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1.
Front Nutr ; 10: 1286209, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38094925

RESUMEN

To investigate the protective effect of blackberry anthocyanins (BA), tea polyphenols (TP), and their binary mixture on the oxidative stability of edible oils during storage, BA, TP, and their binary mixture were added to lard and olive oil. The changes in peroxide value (PV), thiobarbituric acid reactive substances (TBARS), acid value (AV), and scavenging capacity of DPPH and ABTS•+ of oil samples were evaluated during accelerated storage. BA were found to have a remarkable capability to enhance antioxidant properties, delay lipid oxidation, and inhibit the deterioration both of lard and olive oil at high-temperature processes. Furthermore, the antioxidant synergistic effect of BA and TP was found both in lard and olive oil for the first time. All these results suggested that BA and its combination with TP might possess the potential value to protect the quality of edible oils.

2.
Front Nutr ; 10: 1172982, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37275633

RESUMEN

The dual epidemic of obesity and diabetes mellitus is becoming an important worldwide public health issue. "Diabesity" is the term used to describe the combined detrimental health effects of both diabetes mellitus and obesity/overweight. Currently, food-derived bioactive compounds are suggested to alleviate diabesity. Blueberries are rich in bioactive anthocyanins, which are associated with contributing to preventing obesity and diabetes mellitus. However, the accurate active compounds and the underlying mechanism are still unclear. The objective of this study was to investigate the beneficial effects of blueberry anthocyanin on diabesity. In total, five anthocyanins (delphinidin-3-O-galactoside, delphinidin-3-O-glucoside, petunidin-3-O-galactoside, petunidin-3-O-glucoside, and malvidin-3-O-galactoside) were isolated from rabbiteye blueberry (Vaccinium virgatum) cultivar "Garden blue." All these anthocyanins exhibited oxygen radical absorbance capacity (ORAC), scavenging power of ABTS+, and DPPH-free radical and inhibitory activity of α-glucosidase in vitro. Moreover, some compounds improved glucose uptake and attenuated lipid accumulation in high glucose and oleic acid-treated HepG2 cells. All these results suggest that blueberry anthocyanins have potential antioxidant, hypoglycemic, and hypolipidemic effects, which may benefit the treatment of diabesity.

3.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 31(3): 649-653, 2023 Jun.
Artículo en Chino | MEDLINE | ID: mdl-37356921

RESUMEN

OBJECTIVE: To explore the efficacy of tyrosine kinase inhibitor (TKI) combined with decitabine, homoharringtonine, and interferon regimen as maintenance therapy for blast phase chronic myeloid leukemia (CML-BP). METHODS: The clinical data of CML-BP patients who received the first major hematological response after induction therapy at The Affiliated Cancer Hospital of Zhengzhou University from June 2015 to December 2021 were analyzed retrospectively. The event-free survival, duration of remission, and overall survival of patients in TKI combined with decitabine, homoharringtonine, interferon group(n=18) and TKI combined with conventional chemotherapy group(n=10) were compared by log-rank test. RESULTS: A total of 28 patients were included, with a median age of 46 (24-58) years old. Kaplan-Meier survival analysis showed that patients in TKI combined with decitabine, homoharringtonine, interferon group had longer event-free survival (7.4 vs 4.3 months, P=0.043, HR=0.44, 95% CI: 0.17-1.14), duration of overall remission (16.1 vs 6.6 months, P=0.005, HR=0.32, 95% CI: 0.11-0.89), overall survival (34.3 vs 13.5 months, P=0.006, HR=0.29, 95% CI: 0.10-0.82) compared with patients in TKI combined with conventional chemotherapy group. CONCLUSION: The TKI combined with decitabine, homoharringtonine and interferon regimen can significantly prolong the survival of CML-BP patients who obtained the major hematological response compared with TKI combined with conventional chemotherapy regimen.


