RESUMEN
Liquid-liquid phase separation (LLPS) plays a key role in the regulation of life activities. Here, we reported a protein from Synechocystis sp. PCC 6803 and annotated as Slr0280. To obtain a water-soluble protein, we deleted the N-terminus transmembrane domain and named it Slr0280Δ. Slr0280Δ with high concentration can undergo LLPS at a low temperature in vitro. It belongs to the phosphodiester glycosidase family of proteins and has a segment of a low-complexity sequence region (LCR), which is thought to regulate the LLPS. Our results show that electrostatic interactions impact the LLPS of Slr0280Δ. We also acquired the structure of Slr0280Δ, which has many grooves on the surface with a large distribution of positive and negative charges. This may be advantageous for the LLPS of Slr0280Δ through electrostatic interactions. Furthermore, the conserved amino acid (arginine at position 531) located on the LCR is important for maintaining the stability of Slr0280Δ as well as LLPS. Our research indicated that the LLPS of proteins can be transformed into aggregation by changing the surface charge distribution.
Asunto(s)
Dominios ProteicosRESUMEN
Although visual feature estimations are accurate and precise, overall estimation errors (i.e., the difference between estimates and actual values) tend to show systematic patterns. For example, estimates of orientations are systematically biased away from horizontal and vertical orientations, showing an oblique illusion. Additionally, many recent studies have demonstrated that estimations of current visual features are systematically biased toward previously seen features, showing a serial dependence. However, no study examined whether the overall estimation errors were correlated with the serial dependence bias. To address this question, we enrolled three groups of participants to estimate orientation, motion speed, and point-light-walker direction. The results showed that the serial dependence bias explained over 20% of overall estimation errors in the three tasks, indicating that we could use the serial dependence bias to predict the overall estimation errors. The current study first demonstrated that the serial dependence bias was not independent from the overall estimation errors. This finding could inspire researchers to investigate the neural bases underlying the visual feature estimation and serial dependence.
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Ilusiones , Percepción Visual , Humanos , Sesgo , Movimiento (Física)RESUMEN
Pigmentation of light-harvesting phycobiliproteins of cyanobacteria requires covalent attachment of open-chain tetrapyrroles, bilins, to the apoproteins. Thioether formation via addition of a cysteine residue to the 3-ethylidene substituent of bilins is mediated by lyases. T-type lyases are responsible for attachment to Cys-155 of phycobiliprotein ß-subunits. We present crystal structures of CpcT (All5339) from Nostoc (Anabaena) sp. PCC 7120 and its complex with phycocyanobilin at 1.95 and 2.50 Å resolution, respectively. CpcT forms a dimer and adopts a calyx-shaped ß-barrel fold. Although the overall structure of CpcT is largely retained upon chromophore binding, arginine residues at the opening of the binding pocket undergo major rotameric rearrangements anchoring the propionate groups of phycocyanobilin. Based on the structure and mutational analysis, a reaction mechanism is proposed that accounts for chromophore stabilization and regio- and stereospecificity of the addition reaction. At the dimer interface, a loop extending from one subunit partially shields the opening of the phycocyanobilin binding pocket in the other subunit. Deletion of the loop or disruptions of the dimer interface significantly reduce CpcT lyase activity, suggesting functional relevance of the dimer. Dimerization is further enhanced by chromophore binding. The chromophore is largely buried in the dimer, but in the monomer, the 3-ethylidene group is accessible for the apophycobiliprotein, preferentially from the chromophore α-side. Asp-163 and Tyr-65 at the ß- and α-face near the E-configured ethylidene group, respectively, support the acid-catalyzed nucleophilic Michael addition of cysteine 155 of the apoprotein to an N-acylimmonium intermediate proposed by Grubmayr and Wagner (Grubmayr, K., and Wagner, U. G. (1988) Monatsh. Chem. 119, 965-983).
