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1.
Aging (Albany NY) ; 11(19): 8542-8555, 2019 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-31590160

RESUMO

Oxidative stress plays a vital role in the initiation and progression of age-related neurodegenerative diseases. Ameliorating oxidative damage is therefore considered as a beneficial strategy for the treatment of age-related neurodegenerative disorders. Probucol (Prob), a lipid-lowering prototype agent, was reported to treat cardiovascular diseases, chronic kidney disease and diabetes mellitus. However, whether Prob has an effect on age-related neurodegenerative diseases remains unknown. In the study, it was found that Prob ameliorated D-galactose (D-gal) induced cognitive deficits and neuronal loss in the hippocampal CA1 region. Moreover, Prob alleviated ROS and MDA levels by elevating SOD, GSH-PX and HO-1 mRNA and protein expressions, and improving plasmic and cerebral SOD and GSH-PX activities in D-gal treated mice. Furthermore, Prob promoted the dissociation of Keap1/Nrf2 complex leading to the accumulation of Nrf2 in nucleus, implying that the improved anti-oxidant property of Prob is mediated by Keap1/Nrf2 pathway. The study firstly demonstrates the favorable effects of Prob against cognitive impairments in a senescent mouse model, rendering this compound a promising agent for the treatment or prevention of age-related neurodegenerative disease.

2.
Gastroenterol Rep (Oxf) ; 7(3): 193-198, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31217983

RESUMO

Background: In addition to the stepwise manner of lymph-node metastasis from the primary tumour, the skip lymph-node metastasis (SLNM) was identified as a low-incidence metastasis of gastric cancer (GC). So far, both the mechanism and outcome of SLNM have not been elucidated completely. The purpose of this study was to analyse the clinical significance and the potential mechanism of SLNM in GC patients who had lymph-node metastasis. Methods: Clinicopathological data and follow-up information of 505 GC patients who had lymph-node metastasis were analysed to demonstrate the significance of SLNM in evaluating the prognostic outcome. According to the pathological results, all GC patients who had lymph-node metastasis were categorized into three groups: patients with the perigastric lymph-node metastasis, patients with the perigastric and extragastric lymph-node metastasis and patients with SLNM.Results: Among the 505 GC patients who had lymph-node metastasis, 24 (4.8%) had pathologically identified SLNM. The location of lymph-node metastasis was not significantly associated with 5-year survival rate and overall survival (OS) (P = 0.194). The stratified survival analysis results showed that the status of SLNM was significantly associated with the OS in patients with pN1 GC (P = 0.001). The median OS was significantly shorter in 19 pN1 GC patients with SLNM than in 100 patients with perigastric lymph-node metastasis (P < 0.001). The case-control matched logistic regression analysis results showed that tumour size (P = 0.002) was the only clinicopathological factor that may predict SLNM in pN1 GC patients undergoing curative surgery. Among the 19 pN1 GC patients with SLNM, 17 (89.5%) had metastatic lymph nodes along the common hepatic artery, around the celiac artery or in the hepatoduodenal ligament. Conclusions: SLNM may be considered a potentially practicable indicator for prognosis among various subgroups of pN1 GC patients.

3.
J Orthop Surg Res ; 14(1): 147, 2019 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-31118052

RESUMO

OBJECTIVES: This study aims to explore the clinical efficacy of applying a new reduction brace in the closed reduction of femoral shaft fracture. METHODS: A total of 18 patients with femoral shaft fracture, who were admitted to the Bone Trauma Surgery, Second Hospital of Shanxi Medical University, from September 2015 to January 2017, were chosen. A novel reduction brace combined with closed reduction intramedullary nail insertion on the traction table adopted for the orthopedic surgery was taken for the fixation. Then, surgical time, bleeding amount, and postoperational fracture healing time were recorded. RESULTS: All 18 patients with femoral shaft fracture successfully received closed reduction femoral nail with the application of the novel reduction brace. The follow-up period was 3-18 months, with an average of 12 months, and the femoral shaft fracture was well healed with good recovery of function. CONCLUSIONS: The design of the closed reduction brace of the femoral shaft fracture was reasonable, simple, and convenient to use and has a short learning curve. Furthermore, it led to little trauma to these patients and fully played the advantages of minimally invasive therapy for femoral fractures.


