals).We consider the process of solar incidence, cloud scattering, and sensor reception, and discuss the impact of various sensor configurations, cloud characteristics, and other components on the retrieval of cloud PSD. Correspondingly, we observed a 48% improvement in the information content of cloud PSD with the incorporation of multi-directional polarized measurements in the rainbow region. Cloud droplet concentration significantly influences inversion, but its PSD does not cause monotonic linear interference on information content. The blending of particle mixtures with different PSD has a significant negative impact on DFS. In cases where the AOD (Aerosol Optical Depth) is less than 0.5 and the COT (Cloud Optical Thickness) exceeds 5, the influence of aerosol and surface contributions on inversion can be neglected. Our findings would serve as a foundation for future instrument design improvements and enhancements to retrieval algorithms.
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Obesity is caused by an imbalance between energy intake and energy expenditure. This study aimed to determine the effects and mechanisms of 2',4'-dihydroxy-6'-methoxy-3',5'-dimethylchalcone (DMC) on exercise tolerance in high-fat diet (HFD)-fed mice. Male C57BL/6J mice were randomly divided into two categories (7 groups [n = 8]): sedentary (control [CON], HFD, 200 mg/kg DMC, and 500 mg/kg DMC) and swimming (HFD, 200 mg/kg DMC, and 500 mg/kg DMC). Except the CON group, all other groups were fed HFD with or without DMC intervention for 33 days. The swimming groups were subjected to exhaustive swimming (three sessions/week). Changes in swimming time, glucolipid metabolism, body composition, biochemical indicators, histopathology, inflammation, metabolic mediators, and protein expression were assessed. DMC combined with regular exercise improved endurance performance, body composition, glucose and insulin tolerance, lipid profile, and the inflammatory state in a dose-dependent manner. Further, DMC alone or combined with exercise could restore normal tissue morphology, reduce fatigue-associated markers, and boost whole-body metabolism and the protein expression of phospho-AMP-activated protein kinase alpha/total-AMP-activated protein kinase alpha (AMPK), sirtuin-1 (SIRT1), peroxisome-proliferator-activated receptor gamma coactivator 1alpha (PGC-1α), and peroxisome proliferator-activated receptor alpha in the muscle and adipose tissues of HFD-fed mice. DMC exhibits antifatigue effects by regulating glucolipid catabolism, inflammation, and energy homeostasis. Furthermore, DMC exerts a synergistic exercise-related metabolic effect via the AMPK-SIRT1-PGC-1α signaling pathway, suggesting that DMC is a potential natural sports supplement with mimicked or augmented exercise effects for obesity prevention.
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AIMS AND OBJECTIVES: To explore the acceptances and associated influences of organ donation in mainland China. BACKGROUND: The shortage of organ donors has limited the development of organ transplantation in China. It is important to recognise the target population who has high intention to donate their organs may change the status. DESIGN: We conducted a cross-sectional, multi-stage sampling study collected demographic data and individuals' willingness to accept organ donation. METHODS: A stepwise linear regression analysis was adopted to evaluate the factors related to the attitudes toward organ donation. RESULTS: We collected 11,031 valid samples for the survey. The willingness to donate organs among Chinese residents averaged 56.93 points. To be specific, males (ß = -.03), religious believers (ß = -.01) and parents with a different number of children (all: ß = -.04) are less willing to donate their organs. Respondents who live in an urban area (ß = .03), have higher education level (High school or junior college ß = .04, Bachelor degree or above ß = .09), feel anxious (mild, moderate ß = .02), feel pressured (moderate, severe ß = .08), have higher scores of the Short-Form Health Literacy Instrument (HLS-SF12) (ß = .31), The Self-Management Scale (SHMS) (ß = .16), EuroQol Five Dimensions Questionnaire (EQ-5D) (ß = .04) and EuroQol Visual Analogue Scale (EQ-VAS) (ß = .24), are more positive to donate. CONCLUSIONS: This study firstly discusses the public acceptance of organ donation through a nationwide sample around China. In this study, we discovered that Chinese residents' acceptance level of organ donation and that gender, house, anxiety, pressure, social support and health literacy were the main influencing factors on residents' attitudes. RELEVANCE TO CLINICAL PRACTICE: To figure out the Chinese public acceptance and its influencing factors of organ donation can help nurse transplant coordinators to recognise the target population and the obstacles of organ donation. PATIENT OR PUBLIC CONTRIBUTION: At the phase of collecting data, participants were recruited to fill the questionnaires.