Asunto(s)
Crisis Blástica , Interferones , Humanos , Persona de Mediana Edad , Crisis Blástica/tratamiento farmacológico , Homoharringtonina/uso terapéutico , Decitabina/uso terapéutico , Interferones/uso terapéutico , Estudios Retrospectivos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Inhibidores de Proteínas Quinasas/uso terapéutico , Resultado del Tratamiento
4.
Chem Sci ; 13(40): 11896-11903, 2022 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-36320898

RESUMEN

Local flexibility in a metal-organic framework is intriguing for reconstructing a microenvironment to distinguish different guest molecules by emphasizing their differences. Herein, guest-adaptive flexibility is observed in a metal-organic framework for efficiently discriminating aromatic isomers. Microcrystal electron diffraction directly reveals that the anthracene rings can rotate around the single bond with the adsorption of guest molecules. Disorder transformation of the ligand enables the preferential adsorption of ethylbenzene over other xylene isomers. Especially, a coated capillary column combining single/multi-component adsorption confirms a unique separation order of ethylbenzene > p-xylene > m-xylene > o-xylene with excellent selectivities, which has not been reported in other materials. Density functional theory calculations and the calculated Hirshfeld surface of guest molecules in the framework demonstrate that a guest-induced splint-like confinement structure makes the main contribution to such separation performance. This finding will provide a rational strategy for molecular recognition utilizing the local flexibility of metal-organic frameworks.

5.
Zhongguo Zhong Yao Za Zhi ; 47(17): 4789-4798, 2022 Sep.
Artículo en Chino | MEDLINE | ID: mdl-36164886

RESUMEN

This study discusses the effect of Biyanning Granules on local symptoms and systemic immune function of patients with chronic rhinosinusitis with nasal polyps(CRSwNP) within the 6 months of treatment by glucocorticoid nasal spray after surgical treatment. To be specific, a total of 237 CRSwNP patients, treated in Otorhinolaryngology Head and Neck Surgery in Shanxi Bethune Hospital, were enrolled. All patients were treated by nasal endoscopy and classified into hormone group(Budesonide Nasal Spray after surgery), Chinese medicine group(Biyanning Granules after surgery), and combination group(Budesonide Nasal Spray+Biyanning Granules after surgery) with random number table method, 79 cases in each group, and the treatment lasted 3 months. The follow-up was performed from the day of discharge to 12 months after the surgery. The clinical effect was observed. The visual analogue scale(VAS) scores and sino-nasal outcome test-20(SNOT-20) scale scores were used to assess patient's subjective symptoms and quality of life. Lund-Kennedy endoscopic score(LKES), Japanese T&T olfactometry, and standard olfactory test were used to evaluate the objective curative effect on patients. The levels of interleukin(IL)-21, CD4~+CD25~+Foxp3~+Treg, and CD4~+Th17 in peripheral blood were analyzed. The incidence of complications, recurrence rate, and adverse reactions during treatment were also recorded. The total effective rate after treatment in the combination group was higher than that in the hormone group and Chinese medicine group(P<0.05). VAS scores and SNOT-20 scale scores were lower in the three groups after treatment than before treatment and lower in the combination group than in the other two groups(P<0.05). The improvement in LKES and T&T standard olfactometry test was better in the combination group than in the other two groups(P<0.05). Serum levels of IL-21 and CD4~+Th17 in the three groups were lower than before treatment. The levels in the combination group were lower than those in the other two groups and lower in the hormone group than in the Chinese medicine group(P<0.05). Serum CD4~+CD25~+Foxp3~+Treg level was higher in the three groups after treatment than before, higher in the combination group than in the other two groups, and higher in the Chinese medicine group than in the hormone group(P<0.05). During the treatment, no serious adverse reactions were observed. After treatment, the combination group showed no significant difference in the incidence and recurrence rate of complications from the hormone group and Chinese medicine group. In the treatment of CRSwNP with glucocorticoid, Biyanning Granules reduced the side effects of glucocorticoid and assisted glucocorticoid in alleviating the symptoms of patients. It significantly improved the curative effect, regulated immune imbalance, accele-rated the recovery of immune function, reduced the recurrence rate of inflammatory reaction, and improved the quality of life. The combination of Chinese and western treatment is more effective than glucocorticoid alone and warrants further clinical study in large sample size.


Asunto(s)
Medicina Tradicional China , Rinitis , Sinusitis , Budesonida/uso terapéutico , Enfermedad Crónica , Factores de Transcripción Forkhead/metabolismo , Glucocorticoides/uso terapéutico , Humanos , Inmunidad , Rociadores Nasales , Calidad de Vida , Rinitis/tratamiento farmacológico , Rinitis/inmunología , Rinitis/cirugía , Sinusitis/tratamiento farmacológico , Sinusitis/inmunología , Sinusitis/cirugía
6.
Nat Commun ; 11(1): 2656, 2020 05 27.
Artículo en Inglés | MEDLINE | ID: mdl-32461609