Assuntos
Fraturas do Fêmur/diagnóstico por imagem , Fraturas do Fêmur/cirurgia , Fixação de Fratura/instrumentação , Fixação de Fratura/métodos , Posicionamento do Paciente/instrumentação , Posicionamento do Paciente/métodos , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
4.
Oncol Rep ; 40(6): 3335-3345, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30272301

RESUMO

Leukocyte­derived microparticles (LMPs) include neutrophil­, lymphocyte­ and monocyte­derived MPs. LMPs act as proinflammatory mediators in autoimmune diseases, infectious diseases and vascular diseases. The present study examined the hypothesis that the percentage of LMPs was increased in patients with inflamed odontogenic keratocysts (OKCs), and investigated the biological effects of Jurkat cell­derived MPs on the fibroblasts of OKCs in vitro. Cyst fluid MPs, obtained by centrifugation of samples from 20 patients with inflamed OKCs, 3 patients with uninflamed OKCs, 15 patients with radicular cysts (RCs) and 12 patients with inflamed dentigerous cysts (DCs), were analyzed by transmission electron microscopy, dynamic light scattering and immunofluorescence staining. The percentages and concentrations of cyst fluid LMPs were further determined by flow cytometry. The cytokine levels of apoptotic Jurkat cell­derived MPs and Jurkat cell supernatants were compared by cytokine antibody arrays. Fibroblasts were isolated from 3 patients with OKC and co­cultured with apoptotic Jurkat cell­derived MPs with or without interleukin (IL)­15Rα to detect the levels of matrix metallopeptidase 9 (MMP­9) and receptor activator of nuclear factor­κB ligand (RANKL) by reverse transcription­quantitative polymerase chain reaction and enzyme­linked immunosorbent assay. The supernatant from Jurkat MPs­treated fibroblasts was collected to make conditioned medium in which the osteoclastogenesis of Raw264.7 cells was determined. Antibodies against human soluble (s)RANKL were added to the conditioned medium to investigate the inhibitory effects. Mean percentages of lymphocyte­ and neutrophil­derived MPs were significantly higher in inflamed OKCs than in DCs. Significant elevations in IL­15 were detected in apoptotic Jurkat cell­derived MPs compared with that in Jurkat cell supernatant. Furthermore, higher levels of MMP­9 and RANKL were detected in Jurkat cell MP­treated OKC fibroblasts, and this was partially blocked by IL­15Rα. Increased osteoclast­like cell formation was observed in the Jurkat MPs­treated fibroblast supernatant and Raw264.7 co­culture groups. The anti­human sRANKL antibody in the Jurkat MPs­treated fibroblast supernatant group decreased the osteoclastogenesis of the Raw264.7 cells. These results indicate that LMPs serve as novel communication tools that contribute toward the bone resorption of inflamed OKCs by inducing RANKL of OKC fibroblasts via IL­15.


Assuntos
Micropartículas Derivadas de Células/fisiologia , Interleucina-15/metabolismo , Linfócitos/citologia , Cistos Odontogênicos/imunologia , Ligante RANK/metabolismo , Adolescente , Adulto , Idoso , Animais , Micropartículas Derivadas de Células/metabolismo , Células Cultivadas , Criança , Técnicas de Cocultura , Feminino , Humanos , Células Jurkat , Linfócitos/metabolismo , Masculino , Camundongos , Pessoa de Meia-Idade , Células RAW 264.7 , Adulto Jovem
5.
Histopathology ; 73(6): 933-942, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29993138