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Transplante de Órgãos , Obtenção de Tecidos e Órgãos , Masculino , Criança , Humanos , Estudos Transversais , Conhecimentos, Atitudes e Prática em Saúde , Inquéritos e Questionários , ChinaRESUMO
Sucrose synthase (SUS) is a common sugar-base transfer enzyme in plants, and sucrose phosphate synthase (SPS) is one of the major enzymes in higher plants that regulates sucrose synthesis. However, information of the SPS and SUS gene families in Actinidia, as well as their evolutionary and functional properties, is limited. According to the SPS and SUS proteins conserved domain of Arabidopsis thaliana, we found 6 SPS genes and 6 SUS genes from A. chinensis (cultivar: 'Hongyang'), and 3 SPS genes and 6 SUS genes from A. eriantha (cultivar: 'White'). The novel CDC50 conserved domains were discovered on AcSUS2, and all members of the gene family contain similar distinctive conserved domains. The majority of SUS and SPS proteins were hydrophilic, lipid-soluble enzymes that were expected to be found in the cytoplasm. The tertiary structure of SPS and SUS protein indicated that there were many tertiary structures in SPS, and there were windmill-type and spider-type tertiary structures in SUS. The phylogenetic tree was created using the neighbor-joining method, and members of the SPS and SUS gene families are grouped into three subgroups. Genes with comparable intron counts, conserved motifs, and phosphorylation sites were clustered together first. SPS and SUS were formed through replication among their own family members. AcSPS1, AcSPS2, AcSPS4, AcSPS5, AcSUS5, AcSUS6, AeSPS3, AeSUS3 and AeSUS4 were the important genes in regulating the synthesis and accumulation of sucrose for Actinidia during the fruit growth stages.
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Actinidia , Arabidopsis , Actinidia/genética , Actinidia/metabolismo , Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas , Glucosiltransferases/genética , Glucosiltransferases/metabolismo , Filogenia , Sacarose/metabolismoRESUMO
ABSTRACT: Angioplasty often fails due to the abnormal proliferation of vascular smooth muscle cells (VSMCs). Success rates of angioplasty may increase following the administration of an agent that effectively ameliorates aberrant vascular remodeling. Icariside II (ICS-II) is a natural flavonol glycoside extract from the Chinese herbal medicine Epimedii that possesses several medicinal qualities that are beneficial in humans. Nevertheless, the role of ICS-II in addressing aberrant vascular remodeling have yet to be clarified. The current investigation studies the molecular effects of ICS-â ¡ on balloon-inflicted neointimal hyperplasia in rats in vivo and on platelet-derived growth factor-induced vascular proliferation in primary rat aortic smooth muscle cells (VSMCs) in vitro. ICS-II was found to be as effective as rapamycin, the positive control used in this study. ICS-II inhibited neointimal formation in injured rat carotid arteries and notably reduced the expression of Wnt7b. ICS-â ¡ significantly counteracted platelet-derived growth factor-induced VSMCs proliferation. Cell cycle analysis showed that ICS-II triggered cell cycle arrest during the G1/S transition. Western blot analysis further indicated that this cell cycle arrest was likely through Wnt7b suppression that led to CCND1 inhibition. In conclusion, our findings demonstrate that ICS-II possesses significant antiproliferative qualities that counteracts aberrant vascular neointimal hyperplasia. This phenomenon most likely occurs due to the suppression of the Wnt7b/CCND1 axis.
