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1.
Plant Physiol ; 191(1): 96-109, 2023 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-36282529

RESUMO

Degradation of starch accumulated in pollen provides energy and cellular materials for pollen germination and pollen tube elongation. Little is known about the function of cytosolic disproportionating enzyme2 (DPE2) in rice (Oryza sativa). Here, we obtained several DPE2 knockout mutant (dpe2) lines via genomic editing and found that the mutants grew and developed normally but with greatly reduced seed-setting rates. Reciprocal crosses between dpe2 and wild-type plants demonstrated that the mutant was male sterile. In vitro and in vivo examinations revealed that the pollen of the dpe2 mutant developed and matured normally but was defective in germination and elongation. DPE2 deficiency increased maltose content in pollen, whereas it reduced the levels of starch, glucose, fructose, and adenosine triphosphate (ATP). Exogenous supply of glucose or ATP to the germination medium partially rescued the pollen germination defects of dpe2. The expression of cytosolic phosphorylase2 (Pho2) increased significantly in dpe2 pollen. Knockout of Pho2 resulted in a semi-sterile phenotype. We failed to obtain homozygous dpe2 pho2 double mutant lines. Our results demonstrate that maltose catalyzed by DPE2 to glucose is the main energy source for pollen germination and pollen tube elongation, while Pho2 might partially compensate for deficiency of DPE2.


Assuntos
Arabidopsis , Oryza , Tubo Polínico/genética , Tubo Polínico/metabolismo , Oryza/genética , Oryza/metabolismo , Arabidopsis/genética , Maltose/metabolismo , Pólen/genética , Pólen/metabolismo , Glucose/metabolismo , Amido/metabolismo , Germinação/genética
2.
Acta Pharmacol Sin ; 45(1): 52-65, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37674043

RESUMO

Gut microbiota disturbance and systemic inflammation have been implicated in the degeneration of dopaminergic neurons in Parkinson's disease (PD). How the alteration of gut microbiota results in neuropathological events in PD remains elusive. In this study, we explored whether and how environmental insults caused early neuropathological events in the substantia nigra (SN) of a PD mouse model. Aged (12-month-old) mice were orally administered rotenone (6.25 mg·kg-1·d-1) 5 days per week for 2 months. We demonstrated that oral administration of rotenone to ageing mice was sufficient to establish a PD mouse model and that microglial activation and iron deposition selectively appeared in the SN of the mice prior to loss of motor coordination and dopaminergic neurons, and these events could be fully blocked by microglial elimination with a PLX5622-formulated diet. 16 S rDNA sequencing analysis showed that the gut microbiota in rotenone-treated mice was altered, and mice receiving faecal microbial transplantation (FMT) from ageing mice treated with rotenone for 2 months exhibited the same pathology in the SN. We demonstrated that C-X-C motif chemokine ligand-1 (CXCL1) was an essential molecule, as intravenous injection of CXCL1 mimicked almost all the pathology in serum and SN induced by oral rotenone and FMT. Using metabolomics and transcriptomics analyses, we identified the PPAR pathway as a key pathway involved in rotenone-induced neuronal damage. Inhibition of the PPARγ pathway was consistent in the above models, whereas its activation by linoleic acid (60 mg·kg-1·d-1, i.g. for 1 week) could block these pathological events in mice intravenously injected with CXCL1. Altogether, these results reveal that the altered gut microbiota resulted in neuroinflammation and iron deposition occurring early in the SN of ageing mice with oral administration of rotenone, much earlier than motor symptoms and dopaminergic neuron loss. We found that CXCL1 plays a crucial role in this process, possibly via PPARγ signalling inhibition. This study may pave the way for understanding the "brain-gut-microbiota" molecular regulatory networks in PD pathogenesis. The aged C57BL/6 male mice with rotenone intragastric administration showed altered gut microbiota, which caused systemic inflammation, PPARγ signalling inhibition and neuroinflammation, brain iron deposition and ferroptosis, and eventually dopaminergic neurodegeneration in PD.


Assuntos
Microbioma Gastrointestinal , Doença de Parkinson , Camundongos , Animais , Masculino , Rotenona/toxicidade , Doenças Neuroinflamatórias , PPAR gama , Camundongos Endogâmicos C57BL , Doença de Parkinson/patologia , Substância Negra/patologia , Neurônios Dopaminérgicos/patologia , Inflamação/patologia , Ferro , Modelos Animais de Doenças
3.
Acta Pharmacol Sin ; 45(2): 268-281, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37674042