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Proteínas Bacterianas/química , Liasas/química , Nostoc/enzimología , Multimerización de Proteína , Proteínas Bacterianas/genética , Sitios de Unión , Cristalografía por Rayos X , Liasas/genética , Nostoc/genética , Estructura Cuaternaria de Proteína , Estructura Secundaria de Proteína , Relación Estructura-ActividadRESUMEN
Allophycocyanin B (AP-B) is one of the two terminal emitters in phycobilisomes, the unique light-harvesting complexes of cyanobacteria and red algae. Its low excitation-energy level and the correspondingly redshifted absorption and fluorescence emission play an important role in funnelling excitation energy from the hundreds of chromophores of the extramembraneous phycobilisome to the reaction centres within the photosynthetic membrane. In the absence of crystal structures of these low-abundance terminal emitters, the molecular basis for the extreme redshift and directional energy transfer is largely unknown. Here, the crystal structure of trimeric AP-B [(ApcD/ApcB)3] from Synechocystis sp. PCC 6803 at 1.75â Å resolution is reported. In the crystal lattice, eight trimers of AP-B form a porous, spherical, 48-subunit assembly of 193â Å in diameter with an internal cavity of 1.1 × 10(6)â Å(3). While the overall structure of trimeric AP-B is similar to those reported for many other phycobiliprotein trimers, the chromophore pocket of the α-subunit, ApcD, has more bulky residues that tightly pack the phycocyanobilin (PCB). Ring D of the chromophores is further stabilized by close interactions with ApcB from the adjacent monomer. The combined contributions from both subunits render the conjugated rings B, C and D of the PCB in ApcD almost perfectly coplanar. Together with mutagenesis data, it is proposed that the enhanced planarity effectively extends the conjugation system of PCB and leads to the redshifted absorption (λmax = 669â nm) and fluorescence emission (679â nm) of the ApcD chromophore in AP-B, thereby enabling highly efficient energy transfer from the phycobilisome core to the reaction centres.
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Ficocianina/química , Synechocystis/química , Sitios de Unión , Dicroismo Circular , Cristalografía por Rayos X , Escherichia coli/genética , Fluorescencia , Modelos Moleculares , Ficobilisomas/química , Ficocianina/genética , Ficocianina/aislamiento & purificación , Ficocianina/metabolismo , Conformación Proteica , Synechocystis/genéticaRESUMEN
The purposes of this study were to investigate the effects of the SASH1 gene on the growth, proliferation, apoptosis, invasiveness, and metastatic potential of lung cancer cells and explore the potential use of SASH1 for the treatment of human lung cancer. The SASH1 gene was cloned into the pcDNA3.1 eukaryotic expression vector, and SASH1 shRNA were designed and constructed. The resulting constructs were transfected into A549 human lung cancer cells, and the changes in the relevant biological characteristics of the cells overexpressing SASH1 and cells with downregulated expression of SASH1 were analyzed using the MTT assay, transwell invasion assay, and flow cytometry. The effects of the SASH1 gene on the expression of cyclin D1, Bcl-2, and MMP-2/9 were also concurrently examined. In the A549 cells from the pcDNA3.1-SASH1 transfected group, cell viability, proliferation, and migration were significantly reduced compared to the control cells (p = 0.039, p = 0.013), and a cell cycle arrest in G1 was observed. The A549 cells transfected with the SASH1 shRNA demonstrated significantly higher cell viabilities, proliferation, and migration compared to the control cells (p = 0.012, p = 0.045). Additionally, the percentage of A549 cells undergoing apoptosis was significantly higher in the pcDNA3.1-SASH1 transfected cells and significantly lower in the SASH1 shRNA transfected cells compared to the control cells (p = 0.010, p = 0.000). The cyclin D1, Bcl-2, and MMP-9/2 protein expression levels were significantly lower in the pcDNA3.1-SASH1-transfected cells and were significantly higher in the SASH1 shRNA-transfected cells than that in the control cells. The SASH1 gene may inhibit A549 cell growth and proliferation as well as promote cellular apoptosis. The overexpression of the SASH1 gene may also be related to the decreased migration of A549 human lung cancer cells.