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Lesões das Artérias Carótidas , Remodelação Vascular , Animais , Lesões das Artérias Carótidas/tratamento farmacológico , Lesões das Artérias Carótidas/metabolismo , Movimento Celular , Proliferação de Células , Flavonoides , Hiperplasia/metabolismo , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , Neointima/metabolismo , Fator de Crescimento Derivado de Plaquetas/metabolismo , Fator de Crescimento Derivado de Plaquetas/farmacologia , Ratos , Ratos Sprague-DawleyRESUMO
INTRODUCTION: Mulberry (Morus alba L.) leaves are widely used in traditional Chinese medicine for their antioxidant, anti-inflammatory, antibacterial, anti-obesity, antidiabetic, antiatherosclerotic, and anticancer properties. The current study aimed to investigate the effect of mulberry leaf extract (MLE) on Staphylococcus aureus (S. aureus)-induced conjunctivitis (5 × 109 colony-forming units, 0.5 mL/eye) in a rabbit model. METHODS: Rabbits were treated with MLE (5 mL/kg·d-1 and 10 mL/kg·d-1), 0.9% saline, pearl bright eye (PBE) drops, or erythromycin eye ointment (EEO) group for 5 days. The ocular infection symptoms, bacterial negative conversion rate, and conjunctival histopathological changes of rabbits in each group were observed. The expression of caspase-1, apoptosis-associated speck-like protein containing a caspase recruitment domain, NOD-like receptor leucine-rich pyrin domain-containing protein 3 (NLRP3), interleukin (IL)-18, IL-6, IL-1ß, TNFα, Keap1, and nuclear factor erythroid 2-related factor 2 (Nrf2) in conjunctival tissue of rabbits were detected by quantitative real-time reverse transcription PCR and/or Western blot analysis. RESULTS: The results showed that MLE treatment significantly reduced the clinical sign scores of conjunctivitis, alleviated clinical signs, and decreased bacterial load, and histological damage in a time- and dose-dependent manner was compared to that in the control group. The antibacterial and anti-inflammatory activities of MLE (10 mL/kg·d-1) were similar to those of the positive control drug PBE and EEO. In addition, MLE significantly decreased the levels of pro-inflammatory cytokines, downregulated the NLRP3 inflammasome, and upregulated the Nrf2 system. CONCLUSIONS: MLE is effective in alleviating S. aureus-induced conjunctivitis in rabbits, and this mechanism is associated with the inhibition of the NLRP3 inflammasome and activation of the Nrf2 system to regulate pro-inflammatory signaling.
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Conjuntivite , Morus , Infecções Estafilocócicas , Animais , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Conjuntivite/tratamento farmacológico , Citocinas/metabolismo , Regulação para Baixo , Inflamassomos , Interleucina-1beta/metabolismo , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Coelhos , Infecções Estafilocócicas/tratamento farmacológico , Staphylococcus aureus/metabolismo , Regulação para CimaRESUMO
In times of public health emergencies, health agencies need to engage and communicate with the public in real-time to share updates and accurate information. This is especially the case for the COVID-19 pandemic where public engagement can potentially save lives and flatten the curve. This paper considers how the use of interactive features and strategic network positions of health agencies on social media influenced their public engagement outcomes. Specifically, we analyzed 203 U.S. public health agencies' Twitter activity and the public engagement they received by extracting data from a large-scale Twitter dataset collected from January 21st to May 31st, 2020. Results show that health agencies' network position in addition to their two-way communication strategy greatly influenced the level of public engagement with their COVID-19 related content on Twitter. Findings highlight the benefits of strategic social media communication of public health agencies resides not only in how agencies use social media but also in their formation of network position to amplify their visibility. As official sources of health and risk information, public health agencies should coordinate their social media communication efforts to strategically position themselves in advantageous network positions to augment public engagement outcomes.
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COVID-19 , Mídias Sociais , COVID-19/epidemiologia , Comunicação , Humanos , Pandemias , Saúde PúblicaRESUMO
We present a compact, monolithic optical reference for the frequency stabilized laser of future inter-satellite laser interferometer missions. A prototype based on the integration of a high-finesse cavity and associate optics has been designed to be space compatible while maintaining sufficient stability. The prototype has then been developed with a space-qualified bonding technique, and an in situ multi-degree-of-freedom alignment method. The performances of the optical reference have been studied by beat note analysis with another frequency stabilized laser, and the preliminary results are in agreement with the potential requirements of future space missions.