RESUMO

Cell senescence has been implicated in the pathology of Parkinson's disease (PD). Both abnormal α-synuclein aggregation and iron deposition are suggested to be the triggers, facilitators, and aggravators during the development of PD. In this study, we investigated the involvement of α-synuclein and iron in the process of cell senescence in a mouse model of PD. In order to overexpress α-syn-A53T in the substantia nigra pars compacta (SNpc), human α-syn-A53T was microinjected into both sides of the SNpc in mice. We found that overexpression of α-syn-A53T for one week induced significant pro-inflammatory senescence-associated secretory phenotype (SASP), increased cell senescence-related proteins (ß-gal, p16, p21, H2A.X and γ-H2A.X), mitochondrial dysfunction accompanied by dysregulation of iron-related proteins (L-ferritin, H-ferritin, DMT1, IRP1 and IRP2) in the SNpc. In contrast, significant loss of nigral dopaminergic neurons and motor dysfunction were only observed after overexpression of α-syn-A53T for 4 weeks. In PC12 cells stably overexpressing α-syn-A53T, iron overload (ferric ammonium citrate, FAC, 100 µM) not only increased the level of reactive oxygen species (ROS), p16 and p21, but also exacerbated the processes of oxidative stress and cell senescence signalling induced by α-syn-A53T overexpression. Interestingly, reducing the iron level with deferoxamine (DFO) or knockdown of transferrin receptor 1 (TfR1) significantly improved both the phenotypes and dysregulated proteins of cell senescence induced by α-syn-A53T overexpression. All these evidence highlights the toxic interaction between iron and α-synuclein inducing cell senescence, which precedes nigral dopaminergic neuronal loss in PD. Further investigation on cell senescence may yield new therapeutic agents for the prevention or treatment of PD.


Assuntos
Doença de Parkinson , Ratos , Camundongos , Animais , Humanos , Doença de Parkinson/metabolismo , alfa-Sinucleína/metabolismo , Neurônios Dopaminérgicos/metabolismo , Ferro/metabolismo , Substância Negra/metabolismo , Substância Negra/patologia , Dopamina/metabolismo , Senescência Celular , Modelos Animais de Doenças
4.
Plant Cell Environ ; 46(6): 1946-1961, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36850039

RESUMO

Metallochaperones are a unique class of proteins that play crucial roles in metal homoeostasis and detoxification. However, few metallochaperones have been functionally characterised in rice. Heterologous expression of Heavy metal-associated Isoprenylated Plant Protein 9 (OsHIPP9), a metallochaperone, altered yeast tolerance to cadmium (Cd) and copper (Cu). We investigated the physiological role of OsHIPP9 in rice. OsHIPP9 was primarily expressed in the root exodermis and xylem region of enlarged vascular bundles (EVB) at nodes. KO of OsHIPP9 increased the Cd concentrations of the upper nodes and panicle, but decreased Cd in expanded leaves. KO of OsHIPP9 decreased Cu uptake and accumulation in rice. Constitutive OX of OsHIPP9 increased Cd and Cu accumulation in aboveground tissues and brown rice. OsHIPP9 showed binding capacity for Cd and Cu. We propose that OsHIPP9 has dual metallochaperone roles, chelating Cd in the xylem region of EVB for Cd retention in the nodes and chelating Cu in rice roots to aid Cu uptake.


Assuntos
Metais Pesados , Oryza , Poluentes do Solo , Cádmio/metabolismo , Cobre/metabolismo , Metalochaperonas/metabolismo , Oryza/metabolismo , Metais Pesados/metabolismo , Saccharomyces cerevisiae/metabolismo , Raízes de Plantas/metabolismo , Poluentes do Solo/metabolismo
5.
Theor Appl Genet ; 136(3): 47, 2023 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-36912930

RESUMO

KEY MESSAGE: Plastidial α-glucan phosphorylase is a key factor that cooperates with plastidial disproportionating enzyme to control short maltooligosaccharide mobilization during the initiation process of starch molecule synthesis in developing rice endosperm. Storage starch synthesis is essential for grain filling. However, little is known about how cereal endosperm controls starch synthesis initiation. One of core events for starch synthesis initiation is short maltooligosaccharide (MOS) mobilization consisting of long MOS primer production and excess MOS breakdown. By mutant analyses and biochemical investigations, we present here functional identifications of plastidial α-glucan phosphorylase (Pho1) and disproportionating enzyme (DPE1) during starch synthesis initiation in rice (Oryza sativa) endosperm. Pho1 deficiency impaired MOS mobilization, triggering short MOS accumulation and starch synthesis reduction during early seed development. The mutant seeds differed significantly in MOS level and starch content at 15 days after flowering and exhibited diverse endosperm phenotypes during mid-late seed development: ranging from pseudonormal to shrunken (Shr), severely or excessively Shr. The level of DPE1 was almost normal in the PN seeds but significantly reduced in the Shr seeds. Overexpression of DPE1 in pho1 resulted in plump seeds only. DPE1 deficiency had no obvious effects on MOS mobilization. Knockout of DPE1 in pho1 completely blocked MOS mobilization, resulting in severely and excessively Shr seeds only. These findings show that Pho1 cooperates with DPE1 to control short MOS mobilization during starch synthesis initiation in rice endosperm.