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Apoptosis/genética , Movimiento Celular/genética , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Proteínas Supresoras de Tumor/genética , Ciclo Celular/genética , Línea Celular Tumoral , Proliferación Celular , Ciclina D1/metabolismo , Expresión Génica , Humanos , Neoplasias Pulmonares/metabolismo , Metaloproteinasa 2 de la Matriz/metabolismo , Metaloproteinasa 9 de la Matriz/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Proteínas Supresoras de Tumor/metabolismoRESUMEN
In Synechocystis sp. PCC 6803, the loop domain (aa 1-70) of the phycobilisome core-membrane linker, L(CM), was found to interact with the glycosyl transferase homolog, Sll1466. Growth of a Sll1466 knock-out mutant was slightly faster in low light, but strongly inhibited in high light; the phenotype is discussed in relation to the regulation of light energy transfer to photosystem II. At the molecular level, the mutant shows the following changes compared to the wild type: (1) a smaller size and higher mobility of phycobilisomes on the thylakoid membrane, and (2) a changed lipid composition of the thylakoid membrane, especially decreased amounts of digalactosyl diacylglycerol. These results indicate a profound regulatory role for Sll1466 in regulating photosynthetic energy transfer.
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Glicosiltransferasas/metabolismo , Luz , Fotosíntesis , Tolerancia a Radiación , Synechocystis/enzimología , Synechocystis/efectos de la radiación , Glicosiltransferasas/química , Glicosiltransferasas/genética , Mutación , Synechocystis/genéticaRESUMEN
Immunoglobulin (Ig) G4-related disease (IgG4-RD) is a rare and chronic progressive clinical entity, characterized by elevated serum IgG4 along with tissue infiltration by IgG4 + plasma cells. It is an immune-mediated fibro-inflammatory condition that can affect virtually any organ and tissue. IgG4-related lung disease (IgG4-RLD) occupies 14% of all IgG4-RD, with nonspecific symptoms and various abnormal radiographic patterns. Published data on IgG4-related hypertrophic pachymeningitis (IgG4-RHP), an increasingly recognized central nervous system manifestation of IgG4-RD, is also limited. Both lung and cranial dura involvement have not yet been reported until now. We further entail a review of the literature on the clinicopathologic features and differential diagnosis of this uncommon disease. We herein report an interesting case of a 70-year-old male patient admitted due to headache and fever. A magnetic resonance imaging (MRI) of the brain revealed extensive dural thickening with marked enhancement. Chest computed tomography (CT) scan showed nodular or mass-like consolidation and focal interstitial change. Thoracoscopic lung biopsy and lumbar puncture were conducted. After careful histopathological observation and consideration of alternative differential diagnoses, he was diagnosed with IgG4-related disease with lung and cranial dural involvement based upon significant elevation of serum and cerebrospinal fluid (CSF) IgG4 concentration. The patient was started on oral prednisolone 60 mg/day (1.0 mg/kg/day) for 14 days, and a tapering dose of 5 mg every 2 weeks followed by maintenance therapy at low dose for 3 months. His clinical manifestations, and serologic and imaging findings improved with steroid treatment. Currently, the patient remains well without disease progression. IgG4-RD should be considered as a differential when diagnosing other similar multisystemic lesions. Clinical examination, careful histological observation, and immunostaining for appropriate markers are essential in establishing the diagnosis. Clinicians should become familiar with this alternative differential diagnosis.