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OBJECTIVE: Melanoma accounts for 80% of skin cancer deaths. The pathogenesis of melanoma is regulated by gene networks. Thus, we aimed here to identify gene networks and hub genes associated with melanoma and to further identify their underlying mechanisms. METHODS: GTEx (normal skin) and TCGA (melanoma tumor) RNA-seq datasets were employed for this purpose. We conducted weighted gene co-expression network analysis (WGCNA) to identify key modules and hub genes associated with melanoma. Log-rank analysis and multivariate Cox model analysis were performed to identify prognosis genes, which were validated using two independent melanoma datasets. We also evaluated the correlation between prognostic gene and immune cell infiltration. RESULTS: The blue module was the most relevant for melanoma and was thus considered the key module. Intersecting genes were identified between this module and differentially expressed genes (DEGs). Finally, 72 genes were identified and verified as hub genes using the Oncomine database. Log-rank analysis and multivariate Cox model analysis identified 13 genes that were associated with the prognosis of the metastatic melanoma group, and RTP4 was validated as a prognostic gene using two independent melanoma datasets. RTP4 was not previously associated with melanoma. When we evaluated the correlation between prognostic gene and immune cell infiltration, we discovered that RTP4 was associated with immune cell infiltration. Further, RTP4 was significantly associated with genes encoding components of immune checkpoints (PDCD1, TIM-3, and LAG3). CONCLUSIONS: RTP4 is a novel prognosis-related hub gene in cutaneous melanoma. The novel gene RTP4 identified here will facilitate the exploration of the molecular mechanism of the pathogenesis and progression of melanoma and the discovery of potential new target for drug therapy.
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Redes Reguladoras de Genes , Melanoma/genética , Neoplasias Cutâneas/genética , Humanos , Prognóstico , Mapas de Interação de Proteínas , Melanoma Maligno CutâneoRESUMO
Ascorbate peroxidase (APX) is one of the important antioxidant enzymes in the active oxygen metabolism pathway of plants and animals, especially it is the key enzyme to clear H2O2 in chloroplast and the main enzyme of vitamin C metabolism. However, knowledge about APX gene family members and their evolutionary and functional characteristics in kiwifruit is limited. In this study, we identified 13 members of the APX gene family in the kiwifruit (cultivar: Hongyang) genome according the APX proteins conserved domain of Arabidopsis thaliana. Phylogenetic analysis by maximum likelihood split these 13 genes into four groups. The APX gene family members were distributed on nine chromosomes (Nos. 4, 5, 11, 13, 20, 21, 23, 25, 28). Most of the encoded hydrophilic and lipid-soluble enzymes were predicted to be located in the cytoplasm, nucleus and chloroplast. Among them, AcAPX4, AcAPX5, AcAPX8, AcAPX12 were transmembrane proteins, and AcAPX8 and AcAPX12 had the same transmembrane domain. The gene structure analysis showed that AcAPXs were composed of 4-22 introns, except that AcAPX10 was intron-free. Multiple expectation maximization for motif elicitation program (MEME) analyzed 13 APX protein sequences of Actinidia chinensis and identified 10 conserved motifs ranging in length from 15 to 50 amino acid residues. Additionally, the predicted secondary structures of the main motifs consisted of α-helix and random coils. The gene expression of fruits in different growth stages and bagging treatment were determined by qRT-PCR. The results showed that 8 AcAPXs had the highest expression levels during the color turning period and only the gene expression of AcAPX3 was consistent with the ascorbic acid content; five AcAPXs were consistent with the ascorbic acid content after bagging. Our data provided evolutionary and functional information of AcAPX gene family members and revealed the gene expression of different members in different growth stages and bagging treatments These results may be useful for future studies of the structures and functions of AcAPX family members.