Assuntos
Endosperma , Oryza , Endosperma/genética , Endosperma/metabolismo , Oryza/metabolismo , Fosforilases/genética , Fosforilases/metabolismo , Amido/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regulação da Expressão Gênica de Plantas
6.
Plant Physiol ; 187(1): 396-408, 2021 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-34618140

RESUMO

The endoplasmic reticulum (ER) quality control system monitors protein homeostasis and relies on the activity of many molecular chaperones. Binding immunoglobulin protein (BiP) is a major ER luminal chaperone that is involved in most functions of the organelle. BiP activity is tightly regulated by nucleotide exchange factors (NEFs). However, information about NEFs in plants is limited. We obtained a Fes1-like protein (OsFes1C) through isobaric tags for relative and absolute quantitation-based proteomics analysis of ER-stressed rice (Oryza sativa) seeds. Unlike its homologs in yeast and mammals, which are located in the cytosol and respond to heat stress, OsFes1C is an ER membrane protein and responds to ER and salt stresses. OsFes1C interacts directly with OsBiP1 and the interaction is inhibited by ATP but promoted by ADP, suggesting that OsFes1C acts as a potential NEF of OsBiP1 in vivo. Overexpression or suppression of OsFes1C led to hypersensitivity to ER stress and affected the growth of rice. Furthermore, we established that OsFes1C directly interacts with a putative salt response protein and is involved in the salt response. Taken together, our study marks an important step toward elucidating the functional mechanisms of an identified ER stress response factor in rice.


Assuntos
Estresse do Retículo Endoplasmático/genética , Chaperonas Moleculares/genética , Oryza/fisiologia , Proteínas de Plantas/genética , Estresse Salino/genética , Chaperonas Moleculares/metabolismo , Oryza/genética , Proteínas de Plantas/metabolismo
7.
Cell Commun Signal ; 20(1): 152, 2022 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-36153596

RESUMO

BACKGROUND: Tumorigenic phenotype of M2 tumor-associated macrophages promote tumor progression in response to exosomes cues imposed by tumor cells. However, the effect and underlying mechanisms of clear cell renal cell carcinoma (ccRCC)-derived exosomes (ccRCC-exo) on instructing macrophages phenotype remains unclear. METHODS: Macrophages were cocultured with ccRCC-exo and then evaluate the polarization of macrophages and migration of ccRCC cells. The effect and mechanism of lncRNA AP000439.2 overexpressed or deleted exosomes on macrophages M2 polarization were examined. Xenograft tumor mice model was used for in vivo validation. RESULTS: The ccRCC-exo significantly activated macrophages to M2 phenotype presented by increased expression of transforming growth factor-beta (TGF-ß) and interleukin 10 (IL-10) at mRNA and protein levels, and these M2 macrophages in turn facilitating the migration of ccRCC cells. LncRNA AP000439.2 was highly enriched in the ccRCC-exo. Overexpression of exosomal AP000439.2 promoted M2 macrophage polarization whereas AP000439.2-deficient exosome had the opposite effects. Nuclear-localized AP000439.2 directly interacted with signal transducer and activator of transcription 3 (STAT3) proteins and phosphorylated STAT3 in macrophages. RNA-Seq results showed overexpression of AP000439.2 activated NF-κB signaling pathway. Silencing of STAT3 suppressed overexpression of AP000439.2-induced up-regulation of TGF-ß and IL-10 expression, and p65 phosphorylation. AP000439.2-deleted exosome inhibited tumor growth in vivo. CONCLUSION: Exosomes from ccRCC deliver AP000439.2 to promote M2 macrophage polarization via STAT3, thus enhancing ccRCC progression, indicating exosomal AP000439.2 might be a novel therapeutic target in ccRCC. Video Abstract.


Assuntos
Carcinoma de Células Renais , Exossomos , Neoplasias Renais , MicroRNAs , RNA Longo não Codificante , Animais , Carcinoma de Células Renais/patologia , Linhagem Celular Tumoral , Exossomos/metabolismo , Humanos , Interleucina-10/metabolismo , Neoplasias Renais/metabolismo , Ativação de Macrófagos/genética , Macrófagos/metabolismo , Camundongos , MicroRNAs/genética , NF-kappa B/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , RNA Mensageiro/metabolismo , Fator de Transcrição STAT3/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Fatores de Crescimento Transformadores/metabolismo
8.
Circ Res ; 127(4): 534-549, 2020 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-32316875

RESUMO

RATIONALE: SNX10 (sorting nexin 10) has been reported to play a critical role in regulating macrophage function and lipid metabolism. OBJECTIVE: To investigate the precise role of SNX10 in atherosclerotic diseases and the underlying mechanisms. METHODS AND RESULTS: SNX10 expression was compared between human healthy vessels and carotid atherosclerotic plaques. Myeloid cell-specific SNX10 knockdown mice were crossed onto the APOE-/- (apolipoprotein E) background and atherogenesis (high-cholesterol diet-induced) was monitored for 16 weeks. We found that SNX10 expression was increased in atherosclerotic lesions of aortic specimens from humans and APOE-/- mice. Myeloid cell-specific SNX10 deficiency (Δ knockout [KO]) attenuated atherosclerosis progression in APOE-/- mice. The population of anti-inflammatory monocytes/macrophages was increased in the peripheral blood and atherosclerotic lesions of ΔKO mice. In vitro experiments showed that SNX10 deficiency-inhibited foam cell formation through interrupting the internalization of CD36, which requires the interaction of SNX10 and Lyn-AKT (protein kinase B). The reduced Lyn-AKT activation by SNX10 deficiency promoted the nuclear translocation of TFEB (transcription factor EB), thereby enhanced lysosomal biogenesis and LAL (lysosomal acid lipase) activity, resulting in an increase of free fatty acids to fuel mitochondrial fatty acid oxidation. This further promoted the reprogramming of macrophages and shifted toward the anti-inflammatory phenotype. CONCLUSIONS: Our data demonstrate for the first time that SNX10 plays a crucial role in diet-induced atherogenesis via the previously unknown link between the Lyn-Akt-TFEB signaling pathway and macrophage reprogramming, suggest that SNX10 may be a potentially promising therapeutic target for atherosclerosis treatment.