RESUMO

AIMS: The purpose of this study was to explore the potential involvement of Fra-1, c-Jun and c-Fos, three vital members of the AP-1 complex, in the pathogenesis of odontogenic keratocysts (OKCs). METHODS AND RESULTS: Tissue samples, containing 10 normal oral mucosa (OM), 10 dentigerous cysts (DC) and 32 OKC specimens, were applied to investigate the expression levels of Fra-1, c-Jun and c-Fos by immunohistochemistry and real-time-quantitative polymerase chain reaction (RT-qPCR). The association between Fra-1, c-Jun and c-Fos expression levels and markers of proliferation [Ki-67, proliferating cell nuclear antigen (PCNA)], anti-apoptosis (Bcl-2) was then investigated in the OKC serial tissue sections. The results showed that Fra-1, c-Jun and c-Fos expression levels were increased significantly in OKCs compared to these in OM and DC tissue samples. Meanwhile, the expression levels of Fra-1, c-Jun and c-Fos were associated positively with the expression levels of Ki-67, PCNA and Bcl-2, as confirmed further by double-labelling immunofluorescence analysis and hierarchical analysis. CONCLUSIONS: This study revealed for the first time that Fra-1, c-Jun and c-Fos were overexpressed in OKCs and had a close correlation with proliferation and anti-apoptosis potential of OKCs.


Assuntos
Apoptose/fisiologia , Proliferação de Células/fisiologia , Mucosa Bucal/metabolismo , Cistos Odontogênicos/metabolismo , Proteínas Proto-Oncogênicas c-fos/metabolismo , Proteínas Proto-Oncogênicas c-jun/metabolismo , Humanos , Imuno-Histoquímica , Mucosa Bucal/patologia , Cistos Odontogênicos/patologia
6.
Int J Oncol ; 52(6): 1863-1874, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29620170

RESUMO

The aim of this study was to examine the level and basic characteristics of cell­derived microparticles (MPs) in the cyst fluids of odontogenic keratocysts (OKCs). For this purpose, MPs from the cyst fluids (CFMPs) of OKCs were purified by a classic differential centrifugation method and characterized by a transmission electron microscope and fluorescence microscope. Flow cytometric analysis was used to determine the size, concentration and cellular origins of the CFMPs. Moreover, the expression level of receptor activator for nuclear factor­κB ligand in the OKCs was evaluated by immunohistochemical staining and then analyzed for its correlation with the concentration of CFMPs by Spearman's rank correlation test. In addition, reverse transcription­quantitative polymerase chain reaction (RT­qPCR) and tartaric­resistant acid phosphatase (TRAP) staining were performed to examine the osteoclastogenesis of mouse bone marrow­derived macrophages (BMMs) in response to CFMPs. The results revealed that the levels of total CFMPs were significantly elevated in OKCs compared with dentigerous cysts (DCs) and radicular cysts (RCs). In addition, in vitro experiments further revealed that CFMPs derived from the OKCs of patients could be taken up by BMMs, leading to a significant increase in the mRNA expression levels of nuclear factor of activated T­cells 1 (NFATc1) and TRAP. Moreover, TRAP­positive multinucleated osteoclasts were successfully cultured in the presence of macrophage colony­stimulating factor (M­CSF) and CFMPs with BMMs. On the whole, our findings indicate that patients with OKCs have higher levels of CFMPs compared with patients with DCs and RCs, which may be associated with the bone resorption of OKCs.


Assuntos
Micropartículas Derivadas de Células/metabolismo , Cisto Dentígero/metabolismo , NF-kappa B/metabolismo , Fatores de Transcrição NFATC/genética , Fosfatase Ácida Resistente a Tartarato/genética , Adolescente , Adulto , Idoso , Animais , Micropartículas Derivadas de Células/genética , Células Cultivadas , Criança , Líquido Cístico/citologia , Cisto Dentígero/genética , Feminino , Humanos , Macrófagos/citologia , Masculino , Camundongos , Microscopia Eletrônica de Transmissão , Pessoa de Meia-Idade , Cistos Odontogênicos/genética , Cistos Odontogênicos/metabolismo , Adulto Jovem
7.
Sci Rep ; 8(1): 4743, 2018 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-29549366