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Enfermedad Relacionada con Inmunoglobulina G4/diagnóstico , Enfermedad Relacionada con Inmunoglobulina G4/terapia , Anciano , Biomarcadores , Biopsia , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Manejo de la Enfermedad , Susceptibilidad a Enfermedades , Humanos , Enfermedad Relacionada con Inmunoglobulina G4/etiología , Enfermedad Relacionada con Inmunoglobulina G4/metabolismo , Inmunohistoquímica , Inmunosupresores/administración & dosificación , Inmunosupresores/uso terapéutico , Pulmón/diagnóstico por imagen , Pulmón/patología , Imagen por Resonancia Magnética , Masculino , Evaluación de Síntomas , Tomografía Computarizada por Rayos X , Resultado del TratamientoRESUMEN
OBJECTIVE: The aim of this study was to investigate the effect of thalidomide on the growth of human hepatoma cell line SMMC-7721 cells in vitro, and to explore the curative possibility of hepatocellular carcinoma with thalidomide. METHODS: SMMC-7721 cells were treated with Thalidomide at different concentrations. The cell growth and proliferation was assessed by MTT assay. DNA ladder, apoptosis rate and changes of cell nuclei were studied by agarose electrophresis, fluorescence microscopy and flow cytometry, respectively. The expression of caspase-3 was analyzed with flow cytometry. The VEGF content of SMMC-7721 cells in culture medium was tested by ELSIA. RESULTS: When the concentration of Thalidomide solution was increased from 3.125 microg/ml to 200 microg/ml, the cell growth was inhibited by from 11.7% to 34.2%. Compared with the control group, the thalidomide solution at a concentration of 25, 50, 100 and 200 microg/ml solution significantly inhibited the proliferation of SMMC-7721 cells (P < 0.05). A ladder pattern of DNA fragments appeared after SMMC-7721 cells exposed to 200 microg/ml thalidomide for 24 h, especially for 48 h. Fluorescence microscopy revealed that the cell nuclei were condensed and fragmented after the cells were exposed to 200 microg/ml thalidomide for 48 h. In cells treated with 200 microg/ml thalidomide for 12, 24, 48 and 72 h, the apoptotic rate was 3.1% +/- 0.5%, 8.4% +/- 1.3%, 19.4% +/- 3.5% and 25.8% +/- 2.1%, respectively, significantly higher than that in the negative control group 1.6% +/- 0.6%. The cells treated with thalidomide at a concentration of 50, 100, 200 microg/ml for 48 h, the apoptotic rate was 8.7% +/- 1.2%, 16.8% +/- 2.5% and 25.4% +/- 4.5%, respectively, increasing in a dose-dependent manner, also significantly than that in the cells of control group 2.1% +/- 0.5%, (all were P < 0.05). The caspase-3 positivity of SMMC-7721 cells treated with thalidomide was increasing along with the increase of treatment time or drug concentration, but not in the control cells. The VEGF content in SMMC-7721 cells was lowering when thalidomide was used in an increasing concentration. CONCLUSION: Under the conditions used in this study, thalidomide can inhibit the proliferation of SMMC-7721 cells in vitro. Induction of apoptosis and inhibition of angiogenesis may be possibly two mechanisms for its anticancer action.
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Carcinoma Hepatocelular/patología , Proliferación Celular/efectos de los fármacos , Neoplasias Hepáticas/patología , Talidomida/farmacología , Inhibidores de la Angiogénesis/administración & dosificación , Inhibidores de la Angiogénesis/farmacología , Apoptosis/efectos de los fármacos , Carcinoma Hepatocelular/metabolismo , Caspasa 3/metabolismo , Línea Celular Tumoral , Relación Dosis-Respuesta a Droga , Humanos , Neoplasias Hepáticas/metabolismo , Talidomida/administración & dosificación , Factor A de Crecimiento Endotelial Vascular/metabolismoRESUMEN
The objective was to assess the safety and outcome of cold snare technique used by flexible bronchoscopy in the treatment of airway benign neoplasms. The clinical data of 21 patients, who had airway benign neoplasm and were treated through the cold snare method in Sir Run Run Shaw Hospital, affiliated with the Zhejiang University, were retrospectively analyzed. The relief of the symptoms and occurrence of complications were observed and evaluated. All the tumors were benign and removed by cold snare. Postoperatively, we found that the treatment was completely effective in 12 patients, and there was a significant improvement in 7 patients and a moderate improvement in 2 patients, and no recurrence in follow-up visit. In conclusion, the cold snare technique is an economically feasible, safe, and effective method in the treatment of airway neoplasms.