Assuntos
Doenças da Aorta/metabolismo , Aterosclerose/metabolismo , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Reprogramação Celular/fisiologia , Macrófagos/fisiologia , Nexinas de Classificação/fisiologia , Animais , Apolipoproteínas E/genética , Aterosclerose/sangue , Aterosclerose/patologia , Antígenos CD36/metabolismo , Núcleo Celular/metabolismo , Progressão da Doença , Ácidos Graxos não Esterificados/metabolismo , Células Espumosas/citologia , Humanos , Lisossomos/fisiologia , Macrófagos/citologia , Camundongos , Mitocôndrias/metabolismo , Monócitos/citologia , Oxirredução , Proteínas Proto-Oncogênicas c-akt/metabolismo , Nexinas de Classificação/deficiência , Nexinas de Classificação/genética , Esterol Esterase/metabolismo
9.
New Phytol ; 225(5): 2094-2107, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31618451

RESUMO

Odd-numbered primary alcohols are components of plant cuticular wax, but their biosynthesis remains unknown. We isolated a rice wax crystal-sparse leaf 5 (WSL5) gene using a map-based cloning strategy. The function of WSL5 was illustrated by overexpression and knockout in rice, heterologous expression in Arabidopsis and transient expression in tobacco leaves. WSL5 is predicted to encode a cytochrome P450 family member CYP96B5. The wsl5 mutant lacked crystalloid platelets on the surface of cuticle membrane, and its cuticle membrane was thicker than that of the wild-type. The wsl5 mutant is more tolerant to drought stress. The load of C23 -C33 alkanes increased, whereas the C29 primary alcohol reduced significantly in wsl5 mutant and WSL5 knockout transgenic plants. Overexpression of WSL5 increased the C29 primary alcohol and decreased alkanes in rice leaves. Heterologous expression of WSL5 increased the C29 primary alcohol and decreased alkanes, secondary alcohol, and ketone in Arabidopsis stem wax. Transient expression of WSL5 in tobacco leaves also increased the production C29 primary alcohol. WSL5 catalyzes the terminal hydroxylation of alkanes, yielding odd-numbered primary alcohols, and is involved in the formation of epidermal wax crystals on rice leaf, affecting drought sensitivity.


Assuntos
Oryza , Álcoois , Alcanos , Sistema Enzimático do Citocromo P-450/genética , Família , Regulação da Expressão Gênica de Plantas , Oryza/genética , Oryza/metabolismo , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Ceras
10.
J Chem Phys ; 152(24): 244707, 2020 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-32610948

RESUMO

Engineering the interface and surface structures of semiconductor-based photoelectrodes for improved charge transfer dynamics and promoted water redox reaction kinetics is essential to achieve efficient photoelectrochemical (PEC) water splitting. In this work, α-Fe2O3 nanorods, successively coated with TiO2 and CoOx thin layers, were reported as the photoanode for solar-driven water oxidation. The obtained α-Fe2O3/TiO2/CoOx photoanode exhibits superior PEC performance as compared to bare α-Fe2O3, with a 3.3-time improvement in photocurrent density at 1.23 V vs reversible hydrogen electrode. This significant enhancement results from the formed heterojunction between α-Fe2O3 and TiO2 for the accelerated photogenerated charge separation and transfer as well as the passivated surface defects by the TiO2 overlayer for reduced charge recombination. Additionally, the existence of CoOx as the oxygen evolution catalyst significantly facilitates the surface reaction kinetics and thus reduces the overpotential for water oxidation. This study demonstrates a collaborative strategy of interface and surface engineering to design novel structures of α-Fe2O3 based photoanodes for highly efficient solar water oxidation.

11.
Plant Physiol ; 178(1): 402-412, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30026288

RESUMO

Endoplasmic reticulum-associated protein degradation (ERAD) plays an important role in endoplasmic reticulum (ER) quality control. To date, little is known about the retrotranslocation machinery in the plant ERAD pathway. We obtained a DERLIN-like protein (OsDER1) through a SWATH-based quantitative proteomic analysis of ER membrane proteins extracted from ER-stressed rice (Oryza sativa) seeds. OsDER1, a homolog of yeast and mammal DER1, is localized in the ER and accumulates significantly under ER stress. Overexpression or suppression of OsDER1 in rice leads to activation of the unfolded protein response and hypersensitivity to ER stress, and suppression results in floury, shrunken seeds. In addition, the expression levels of polyubiquitinated proteins increased markedly in OsDER1 overexpression or suppression transgenic rice. Coimmunoprecipitation experiments demonstrated that OsDER1 interacted with OsHRD1, OsHRD3, and OsCDC48, the essential components of the canonical ERAD pathway. Furthermore, OsDER1 associated with the signal peptide peptidase, a homolog of a component of the alternative ERAD pathway identified recently in yeast and mammals. Our data suggest that OsDER1 is linked to the ERAD pathway.