RESUMO

Visceral pleural invasion (VPI) in stageI lung adenocarcinoma is an independent negative prognostic factor. However, no studies proved any morphologic pattern could be referred to as a prognostic factor. Thus, we aim to investigate the potential prognostic impact of VPI by extracting high-dimensional radiomics features on thin-section computed tomography (CT). A total of 327 surgically resected pathological-N0M0 lung adenocarcinoma 3 cm or less in size were evaluated. Radiomics signature was generated by calculating the contribution weight of each feature and validated using repeated leaving-one-out ten-fold cross-validation approach. The accuracy of proposed radiomics signature for predicting VPI achieved 90.5% with ROC analysis (AUC, 0.938, sensitivity, 90.6%, specificity, 93.2%, PPV: 91.2, NPV: 92.8). The cut-off value allowed separation of patients in the validation data into high-risk and low-risk groups with an odds ratio 12.01. Radiomics signature showed a concordance index of 0.895 and AIC value of 88.9% with regression analysis. Among these radiomics features, percentile 10%, wavEnLL_S_2, S_0_1_SumAverage represented as independent factors for determining VPI. Results suggested that radiomics signature on CT exhibited as an independent prognostic factor in discriminating VPI in lung adenocarcinoma and could potentially help to discriminate the prognosis difference in stage I lung adenocarcinoma.


Assuntos
Adenocarcinoma de Pulmão/patologia , Neoplasias Pulmonares/patologia , Pleura/patologia , Neoplasias Pleurais/patologia , Tomografia Computadorizada por Raios X/métodos , Adenocarcinoma de Pulmão/diagnóstico por imagem , Adenocarcinoma de Pulmão/cirurgia , Feminino , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/cirurgia , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Estadiamento de Neoplasias , Pleura/diagnóstico por imagem , Pleura/cirurgia , Neoplasias Pleurais/diagnóstico por imagem , Neoplasias Pleurais/cirurgia , Prognóstico
8.
Sci China Life Sci ; 61(1): 88-99, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28547583

RESUMO

Phospholipase C (PLC) are important regulatory enzymes involved in several lipid and Ca2+-dependent signaling pathways. Previous studies have elucidated the versatile roles of PLC genes in growth, development and stress responses of many plants, however, the systematic analyses of PLC genes in the important fiber-producing plant, cotton, are still deficient. In this study, through genome-wide survey, we identified twelve phosphatidylinositol-specific PLC (PI-PLC) and nine non-specific PLC (NPC) genes in the allotetraploid upland cotton Gossypium hirsutum and nine PI-PLC and six NPC genes in two diploid cotton G. arboretum and G.raimondii, respectively. The PI-PLC and NPC genes of G. hirsutum showed close phylogenetic relationship with their homologous genes in the diploid cottons and Arabidopsis. Segmental and tandem duplication contributed greatly to the formation of the gene family. Expression profiling indicated that few of the PLC genes are constitutely expressed, whereas most of the PLC genes are preferentially expressed in specific tissues and abiotic stress conditions. Promoter analyses further implied that the expression of these PLC genes might be regulated by MYB transcription factors and different phytohormones. These results not only suggest an important role of phospholipase C members in cotton plant development and abiotic stress response but also provide good candidate targets for future molecular breeding of superior cotton cultivars.


Assuntos
Genoma de Planta , Gossypium/genética , Família Multigênica , Fosfolipases Tipo C/genética , Fosfolipases Tipo C/metabolismo , Mapeamento Cromossômico , Diploide , Evolução Molecular , Duplicação Gênica , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Poliploidia , Regiões Promotoras Genéticas , Elementos Reguladores de Transcrição , Estresse Fisiológico/genética
9.
Biomed Res Int ; 2017: 4624890, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28512636