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Broncoscopía/métodos , Neoplasias Pulmonares/cirugía , Pulmón/cirugía , Tráquea/cirugía , Neoplasias de la Tráquea/cirugía , Pliegues Vocales/cirugía , Adulto , Anciano , Femenino , Humanos , Pulmón/patología , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Tráquea/patología , Resultado del Tratamiento , Pliegues Vocales/patologíaRESUMEN
Cyanobacteria are among the main contributors to global photosynthesis and show a high degree of metabolic plasticity. Synechocystis sp. PCC 6803 can grow under photoautotrophic, photomixotrophic or photoheterotrophic conditions. We have characterized a novel periplasmic protein (Slr0280) that tunes the photomixotrophic growth of Synechocystis sp. PCC 6803. Slr0280 is a multi-domain protein consisting mainly of ß-sheets. Several proteins that interact with Slr0280 were identified via bacterial two-hybrid screening. Slr0280 may interact through its DUF2233 domain with partners that participate in sugar metabolism, thereby coordinating the respective regulations. When slr0280 was deleted, the mutant grew more slowly than wild-type in the presence of glucose, which is ascribed to the down-regulation of glycolysis, glycogen catabolism, oxidative pentose phosphate pathway, Calvin cycle and glucose utilization. A positive regulation of Slr0280 on these sugar catabolic enzymes was confirmed by transcript (qPCR) analyses. Based on these findings, we proposed a speculative model that Slr0280 plays a coordinating regulatory role in sugar metabolism.
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Glucólisis/fisiología , Vía de Pentosa Fosfato/fisiología , Proteínas Periplasmáticas , Fotosíntesis/fisiología , Synechocystis , Glucosa/genética , Glucosa/metabolismo , Glucógeno/genética , Glucógeno/metabolismo , Proteínas Periplasmáticas/genética , Proteínas Periplasmáticas/metabolismo , Estructura Secundaria de Proteína , Synechocystis/genética , Synechocystis/metabolismoRESUMEN
BACKGROUND: MicroRNA-124 (miR-124) has been reported to be downregulated in breast cancer. However, its clinical significance and prognostic value in breast cancer have not been extensively studied. METHODS: The tissue expression levels of miR-124 were measured using quantitative real-time PCR in 133 breast cancer patients. The correlation between the miR-124 levels and the clinicopathological factors of the patients was also analyzed. Survival and Cox proportional-hazards regression analyses were performed to determine the correlation between miR-124 expression levels and prognosis in the patients. RESULTS: Quantitative real-time PCR analysis showed that miR-124 had lower expression in breast cancer specimens than that in matched adjacent normal breast tissues (0.39 ± 0.16 vs. 1.00 ± 0.39; P < 0.05). Low miR-124 expression level was significantly associated with advanced TNM stage (P = 0.011), lymph node metastasis (P = 0.012), and poorer pathological differentiation (P = 0.023). A significant difference was found that breast cancer patients with low miR-124 expression level had distinctly shorter overall survival than patients with high miR-124 expression level (63.8% vs. 35.2%, P = 0.03). Furthermore, multivariate analysis of the prognosis factors with a Cox proportional hazards model confirmed that low miR-124 expression was a significant independent predictor of poor survival in breast cancer (HR = 3.16, 95% CI: 1.79-9.13, P = 0.017). CONCLUSION: These findings proved that the decreased expression of miR-124 might be associated with tumor progression and poor prognosis in patients with breast cancer. VIRTUAL SLIDES: The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/3752603721493544.