Assuntos
Estresse do Retículo Endoplasmático , Degradação Associada com o Retículo Endoplasmático , Retículo Endoplasmático/metabolismo , Proteínas de Membrana/metabolismo , Oryza/metabolismo , Proteínas de Plantas/metabolismo , Ligação Proteica , Proteoma/metabolismo , Proteômica/métodos , Transdução de Sinais , Ubiquitinação , Resposta a Proteínas não Dobradas
12.
Zhonghua Nan Ke Xue ; 25(5): 414-419, 2019 May.
Artigo em Zh | MEDLINE | ID: mdl-32216226

RESUMO

OBJECTIVE: To investigate the surgical techniques and clinical effect of Memokath transurethral spiral thermo-expandable prostatic stent (STEPS) implantation in the treatment of BPH. METHODS: From January 2017 to January 2018, 26 BPH patients underwent Memokath transurethral STEPS implantation, 9 under the flexible cystoscope and the other 17 under the rigid cystoscope. The patients were aged 62-91 years old, with a prostate volume of 32-78 ml, postvoid residual urine volume (PVR) of (67.3 ± 11.2) ml, maximum urinary flow rate (Qmax) of (6.3 ± 1.8) ml/s, and IPSS score of 26.7 ± 5.7. Eight of the patients had preoperative urinary retention, of whom, 6 received catheterization and 2 had undergone cystostomy for bladder fistula before STEPS implantation. RESULTS: The operations lasted 15-30 minutes and were successfully completed in 24 cases while stent-shedding occurred in the other 2. Twenty-two of the patients achieved spontaneous urination immediately after surgery and 2 experienced bladder clot embolism. At 3 month after surgery, 24 of the patients showed significant improvement in PVR (ï¼»21.4 ± 7.7ï¼½ ml), Qmax (ï¼»18.3 ± 4.7ï¼½ ml/s) and IPSS (8.3 ± 2.1), and 13 exhibited no statistically significant difference from the baseline in the IIEF-5 score (14.1 ± 1.1 vs 14.3 ± 1.0, P > 0.05). At 12 months, all the patients were found with markedly improved urination but no adverse events except recurrent urinary tract infection in 2 cases. CONCLUSIONS: Memokath STEPS implantation, with its advantages of simple operation, high safety, definite effectiveness, non-influence on sexual function, is a new effective surgical option for the treatment of BPH.


Assuntos
Cistoscopia/métodos , Hiperplasia Prostática/cirurgia , Stents , Idoso , Idoso de 80 Anos ou mais , Cistoscópios , Humanos , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Resultado do Tratamento , Retenção Urinária
13.
Br J Cancer ; 119(4): 450-461, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-30033448

RESUMO

BACKGROUND: Poor drug response of sorafenib is a major challenge which reduces clinical benefit of renal cell carcinoma (RCC) patients. It is therefore of great clinical significance to elucidate the underlying mechanism to restore the therapeutic response to sorafenib. METHODS: Angiopoietin-like protein 3 (ANGPTL3) protein levels were measured by western blot and immunohistochemistry in two cohorts of RCC patients. Loss-of-function and gain-of-function experiments were performed to investigate the biological roles of ANGPTL3 in response to sorafenib treatment in RCC cells. Human proteome microarray and immunoprecipitation analysis were performed to explore the molecular mechanisms underlying the functions of ANGPTL3. RESULTS: ANGPTL3 was upregulated in sorafenib-responsive RCC, which correlated with clinically good sorafenib response. Knockdown of ANGPTL3 conferred sorafenib-tolerance traits to RCC cells, whereas overexpression of ANGPTL3 restored sorafenib sensitivity in RCC cells. Mechanistically, ANGPTL3 bound to Focal Adhesion Kinase(FAK) and restained sorafenib induced nuclear translocation of FAK, leading to attenuate the ubiquitination of p53, which contributed to cellular apoptosis and enhanced sorafenib response. CONCLUSIONS: ANGPTL3 may be a novel predictor for the response of sorafenib therapy in RCC patients, and a potential target in improving its therapeutic effect.


Assuntos
Proteínas Semelhantes a Angiopoietina/metabolismo , Carcinoma de Células Renais/tratamento farmacológico , Quinase 1 de Adesão Focal/metabolismo , Neoplasias Renais/tratamento farmacológico , Sorafenibe/administração & dosagem , Regulação para Cima , Transporte Ativo do Núcleo Celular/efeitos dos fármacos , Proteína 3 Semelhante a Angiopoietina , Animais , Carcinoma de Células Renais/metabolismo , Carcinoma de Células Renais/patologia , Linhagem Celular Tumoral , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Neoplasias Renais/metabolismo , Neoplasias Renais/patologia , Masculino , Camundongos , Sorafenibe/farmacologia , Resultado do Tratamento , Proteína Supressora de Tumor p53/metabolismo , Ubiquitinação , Ensaios Antitumorais Modelo de Xenoenxerto
14.
Hepatology ; 66(6): 1934-1951, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28714104