RESUMO

The aim of this study is to clarify whether YAP/TAZ is involved in the pathogenesis and proliferative growth of keratocystic odontogenic tumor (KCOT). The expression levels of YAP/TAZ and downstream proteins and genes in normal oral mucosa (OM) and KCOT were determined and compared by immunohistochemistry and real-time quantitative PCR. The results showed that the expression of YAP/TAZ and downstream proteins (Cyr61, CTGF) was significantly upregulated in KCOT with upregulation of Ki-67 compared to OM. Importantly, the mRNA levels of transcription factors (TEAD1, TEAD4, and RUNX2) and cell cycle related genes (CDK2, PCNA), which interact with the transcriptional coactivators YAP/TAZ, are also upregulated in the KCOT. In addition, the results from Spearman rank correlation test revealed the close relationship between YAP/TAZ and Ki-67, which was further evidenced by double-labelling immunofluorescence that revealed a synchronous distribution for YAP/TAZ with Ki-67 in KCOT samples. All the data suggested YAP/TAZ might be involved in the proliferative behavior of KCOT.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proliferação de Células/fisiologia , Mucosa Bucal/metabolismo , Cistos Odontogênicos/metabolismo , Tumores Odontogênicos/metabolismo , Fosfoproteínas/metabolismo , Fatores de Transcrição/metabolismo , Imunofluorescência/métodos , Humanos , Imuno-Histoquímica/métodos , Cistos Odontogênicos/patologia , Regulação para Cima/fisiologia
10.
FEBS Open Bio ; 7(3): 358-366, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28286731

RESUMO

Pyruvate kinase (PK, EC 2.7.1.40) is an important glycolytic enzyme involved in multiple physiological and developmental processes. In this study, we demonstrated that cotton cytosolic pyruvate kinase 6 (GhPK6) was phosphorylated at serines 215 and 402. Phosphorylation of GhPK6 at serine 215 inhibited its enzyme activity, whereas phosphorylation at both serine sites could promote its degradation. The phosphorylation-mediated ubiquitination of GhPK6 was gradually attenuated during the cotton fiber elongation process, which sufficiently explained the increase in the protein/mRNA ratios. These results collectively provided experimental evidence that cotton fiber elongation might be regulated at the post-translational level.

11.
Acta Biochim Biophys Sin (Shanghai) ; 49(1): 33-43, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27864277

RESUMO

Phospholipase D (PLD) hydrolyzes phospholipids to generate a free polar head group (e.g., choline) and a second messenger phosphatidic acid and plays diverse roles in plant growth and development, including seed germination, leaf senescence, root hair growth, and hypocotyl elongation. However, the function of PLD in cotton remains largely unexplored. Here, the comprehensive molecular characterization of GhPLDα1 was explored with its role in upland cotton (Gossypium hirsutum) fiber development. The GhPLDα1 gene was cloned successfully, and a sequence alignment showed that GhPLDα1 contains one C2 domain and two HKD (HxKxxxxD) domains. Quantitative reverse transcriptase-polymerase chain reaction measured the expression of GhPLDα1 in various cotton tissues with the highest level in fibers at 20 days post anthesis (d.p.a.). Fluorescent microscopy and immunoblotting in tobacco epidermis showed the GhPLDα1 distribution in both cell membranes and the cytoplasm. An activity assay indicated changes in PLDα enzyme activity in developing fiber cells with a peak level at 20 d.p.a., coinciding with the onset of cellulose accumulation and the increased H2O2 content during fiber development. Furthermore, the inhibition of PLDα activity obviously decreased the cellulose and H2O2 contents of in vitro-cultured cotton fibers. These results provide important evidence explaining the relationship of GhPLDα1 with secondary cell wall thickening in cotton fibers in that GhPLDα1 may correlate with the increased H2O2 content at the onset of secondary cell wall thickening, ultimately promoting cellulose biosynthesis.


Assuntos
Parede Celular , Fibra de Algodão , Fosfolipase D/genética , Regulação da Expressão Gênica de Plantas , Humanos , Microscopia de Fluorescência
12.
Front Plant Sci ; 7: 1722, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27909445

RESUMO

Plant microRNAs (miRNAs) have been shown to play essential roles in the regulation of gene expression. In this study, small RNA deep sequencing was applied to explore novel miRNAs expressed in elongating cotton fibers. A total of 46 novel and 96 known miRNAs, primarily derived from the corresponding specific loci in genome of Gossypium arboreum, were identified. 64 miRNAs were shown to be differentially expressed during the fiber elongation process; 16 were predicted to be novel miRNAs while the remaining 48 belong to known miRNA families. Furthermore, RLM-5' RACE (RNA ligase-mediated rapid amplification of 5'-cDNA ends) experiments identified the targets of eight important miRNAs, and the expression levels of these target genes were confirmed to be negatively correlated with the expression patterns of their corresponding miRNAs. We propose a potential functional network mediated through these eight miRNAs to illustrate their important functions in fiber elongation. Our study provides novel insights into the dynamic profiles of these miRNAs and a basis for investigating the regulatory mechanisms involved in the elongation of cotton fibers.