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Actinidia , Ascorbato Peroxidases , Actinidia/genética , Ascorbato Peroxidases/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Peróxido de Hidrogênio , Filogenia , Proteínas de PlantasRESUMO
Pollen grains are covered by exine that protects the pollen from stress and facilitates pollination. Here we isolated a male sterile mutant s13283 in rice exhibiting aborted pollen with abnormal exine and defective aperture. The mutant gene encodes a novel plasma membrane-localized legume-lectin receptor kinase that we named OsLecRK-S.7. OsLecRK-S.7 was expressed at different levels in all tested tissues and throughout anther development. In vitro kinase assay showed OsLecRK-S.7 capable of autophosporylation. Mutation in s13283 (E560K) and mutation of the conserved ATP binding site (K418E) both knocked out the kinase activity. Mass spectrometry showed Thr376 , Ser378 , Thr386 , Thr403 , and Thr657 to be the autophosphorylation sites. Mutation of individual autophosphorylation site affected the in vitro kinase activity to different degrees, but did not abolish the gene function in fertility complementation. oslecrk-s.7 mutant plant overexpressing OsLecRK-S.7 recovered male fertility but showed severe growth retardation with reduced number of tillers, and these phenotypes were abolished by E560K or K418E mutation. The results indicated that OsLecRK-S.7 was a key regulator of pollen development.
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Lectinas/metabolismo , Oryza/enzimologia , Oryza/fisiologia , Pólen/enzimologia , Pólen/crescimento & desenvolvimento , Proteínas Quinases/metabolismo , Membrana Celular/enzimologia , Fertilidade , Regulação da Expressão Gênica de Plantas , Mutação/genética , Oryza/genética , Oryza/ultraestrutura , Fenótipo , Filogenia , Pólen/genética , Pólen/ultraestrutura , Proteínas Quinases/genéticaRESUMO
Pollen exine contains complex biopolymers of aliphatic lipids and phenolics. Abnormal development of pollen exine often leads to plant sterility. Molecular mechanisms regulating exine formation have been studied extensively but remain ambiguous. Here we report the analyses of three GDSL esterase/lipase protein genes, OsGELP34, OsGELP110, and OsGELP115, for rice exine formation. OsGELP34 was identified by cloning of a male sterile mutant gene. OsGELP34 encodes an endoplasmic reticulum protein and was mainly expressed in anthers during pollen exine formation. osgelp34 mutant displayed abnormal exine and altered expression of a number of key genes required for pollen development. OsGELP110 was previously identified as a gene differentially expressed in meiotic anthers. OsGELP110 was most homologous to OsGELP115, and the two genes showed similar gene expression patterns. Both OsGELP110 and OsGELP115 proteins were localized in peroxisomes. Individual knockout of OsGELP110 and OsGELP115 did not affect the plant fertility, but double knockout of both genes altered the exine structure and rendered the plant male sterile. OsGELP34 is distant from OsGELP110 and OsGELP115 in sequence, and osgelp34 and osgelp110/osgelp115 mutants were different in anther morphology despite both were male sterile. These results suggested that OsGELP34 and OsGELP110/OsGELP115 catalyze different compounds for pollen exine development.
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Esterases/metabolismo , Oryza/enzimologia , Oryza/crescimento & desenvolvimento , Proteínas de Plantas/metabolismo , Pólen/enzimologia , Pólen/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas , Oryza/metabolismo , Peroxissomos/metabolismo , Pólen/metabolismoRESUMO