RESUMO

The substantial heterogeneity and hierarchical organization in liver cancer support the theory of liver cancer stem cells (LCSCs). However, the relationship between chronic hepatic inflammation and LCSC generation remains obscure. Here, we observed a close correlation between aggravated inflammation and liver progenitor cell (LPC) propagation in the cirrhotic liver of rats exposed to diethylnitrosamine. LPCs isolated from the rat cirrhotic liver initiated subcutaneous liver cancers in nonobese diabetic/severe combined immunodeficient mice, suggesting the malignant transformation of LPCs toward LCSCs. Interestingly, depletion of Kupffer cells in vivo attenuated the LCSC properties of transformed LPCs and suppressed cytokeratin 19/Oval cell 6-positive tumor occurrence. Conversely, LPCs cocultured with macrophages exhibited enhanced LCSC properties. We further demonstrated that macrophage-secreted tumor necrosis factor-α triggered chromosomal instability in LPCs through the deregulation of ubiquitin D and checkpoint kinase 2 and enhanced the self-renewal of LPCs through the tumor necrosis factor receptor 1/Src/signal transducer and activator of transcription 3 pathway, which synergistically contributed to the conversion of LPCs to LCSCs. Clinical investigation revealed that cytokeratin 19/Oval cell 6-positive liver cancer patients displayed a worse prognosis and exhibited superior response to sorafenib treatment. CONCLUSION: Our results not only clarify the cellular and molecular mechanisms underlying the inflammation-mediated LCSC generation but also provide a molecular classification for the individualized treatment of liver cancer. (Hepatology 2017;66:1934-1951).


Assuntos
Transformação Celular Neoplásica , Inflamação/patologia , Neoplasias Hepáticas/metabolismo , Fígado/patologia , Células-Tronco Neoplásicas , Animais , Antígenos de Diferenciação/metabolismo , Antineoplásicos/uso terapêutico , Autorrenovação Celular , Instabilidade Cromossômica , Doença Crônica , Feminino , Humanos , Interleucina-6/fisiologia , Queratina-19/metabolismo , Neoplasias Hepáticas/tratamento farmacológico , Macrófagos/fisiologia , Masculino , Camundongos , Pessoa de Meia-Idade , Niacinamida/análogos & derivados , Niacinamida/uso terapêutico , Compostos de Fenilureia/uso terapêutico , Ratos Wistar , Fator de Transcrição STAT3/metabolismo , Sorafenibe , Fator de Necrose Tumoral alfa/fisiologia , Quinases da Família src/metabolismo
15.
Plant Physiol ; 173(2): 944-955, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27913740

RESUMO

Cuticular waxes are complex mixtures of very-long-chain fatty acids (VLCFAs) and their derivatives, forming a natural barrier on aerial surfaces of terrestrial plants against biotic and abiotic stresses. In VLCFA biosynthesis, ß-ketoacyl-CoA synthase (KCS) is the key enzyme, catalyzing the first reaction in fatty acid elongation and determining substrate specificity. We isolated a rice (Oryza sativa) wax crystal-sparse leaf 4 (WSL4) gene using a map-based cloning strategy. WSL4 is predicted to encode a KCS, a homolog of Arabidopsis (Arabidopsis thaliana) CER6. Complementation of the mutant wsl4-1 with WSL4 genomic DNA rescued the cuticular wax-deficient phenotype, confirming the function of WSL4 The load of wax components longer than 30 carbons (C30) and C28 were reduced markedly in wsl4-1 and wsl4-2 mutants, respectively. Overexpression of WSL4 increased the cuticular wax load in rice leaves. We further isolated a cofactor of WSL4, OsCER2, a homolog of Arabidopsis CER2, by coimmunoprecipitation and confirmed their physical interaction by split-ubiquitin yeast two-hybrid experiments. Expression of WSL4 alone in elo3 yeast cells resulted in increased C24 but did not produce VLCFAs of greater length, whereas expressing OsCER2 alone showed no effect. Coexpression of WSL4 and OsCER2 in elo3 yeast cells yielded fatty acids up to C30. OsCER2 with a mutated HxxxD motif (H172E, D176A, and D176H) interrupted its interaction with WSL4 and failed to elongate VLCFAs past C24 when expressed with WSL4 in elo3 yeast cells. These results demonstrated that WSL4 was involved in VLCFA elongation beyond C22 and that elongation beyond C24 required the participation of OsCER2.


Assuntos
3-Oxoacil-(Proteína de Transporte de Acila) Sintase/metabolismo , Coenzimas/metabolismo , Oryza/enzimologia , Epiderme Vegetal/metabolismo , Folhas de Planta/enzimologia , Proteínas de Plantas/metabolismo , Ceras/metabolismo , Alelos , Motivos de Aminoácidos , Sequência de Aminoácidos , Mapeamento Cromossômico , Clonagem Molecular , Sequência Conservada/genética , Ácidos Graxos/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Técnicas de Inativação de Genes , Mutação/genética , Folhas de Planta/genética , Proteínas de Plantas/química , Proteínas de Plantas/genética , Ligação Proteica , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Saccharomyces cerevisiae/metabolismo , Frações Subcelulares
16.
J Exp Bot ; 69(21): 5029-5043, 2018 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-30107432