13.
PLoS One ; 11(11): e0166341, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27829020

RESUMO

Malate dehydrogenases (MDHs) play crucial roles in the physiological processes of plant growth and development. In this study, 13 and 25 MDH genes were identified from Gossypium raimondii and Gossypium hirsutum, respectively. Using these and 13 previously reported Gossypium arboretum MDH genes, a comparative molecular analysis between identified MDH genes from G. raimondii, G. hirsutum, and G. arboretum was performed. Based on multiple sequence alignments, cotton MDHs were divided into five subgroups: mitochondrial MDH, peroxisomal MDH, plastidial MDH, chloroplastic MDH and cytoplasmic MDH. Almost all of the MDHs within the same subgroup shared similar gene structure, amino acid sequence, and conserved motifs in their functional domains. An analysis of chromosomal localization suggested that segmental duplication played a major role in the expansion of cotton MDH gene families. Additionally, a selective pressure analysis indicated that purifying selection acted as a vital force in the evolution of MDH gene families in cotton. Meanwhile, an expression analysis showed the distinct expression profiles of GhMDHs in different vegetative tissues and at different fiber developmental stages, suggesting the functional diversification of these genes in cotton growth and fiber development. Finally, a promoter analysis indicated redundant but typical cis-regulatory elements for the potential functions and stress activity of many MDH genes. This study provides fundamental information for a better understanding of cotton MDH gene families and aids in functional analyses of the MDH genes in cotton fiber development.


Assuntos
Gossypium/genética , Malato Desidrogenase/genética , Sequência de Bases , Mapeamento Cromossômico , Sequência Conservada/genética , Genes de Plantas/genética , Estudo de Associação Genômica Ampla , Gossypium/enzimologia , Filogenia , Reação em Cadeia da Polimerase em Tempo Real , Alinhamento de Sequência
14.
Proteome Sci ; 14(1): 13, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27610046

RESUMO

BACKGROUND: Plenty of proteomic studies were performed to characterize the allotetraploid upland cotton fiber elongation process, whereas little is known about the elongating diploid cotton fiber proteome. METHODS: In this study, we used a two-dimensional electrophoresis-based comparative proteomic approach to profile dynamic proteomes of diploid Asian cotton ovules with attached fibers in the early stages of fiber elongation process. One-way ANOVA and Student-Newman-Keuls test were used to find the differentially displayed protein (DDP) spots. RESULTS: A total of 55 protein spots were found having different abundance ranging from 1 to 9 days post-anthesis (DPA) in a two-day interval. These 55 DDP spots were all successfully identified using high-resolution mass spectrometric analyses. Gene ontology analyses revealed that proteoforms involved in energy/carbohydrate metabolism, redox homeostasis, and protein metabolism are the most abundant. In addition, orthologues of the 13 DDP spots were also found in differential proteome of allotetraploid elongating cotton fibers, suggesting their possible essential roles in fiber elongation process. CONCLUSIONS: Our results not only revealed the dynamic proteome change of diploid Asian cotton fiber and ovule during early stages of fiber elongation process but also provided valuable resource for future studies on the molecular mechanism how the polyploidization improves the trait of fiber length.