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Biomarcadores de Tumor/genética , Neoplasias de la Mama/genética , Carcinoma/genética , MicroARNs/genética , Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/patología , Neoplasias de la Mama/terapia , Carcinoma/mortalidad , Carcinoma/patología , Carcinoma/secundario , Carcinoma/terapia , Diferenciación Celular , Distribución de Chi-Cuadrado , Regulación hacia Abajo , Femenino , Humanos , Estimación de Kaplan-Meier , Metástasis Linfática , Persona de Mediana Edad , Análisis Multivariante , Estadificación de Neoplasias , Valor Predictivo de las Pruebas , Modelos de Riesgos Proporcionales , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Factores de RiesgoRESUMEN
Glomus tumor is an exceedingly rare neoplasm that is derived from cells of the neuromyoarterial glomus or glomus body. It rarely occurs in the visceral organs where glomus body may be sparse or even absent, such as the stomach, intestines, mediastinum, and respiratory tract. It is unusual for a glomus tumor to demonstrate atypical or malignant histopathological characteristics. It is also rare for such a tumor to express clinically aggressive behavior. However, when metastasis does occur, this disease is often fatal. We herein report an interesting case of a middle-age woman admitted due to progressive cough and hemoptysis. A polypoid mass was found to occlude the left lingular lobar bronchus. Final histopathologic examination showed the presence of malignant glomus tumor, confirmed by immunoreactivity for smooth muscle actin and vimentin. Two months later, the patient developed abdominal distension and gastrointestinal bleeding. Further evaluation lead to the discovery of widespread metastatic disease to the gastrointestinal tract, spleen, and the left adrenal gland. We further entail a review of the literature on the clinicopathologic features and diagnosis of this uncommon tumor.
RESUMEN
BACKGROUND: The aim of the present study was to measure the serum level of dickkopf-1(DKK-1) in patients with non-small cell lung cancer (NSCLC), and to determine the prognostic potential of serum DKK-1 in NSCLC. MATERIAL AND METHODS: The present study included a total of 150 patients with NSCLC and 150 healthy controls. Serum level of DKK-1 was measured by enzyme-linked immunosorbent assay (ELISA). Numerical variables were recorded as means ± standard deviation (SD) and analyzed by independent t-tests. Categorical variables were presented as rates and analyzed by using the chi-square test or Fisher's exact test. The overall survival was analyzed by log-rank test, and survival curves were plotted according to Kaplan-Meier. RESULTS: We found that serum DKK-1 level was significantly higher in patients with NSCLC than healthy controls. Mean serum DKK-1 level was 31.42 ± 6.32 ng/ml in the NSCLC group and 14.12 ± 3.29 ng/ml in the healthy control group (p <0.01). Serum DKK-1 level expression level was significantly positively correlated with TNM stage (p = 0.009), lymph node involvement(p = 0.001), and distant metastases(p < 0.001).In the multivariate Cox proportional hazards analysis, high DKK-1 expression was independently associated with poor survival (P < 0.001; HR = 3.98; 95% CI =2.19-4.83). CONCLUSIONS: In conclusion, our results showed that DKK-1 was overexpressed in NSCLC, and DKK-1 in serum was a good predictor of poor prognosis in patients with NSCLC. More researches are needed in the future to clarify the detailed mechanism of DKK-1 in the carcinogenesis and metastasis of NSCLC. VIRTUAL SLIDES: The virtual slides for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1471414150119415.