BACKGROUND: Crocin (CRO), chlorogenic acid (CGA), geniposide (GEN), and quercetin (QUE) are all natural compounds with anti-obesity properties, in particular, hypolipidemic effects, which have been widely used for the treatment of obesity-related metabolic diseases. However, it is not yet known whether these compounds interact synergistically. Here, we investigated the effects and molecular mechanisms of CRO, CGA, GEN, QUE, and a combination of all four compounds (CCGQ), on lipid accumulation in human hepatoma (HepG2 cells). METHODS: The optimal concentration of CRO, CGA, GEN, QUE to stimulate HepG2 cells proliferation was determined using MTT assay. HepG2 cells were pretreated with 10 µmol/L simvastatin, 1 µmol/L CRO, 30 µmol/L CGA, 10 µmol/L GEN, 10 µmol/L QUE, and CCGQ (a combination of 1 µmol/L CRO, 30 µmol/L CGA, 10 µmol/L GEN, and 10 µmol/L QUE) for 24 or 48 h. Oil red O staining and extracellular TC and TG levels were detected. The RT-PCR was used to observe on cholesterol metabolism-related gene expression. Immunocytochemistry and western-blot assayed the 3-hydroxy-3-methylglutaryl-coenzyme (HMGCR) protein expression in HepG2 cells. RESULTS: Compared to those of control, we demonstrated that treating HepG2 cells for 48 h with CCGQ resulted in a strong synergistic effect, causing a marked decrease in lipid deposition in comparison to individual treatments, in both triglyceride and total cholesterol (CRO, 5.74- and 1.49-folds; CGA, 3.38- and 1.12-folds; GEN, 4.04- and 1.44-folds; QUE, 3.36- and 1.24-folds; simvastatin, 5.49- and 1.83-folds; and CCGQ, 7.75- and 2.20-folds), and Oil red O staining assays. In addition, CCGQ treatment increased ATP-binding cassette transporter (ABCA1), cholesterol 7α-hydroxylase (CYP7A1), and AMP-activated protein kinase 2α (AMPKα2) mRNA expression, while decreasing sterol regulatory element binding protein 2 (SREBP2), and liver X receptor alpha (LXRα) mRNA expression. Notably, CCGQ was more effective in decreasing HMGCR expression than the individual treatments. CONCLUSION: The CCGQ combination has potential, both as a complementary therapy for hyperlipemia, and in preventing further obesity-related complications.
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Carotenoides/farmacologia , Ácido Clorogênico/farmacologia , Colesterol/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Compostos Fitoquímicos/farmacologia , Sinergismo Farmacológico , Células Hep G2 , Humanos , Iridoides/farmacologia , Quercetina/farmacologiaRESUMO
We investigated the effect of external and internal osmotic stress on the profile of long-chain polyunsaturated fatty acids (LC-PUFA) in euryhaline eels Anguilla japonica. Freshwater (FW) fish were transferred to seawater (SW) for external osmotic stress or subjected to internal stress through injection with hypertonic saline. FW eels injected with isotonic saline served as controls. Plasma osmolality, Na+ concentration, and gill Na+/K+ -ATPase activity increased, but hematocrit decreased compared with controls in eels exposed to external or internal osmotic stress. The expression of two major transporter genes for SW adaptation, the Na+ -K+ -2Cl - co-transporter 1a (NKCC1a) in the gill and NKCC2b in the intestine, was up-regulated only in SW-transferred eels, suggesting a direct impact of SW on the gill and intestine via SW ingestion. Total LC-PUFA contents and DHA (22:6 n-3) increased in the gill and liver of SW-transferred eels and in the intestine of hypertonic saline-injected eels. However, total LC-PUFA content in plasma decreased after both external and internal osmotic stimuli. In contrast, the gene expression of two key enzymes involved in the LC-PUFA biosynthesis, Δ6 fatty acid desaturase and elongase, did not change in the gill, intestine and liver of osmotically stressed eels. These results indicate that LC-PUFA is possibly involved in osmoregulation and the increased LC-PUFA contents of osmoregulatory organs might be a result of LC-PUFA transport via circulation, rather than through de novo biosynthesis.