RESUMO

Rice glutelins are initially synthesized as 57-kDa precursors at the endoplasmic reticulum (ER) and are ultimately transported into protein storage vacuoles. However, the sequence motifs that affect proglutelin folding, assembly, and their export from the ER remain poorly defined. In this study, we characterized a mutant with nine amino acids deleted in the GluA2 protein, which resulted in specific accumulation of the GluA precursor. The deleted amino acids constitute a well-conserved sequence (LVYIIQGRG) in glutelins and all residues in this motif are necessary for ER export of GluA2. Immunoelectron microscopy and stable transgenic analyses indicated that proglutelins with deletion of this motif misassembled and aggregated through non-native intermolecular disulfide bonds, and were deposited in ER-derived protein bodies (PB-Is), resulting in conversion of PB-Is into a new type of PB. These results indicate that the conserved motif is essential for proper assembly of proglutelin. The correct assembly of proglutelins is critical for their segregation from prolamins in the ER lumen, which is essential for enabling the export of proglutelin from the ER and for the proper formation of PB-Is. We also found that the interchain disulfide bond between acidic and basic subunits is not necessary for their assembly, but it is required for proglutelin folding.


Assuntos
Retículo Endoplasmático/metabolismo , Glutens/genética , Oryza/genética , Proteínas de Plantas/genética , Sequência de Aminoácidos , Sequência de Bases , Sequência Conservada , Endosperma/metabolismo , Glutens/química , Glutens/metabolismo , Oryza/metabolismo , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Alinhamento de Sequência
17.
Mol Cancer ; 16(1): 111, 2017 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-28659173

RESUMO

BACKGROUND: Recent evidences showed that long noncoding RNAs (lncRNAs) are frequently dysregulated and play important roles in various cancers. Clear cell renal cell carcinoma (ccRCC) is one of the leading cause of cancer-related death, largely due to the metastasis of ccRCC. However, the clinical significances and roles of lncRNAs in metastatic ccRCC are still unknown. METHODS: lncRNA expression microarray analysis was performed to search the dysregulated lncRNA in metastatic ccRCC. quantitative real-time PCR was performed to measure the expression of lncRNAs in human ccRCC samples. Gain-of-function and loss-of-function experiments were performed to investigate the biological roles of lncRNAs on ccRCC cell proliferation, migration, invasion and in vivo metastasis. RNA pull-down, RNA immunoprecipitation, chromatin immunoprecipitation, and western blot were performed to explore the molecular mechanisms underlying the functions of lncRNAs. RESULTS: The microarray analysis identified a novel lncRNA termed metastatic renal cell carcinoma-associated transcript 1 (MRCCAT1), which is highly expressed in metastatic ccRCC tissues and associated with the metastatic properties of ccRCC. Multivariate Cox regression analysis revealed that MRCCAT1 is an independent prognostic factor for ccRCC patients. Overexpression of MRCCAT1 promotes ccRCC cells proliferation, migration, and invasion. Depletion of MRCCAT1 inhibites ccRCC cells proliferation, migration, and invasion in vitro, and ccRCC metastasis in vivo. Mechanistically, MRCCAT1 represses NPR3 transcription by recruiting PRC2 to NPR3 promoter, and subsequently activates p38-MAPK signaling pathway. CONCLUSIONS: MRCCAT1 is a critical lncRNA that promotes ccRCC metastasis via inhibiting NPR3 and activating p38-MAPK signaling. Our results imply that MRCCAT1 could serve as a prognostic biomarker and therapeutic target for ccRCC.


Assuntos
Carcinoma de Células Renais/patologia , Neoplasias Renais/patologia , RNA Longo não Codificante/genética , Receptores do Fator Natriurético Atrial/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Idoso , Animais , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/metabolismo , Carcinoma de Células Renais/mortalidade , Linhagem Celular Tumoral , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Renais/genética , Neoplasias Renais/metabolismo , Neoplasias Renais/mortalidade , Masculino , Camundongos Endogâmicos BALB C , Pessoa de Meia-Idade , Prognóstico , Regiões Promotoras Genéticas , Receptores do Fator Natriurético Atrial/genética , Transdução de Sinais , Ensaios Antitumorais Modelo de Xenoenxerto , Proteínas Quinases p38 Ativadas por Mitógeno/genética
18.
Exp Dermatol ; 26(1): 82-84, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27579777

RESUMO

MicroRNAs (miRNAs) play very important roles in the control of immune cell and keratinocyte development and function and are implicated in skin inflammatory diseases, including psoriasis. miRNA miR-17-92 was reported to promote the differentiation of Th1 and Th1 cells and to regulate cell proliferation and apoptosis. Here we showed that imiquimod (IMQ) differentially regulates the expression of miR-17-92 cluster in the mouse skin, upregulating miR-17 and miR-19 families and downregulating miR-92. To investigate whether miR-17-92 cluster is functionally involved in the psoriasis, we have generated three mutant mice with specific deletion or overexpression of miR-17-92 cluster in keratinocytes, or with deletion of miR-17-92 cluster in T cells. Interestingly, deletion or overexpression of miR-17-92 cluster in keratinocytes, or deletion of miR-17-92 in T cells did not significantly affect IMQ-induced psoriasis-like dermatitis development in the mutant mice compared with wild-type littermates. Thus, miRNA miR-17-92 cluster may not be a key factor regulating imiqumod-induced psoriasis-like dermatitis.