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Biomarcadores de Tumor/sangre , Carcinoma de Pulmón de Células no Pequeñas/sangre , Péptidos y Proteínas de Señalización Intercelular/sangre , Neoplasias Pulmonares/sangre , Adulto , Anciano , Carcinoma de Pulmón de Células no Pequeñas/mortalidad , Carcinoma de Pulmón de Células no Pequeñas/patología , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Estimación de Kaplan-Meier , Neoplasias Pulmonares/mortalidad , Neoplasias Pulmonares/patología , Masculino , Pronóstico , Modelos de Riesgos ProporcionalesRESUMEN
Primaquine, an 8-aminoquinoline, is the only drug which cures the dormant hypnozoites of persistent liver stages from P. vivax. Increasing resistance needs the discovery of alternative pathways as drug targets to develop novel drug entities. Deoxyhypusine hydroxylase (DOHH) completes hypusine biosynthesis in eukaryotic initiation factor (eIF-5A) which is the only cellular protein known to contain the unusual amino acid hypusine. Modified EIF-5A is important for proliferation of the malaria parasite. Here, we present the first successful cloning and expression of DOHH from P. vivax causing tertiary malaria. The nucleic acid sequence of 1041 bp encodes an open reading frame of 346 amino acids. Histidine tagged expression of P. vivax DOHH detected a protein of 39.01 kDa in E. coli. The DOHH protein from P. vivax shares significant amino acid identity to the simian orthologues from P. knowlesi and P. yoelii strain H. In contrast to P. falciparum only four E-Z-type HEAT-like repeats are present in P. vivax DOHH with different homology to phycocyanin lyase subunits from cyanobacteria and in proteins participating in energy metabolism of Archaea and Halobacteria. However, phycocyanin lyase activity is absent in P. vivax DOHH. The dohh gene is present as a single copy gene and transcribed throughout the whole erythrocytic cycle. Specific inhibition of recombinant P. vivax DOHH is possible by complexing the ferrous iron with zileuton, an inhibitor of mammalian 5-lipoxygenase (5-LOX). Ferrous iron in the active site of 5-LOX is coordinated by three conserved histidines and the carboxylate of isoleucine(673). Zileuton inhibited the P. vivax DOHH protein with an IC50 of 12,5 nmol determined by a relative quantification by GC/MS. By contrast, the human orthologue is only less affected with an IC50 of 90 nmol suggesting a selective iron-complexing strategy for the parasitic enzyme.
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Oxigenasas de Función Mixta/genética , Oxigenasas de Función Mixta/metabolismo , Plasmodium vivax/enzimología , Plasmodium vivax/genética , Secuencia de Aminoácidos , Animales , Araquidonato 5-Lipooxigenasa/metabolismo , Clonación Molecular , Análisis por Conglomerados , Activación Enzimática , Expresión Génica , Humanos , Hidroxiurea/análogos & derivados , Hidroxiurea/farmacología , Inhibidores de la Lipooxigenasa/farmacología , Malaria Vivax/parasitología , Oxigenasas de Función Mixta/química , Oxigenasas de Función Mixta/aislamiento & purificación , Datos de Secuencia Molecular , Ficocianina/metabolismo , Plasmodium vivax/clasificación , Plasmodium vivax/efectos de los fármacos , Alineación de Secuencia , Transcripción GenéticaRESUMEN
Nkx2-1 (Nkx homeobox-1 gene), also known as TTF-1 (thyroid transcription factor-1), is a tissue-specific transcription factor of the thyroid, lung, and ventral forebrain. While it has been shown to play a critical role in lung development and lung cancer differentiation and morphogenesis, molecular mechanisms mediating Nkx2-1 cell- and tissue-specific expression in normal and cancerous lungs have yet to be fully elucidated. The recent identification of prognostic biomarkers in lung cancer, particularly in lung adenocarcinoma (ADC), and the different reactivity of patients to chemotherapeutic drugs have opened new avenues for evaluating patient survival and the development of novel effective therapeutic strategies. The function of Nkx2-1 as a proto-oncogene was recently characterized and the gene is implicated as a contributory factor in lung cancer development. In this review, we summarize the role of this transcription factor in the development, diagnosis, and prognosis of lung cancer in the hope of providing insights into the utility of Nkx2-1 as a novel biomarker of lung cancer.