Assuntos
Anguilla/sangue , Ácidos Graxos Insaturados/sangue , Pressão Osmótica , Adaptação Fisiológica/fisiologia , Anguilla/metabolismo , Animais , Ácidos Graxos Insaturados/metabolismo , Proteínas de Peixes/metabolismo , Água Doce , Brânquias/enzimologia , Intestinos/enzimologia , Água do Mar , Equilíbrio HidroeletrolíticoRESUMO
CONTEXT: Eucommia ulmoides Oliver (Eucommiaceae) leaf exhibits beneficial lipid-lowering and anti-obesity effects. However, the mechanisms remain unknown. OBJECTIVE: The objective of this study is to investigate the lipid-lowering effects of chlorogenic acid (CGA)-enriched extract from this plant (CAEF) in human hepatoma HepG2 cells, focusing on cholesterol metabolism. MATERIALS AND METHODS: HepG2 cells were treated with CAEF (10, 20, 25, 40, 60, and 80 mg/L), CGA (0.3, 3, 30, 300, and 600 µmol/L), and simvastatin (0.1, 1, 10, 50, and 100 µmol/L) for 24 or 48 h. The cytotoxicity, Oil red O staining, total cholesterol, and triacylglycerol in supernatants were determined. The mRNA expression of genes involved in cholesterol metabolism was determined with RT-PCR. The protein expression of HMG-CoA reductase (HMGCR) was examined by immunocytochemistry and western-blot. RESULTS: The IC50 values were 59.2 mg/L for CAEF, 335.9 µmol/L for CGA, and 10.5 µmol/L for simvastatin. By treating cells with CAEF (25 mg/L), CGA (30 µmol/L), or simvastatin (10 µmol/L) for 48 h, the efflux of total cholesterol and triacylglycerol was increased (CAEF, 4.06- and 31.00-folds; CGA, 2.94- and 2.17-folds; and simvastatin, 3.94- and 24.67-folds), and the cellular lipid droplets were reduced in Oil red O staining. CAEF and CGA increased mRNA expression of ABCA1, CYP7A1, and AMPKα2, while CAEF and simvastatin decreased SREBP2. However, their effects on LXRα mRNA expression were variable. Importantly, all drugs significantly inhibited protein expression of HMGCR at mRNA and protein levels. DISCUSSION AND CONCLUSION: CAEF is a promising dietary supplement to prevent obesity and dyslipidemia and the effects appear to be due, at least in part, to regulating cholesterol metabolism through inhibition of HMGCR in HepG2 cells.
Assuntos
Ácido Clorogênico/química , Colesterol/metabolismo , Medicamentos de Ervas Chinesas/farmacologia , Eucommiaceae/química , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado/metabolismo , Relação Dose-Resposta a Droga , Medicamentos de Ervas Chinesas/isolamento & purificação , Expressão Gênica/efeitos dos fármacos , Células Hep G2 , Humanos , Metabolismo dos Lipídeos/genética , Fígado/efeitos dos fármacos , Folhas de Planta/químicaRESUMO
Native fat globules composed mainly of triglycerides are secreted as droplets of variable size. The size of fat globules affects the form of fat in dairy products and final functionality, which depends mainly on the composition of the globules and membrane. However, the relation between the composition and size of fat globules has not been studied in detail. In this study, differences in the lipid content and fatty acid composition related to the size of native fat globules were investigated using confocal Raman spectroscopy, which offers the possibility of acquisition and analysis of the Raman signal without disruption of a single fat globule in natural suspension. The results showed small fat globules (SFG) had a higher ratio of band intensities at 2885/2850 cm⻹, indicating SFG tend to have a triglyceride core in a fluid state with a milk fat globule membrane in a crystalline state. In addition, the SFG had a higher level of unsaturation compared to large fat globules, shown by a lower ratio at 1655/1443 cm⻹. Using cream with selected SFG would allow a harder and more costly churning process but lead to a softer butter.
Assuntos
Glicolipídeos/química , Glicoproteínas/química , Lipídeos/química , Leite/química , Análise Espectral Raman , Animais , Ácidos Graxos/química , Gotículas Lipídicas , Microscopia Confocal , Triglicerídeos/químicaRESUMO
To effectively control a robot's motion, it is common to employ a simplified model that approximates the robot's dynamics. Nevertheless, discrepancies between the actual mechanical properties of the robot and the simplified model can result in motion failures. To address this issue, this study introduces a pneumatic-driven bipedal musculoskeletal robot designed to closely match the mechanical characteristics of a simplified spring-loaded inverted pendulum (SLIP) model. The SLIP model is widely utilized in robotics due to its passive stability and dynamic properties resembling human walking patterns. A musculoskeletal bipedal robot was designed and manufactured to concentrate its center of mass within a compact body around the hip joint, featuring low leg inertia in accordance with SLIP model principles. Furthermore, we validated that the robot exhibits similar dynamic characteristics to the SLIP model through a sequential jumping experiment and by comparing its performance to SLIP model simulation.