15.
PLoS One ; 11(9): e0162928, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27632161

RESUMO

GRIM-19 (Gene associated with Retinoid-Interferon-induced Mortality 19) is a subunit of mitochondrial respiratory complex I in mammalian systems, and it has been demonstrated to be a multifunctional protein involved in the cell cycle, cell motility and innate immunity. However, little is known about the molecular functions of its homologues in plants. Here, we characterised GhMCS1, an orthologue of human GRIM-19 from cotton (Gossypium hirsutum L.), and found that it was essential for maintaining complex integrity and mitochondrial function in cotton. GhMCS1 was detected in various cotton tissues, with high levels expressed in developing fibres and flowers and lower levels in leaves, roots and ovules. In fibres at different developmental stages, GhMCS1 expression peaked at 5-15 days post anthesis (dpa) and then decreased at 20 dpa and diminished at 25 dpa. By Western blot analysis, GhMCS1 was observed to be localised to the mitochondria of cotton leaves and to colocalise with complex I. In Arabidopsis, GhMCS1 overexpression enhanced the assembly of complex I and thus respiratory activity, whereas the GhMCS1 homologue (At1g04630) knockdown mutants showed significantly decreased respiratory activities. Furthermore, the mutants presented with some phenotypic changes, such as smaller whole-plant architecture, poorly developed seeds and fewer trichomes. More importantly, in the cotton fibres, both the GhMCS1 transcript and protein levels were correlated with respiratory activity and fibre developmental phase. Our results suggest that GhMCS1, a functional ortholog of the human GRIM-19, is an essential subunit of mitochondrial complex I and is involved in cotton fibre development. The present data may deepen our knowledge on the potential roles of mitochondria in fibre morphogenesis.


Assuntos
Fibra de Algodão , Complexo I de Transporte de Elétrons/metabolismo , Gossypium/metabolismo , Proteínas de Plantas/metabolismo , Sequência de Aminoácidos , Gossypium/crescimento & desenvolvimento , Humanos , Proteínas de Plantas/química , Plantas Geneticamente Modificadas , Homologia de Sequência de Aminoácidos
16.
J Acoust Soc Am ; 140(1): EL137, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27475203

RESUMO

Obtaining the horizontal variation of temperature and current fields of a water column usually requires travel-time measurements of acoustic signals traveling along different paths between several horizontally distributed transceivers. This study explores the possibility of using a pair of transceivers deployed in a highly-reverberant harbor environment to extract spatial information of the water. Multipath acoustic propagation of two main arrival groups, i.e., direct arrivals and arrivals reflecting off the harbor side, was observed in the pulse responses measured in the harbor environment during the flood tide. Compared with the direct point measurements of temperature and current, the path-averaged measurements show a similar temporal variation during the experiment, demonstrating the possibility of estimating the spatial variation of the currents and temperatures using the multipath acoustic propagation.

17.
Planta ; 244(4): 915-26, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27316434

RESUMO

MAIN CONCLUSION: Cotton cytosolic pyruvate kinase GhPK6 is preferentially expressed in the late stage of fiber elongation process, transgenic experiments indicated that its expression level was negatively correlated to cell expansion rate. Pyruvate kinase (PK) plays vital regulatory roles in rapid cell growth in mammals. However, the function of PK in plant cell growth remains unclear. In allotetraploid upland cotton (Gossypium hirsutum L.), a total of 33 PK genes are encoded by the genome. Analysis of the transcriptome data indicated that only two cytosolic PK genes, GhPK6 and its duplicated gene GhPK26, are preferentially expressed in elongating cotton fiber cells. RT-qPCR and western blot analyses revealed that the expression of GhPK6 was negatively correlated with fiber elongation rate, which well explains the observed sharp increase of cytosolic PK activity at the end of fast fiber elongation process. Furthermore, virus-induced gene silencing of GhPK6 in cotton plants resulted in increased fiber cell elongation and reduced reactive oxygen species (ROS) accumulation. On the contrary, Arabidopsis plants ectopically expressing GhPK6 exhibited ROS-mediated growth inhibition, whereas the addition of ROS scavenging reagents could partly rescue this inhibition. These data collectively suggested that GhPK6 might play an important role in regulating cotton fiber elongation in a ROS-dependent inhibition manner.