Assuntos
MicroRNAs/genética , Psoríase/genética , Aminoquinolinas , Animais , Regulação para Baixo , Imiquimode , Queratinócitos , Camundongos , Camundongos Knockout , Psoríase/induzido quimicamente , Psoríase/patologia , Linfócitos T , Regulação para Cima
19.
Plant Physiol ; 169(4): 2496-512, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26471894

RESUMO

Plastidial disproportionating enzyme1 (DPE1), an α-1,4-d-glucanotransferase, has been thought to be involved in storage starch synthesis in cereal crops. However, the precise function of DPE1 remains to be established. We present here the functional identification of DPE1 in storage starch synthesis in rice (Oryza sativa) by endosperm-specific gene overexpression and suppression. DPE1 overexpression decreased amylose content and resulted in small and tightly packed starch granules, whereas DPE1 suppression increased amylose content and formed heterogeneous-sized, spherical, and loosely packed starch granules. Chains with degree of polymerization (DP) of 6 to 10 and 23 to 38 were increased, while chains with DP of 11 to 22 were decreased in amylopectin from DPE1-overexpressing seeds. By contrast, chains with DP of 6 to 8 and 16 to 36 were decreased, while chains with DP of 9 to 15 were increased in amylopectin from DPE1-suppressed seeds. Changes in DPE1 gene expression also resulted in modifications in the thermal and pasting features of endosperm starch granules. In vitro analyses revealed that recombinant DPE1 can break down amylose into maltooligosaccharides in the presence of Glc, while it can transfer maltooligosyl groups from maltooligosaccharide to amylopectin or transfer maltooligosyl groups within and among amylopectin molecules in the absence of Glc. Moreover, a metabolic flow of maltooligosyl groups from amylose to amylopectin was clearly identifiable when comparing DPE1-overexpressing lines with DPE1-suppressed lines. These findings demonstrate that DPE1 participates substantially in starch synthesis in rice endosperm by transferring maltooligosyl groups from amylose and amylopectin to amylopectin.


Assuntos
Endosperma/enzimologia , Sistema da Enzima Desramificadora do Glicogênio/metabolismo , Oryza/enzimologia , Amido/metabolismo , Amilopectina/metabolismo , Amilose/metabolismo , Metabolismo dos Carboidratos , Endosperma/genética , Expressão Gênica , Sistema da Enzima Desramificadora do Glicogênio/genética , Especificidade de Órgãos , Oryza/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Sementes/enzimologia , Sementes/genética
20.
Lasers Surg Med ; 48(3): 238-44, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26612341

RESUMO

BACKGROUND AND OBJECTIVE: Laser-assisted drug delivery is an emerging technology to achieve greater penetration by existing topical medications to reach desired targets in the tissue. The objective of this research was to study whether laser-assisted delivery of Vitamin C, E, and Ferulic immediately postoperatively of fractional ablative laser could improve wound healing. Secondary objectives were to evaluate the potential molecular markers involved in this wound-healing process. STUDY DESIGN/MATERIAL AND METHODS: A double blinded, prospective, single center, randomized split face trial of Vitamin C, E, and Ferulic topical formula #740019 to decrease postoperative recovery time in fractional ablative laser resurfacing for photo damage. Fifteen healthy men and women of ages 30-55 years were treated with the Vitamin C, E, and Ferulic acid serum to one side of face and vehicle to the other side of face, within 2 minutes immediately after fractional ablative CO2 laser surgery and daily during the healing process. Patients were evaluated daily on days 1-7 using photographs, patient questionnaires, and molecular evaluation. RESULTS: Clinically, postoperative Vitamin C, E, and Ferulic delivery resulted in decreased edema versus vehicle on postoperative day 7 and decreased erythema versus vehicle on postoperative days 3 and 5. Molecularly, the expression of basic fibroblast growth factor (bFGF) was significantly increased at day 5 on the lesion treated with Vitamin C, E, and Ferulic acid serum compared to vehicle control on the other side. CONCLUSION: This is first study to show that Vitamin C, E, and Ferulic acid correlate with more rapid wound healing post-fractional ablative laser. Elevated bFGF could be involved in the Vitamin C, E, and Ferulic acid-induced rapid wound healing.


Assuntos
Antioxidantes/administração & dosagem , Ácido Ascórbico/administração & dosagem , Ácidos Cumáricos/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , Lasers de Gás/uso terapêutico , Vitamina E/administração & dosagem , Cicatrização/efeitos dos fármacos , Adulto , Antioxidantes/farmacologia , Ácido Ascórbico/farmacologia , Biomarcadores/metabolismo , Técnicas Cosméticas , Ácidos Cumáricos/farmacologia , Procedimentos Cirúrgicos Dermatológicos , Método Duplo-Cego , Combinação de Medicamentos , Feminino , Fatores de Crescimento de Fibroblastos/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Estudos Prospectivos , Pele/efeitos dos fármacos , Pele/metabolismo , Envelhecimento da Pele , Resultado do Tratamento , Vitamina E/farmacologia , Cicatrização/fisiologia
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