Assuntos
Fibra de Algodão , Citosol/enzimologia , Gossypium/enzimologia , Proteínas de Plantas/metabolismo , Piruvato Quinase/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Sequência de Bases , Western Blotting , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica no Desenvolvimento , Regulação Enzimológica da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Genoma de Planta/genética , Gossypium/genética , Gossypium/crescimento & desenvolvimento , Família Multigênica/genética , Proteínas de Plantas/genética , Piruvato Quinase/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Homologia de Sequência do Ácido Nucleico , Tetraploidia
18.
PLoS One ; 11(5): e0156281, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27213891

RESUMO

In this study, 40 phospholipase D (PLD) genes were identified from allotetraploid cotton Gossypium hirsutum, and 20 PLD genes were examined in diploid cotton Gossypium raimondii. Combining with 19 previously identified Gossypium arboreum PLD genes, a comparative analysis was performed among the PLD gene families among allotetraploid and two diploid cottons. Based on the orthologous relationships, we found that almost each G. hirsutum PLD had a corresponding homolog in the G. arboreum and G. raimondii genomes, except for GhPLDß3A, whose homolog GaPLDß3 may have been lost during the evolution of G. arboreum after the interspecific hybridization. Phylogenetic analysis showed that all of the cotton PLDs were unevenly classified into six numbered subgroups: α, ß/γ, δ, ε, ζ and φ. An N-terminal C2 domain was found in the α, ß/γ, δ and ε subgroups, while phox homology (PX) and pleckstrin homology (PH) domains were identified in the ζ subgroup. The subgroup φ possessed a single peptide instead of a functional domain. In each phylogenetic subgroup, the PLDs showed high conservation in gene structure and amino acid sequences in functional domains. The expansion of GhPLD and GrPLD gene families were mainly attributed to segmental duplication and partly attributed to tandem duplication. Furthermore, purifying selection played a critical role in the evolution of PLD genes in cotton. Quantitative RT-PCR documented that allotetraploid cotton PLD genes were broadly expressed and each had a unique spatial and developmental expression pattern, indicating their functional diversification in cotton growth and development. Further analysis of cis-regulatory elements elucidated transcriptional regulations and potential functions. Our comparative analysis provided valuable information for understanding the putative functions of the PLD genes in cotton fiber.


Assuntos
Diploide , Gossypium/genética , Fosfolipase D/genética , Poliploidia , Sequência de Aminoácidos , Hibridização Genômica Comparativa , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Genoma de Planta , Família Multigênica , Filogenia
19.
Mol Plant ; 9(5): 650-661, 2016 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-26961720

RESUMO

Abscisic acid (ABA) plays crucial roles in plant growth and development, as well as in response to various environmental stresses. To date, many regulatory genes involved in the ABA response network have been identified; however, their roles have remained to be fully elucidated. In this study, we identified AtYY1, an Arabidopsis homolog of the mammalian C2H2 zinc-finger transcription factor Yin Yang 1 (YY1), as a novel negative regulator of the ABA response. AtYY1 is a dual-function transcription factor with both repression and activation domains. The expression of AtYY1 was induced by ABA and stress conditions including high salt and dehydration. The yy1 mutant was more sensitive to ABA and NaCl than the wild-type, while overexpressing AtYY1 plants were less sensitive. AtYY1 loss also enhanced ABA-induced stomatal closing and drought resistance. Moreover, AtYY1 can bind the ABA REPRESSOR1 (ABR1) promoter and directly upregulate ABR1 expression, as well as negatively regulate ABA- and salt-responsive gene expression. Additional analysis indicated that ABA INSENSITIVE4 (ABI4) might positively regulate AtYY1 expression and that ABR1 can antagonize this regulation. Our findings provide direct evidence that AtYY1 is a novel negative regulator of the ABA response network and that the ABI4-AtYY1-ABR1 regulatory pathway may fine-tune ABA-responsive gene expression in Arabidopsis.


Assuntos
Ácido Abscísico/farmacologia , Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Reguladores de Crescimento de Planta/farmacologia , Fatores de Transcrição/metabolismo , Arabidopsis/efeitos dos fármacos , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Secas , Regulação da Expressão Gênica de Plantas , Plantas Geneticamente Modificadas/efeitos dos fármacos , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Cloreto de Sódio/farmacologia , Estresse Fisiológico , Fatores de Transcrição/genética , Fator de Transcrição YY1/genética , Fator de Transcrição YY1/metabolismo
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