RESUMEN

The earthworm is particularly fascinating to biologists because of its strong regenerative capacity. However, many aspects of its regeneration in nature remain elusive. Here we report chromosome-level genome, large-scale transcriptome and single-cell RNA-sequencing data during earthworm (Eisenia andrei) regeneration. We observe expansion of LINE2 transposable elements and gene families functionally related to regeneration (for example, EGFR, epidermal growth factor receptor) particularly for genes exhibiting differential expression during earthworm regeneration. Temporal gene expression trajectories identify transcriptional regulatory factors that are potentially crucial for initiating cell proliferation and differentiation during regeneration. Furthermore, early growth response genes related to regeneration are transcriptionally activated in both the earthworm and planarian. Meanwhile, single-cell RNA-sequencing provides insight into the regenerative process at a cellular level and finds that the largest proportion of cells present during regeneration are stem cells.


Asunto(s)
Perfilación de la Expresión Génica/métodos , Oligoquetos/genética , Regeneración/genética , Animales , Diferenciación Celular/genética , Proliferación Celular/genética , Oligoquetos/citología , Oligoquetos/metabolismo , RNA-Seq/métodos , Regeneración/fisiología , Elementos Reguladores de la Transcripción/genética , Secuenciación del Exoma , Secuenciación Completa del Genoma
7.
Chemistry ; 26(45): 10307-10313, 2020 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-32363612

RESUMEN

Recently, 2D organic-inorganic hybrid lead halide perovskites have attracted intensive attention in solid-state luminescence fields such as single-component white-light emitters, and rational optimization of the photoluminescence (PL) performance through accurate structural-design strategies is still significant. Herein, by carefully choosing homologous aliphatic amines as templates, isotypical perovskites [DMEDA]PbCl4 (1, DMEDA=N,N-dimethylethylenediamine) and [DMPDA]PbCl4 (2, DMPDA=N,N-dimethyl-1,3-diaminopropane) having tunable and stable broadband bluish white emission properties were rationally designed. The subtle regulation of organic cations leads to a higher degree of distortion of the 2D [PbCl4 ]2- layers and enhanced photoluminescence quantum efficiencies (<1 % for 1 and 4.9 % for 2). The broadband light emissions could be ascribed to self-trapped excitons on the basis of structural characterization, time-resolved PL, temperature-dependent PL emission, and theoretical calculations. This work gives a new guidance to rationally optimize the PL properties of low-dimensional halide perovskites and affords a platform to probe the structure-property relationship.

8.
Inorg Chem ; 58(15): 10304-10312, 2019 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-31328509

RESUMEN

In recent years, although low-dimensional hybrid lead halides have received great attention due to the fascinating photoluminescent (PL) properties, the research is still on the early stage and only limited phases have been explored and characterized. Here, by introducing heterometals as mixed structural compositions and optical activity centers, we prepared a series of low-dimensional hybrid heterometallic halides, namely as, [(Me)-DABCO]2Cu2PbI6, [(Me)2-DABCO]2M5Pb2I13 (M = Cu and Ag) and [(Me)2-DABCO]Ag2PbBr6 (Me = methyl group, DABCO = 1,4-diazabicyclo[2.2.2]octane). These hybrid halides feature a low-dimensional 0D [Cu2PbI6]2- cluster, a 1D [M5Pb2I13]4- chain, and a 2D [Ag2PbBr6]2- layer, respectively, on the basis of corner-, edge- and face-sharing connecting of [MX4] tetrahedrons, [PbX5] quadrangular pyramids, and [PbX6] octahedrons. Under the photoexcitation, these hybrid heterometallic halides exhibit deep-red luminescent emissions from 711 to 801 nm with the largest Stocks shift of 395 nm. The temperature-dependent PL emissions, PL lifetime, and theoretical calculations are also investigated to probe into the intrinsic nature of photoluminescent emissions. This work affords new types of hybrid halides by introducing different metal centers to probe into the structural evolution and photoluminescent properties.

10.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 26(5): 1414-1419, 2018 Oct.
Artículo en Chino | MEDLINE | ID: mdl-30295260

RESUMEN

OBJECTIVE: To analyze the clinical efficacy and possible influencing factors of autologous hematopoietic Stem cell transplantation (auto-HSCT) in the treatment of patients with multiple myeloma (MM). METHODS: Clinical data of 40 MM patients received auto-HSCT in the Department of Hematology of Henan Cancer Hospital from September 2010 to November 2017 were retrospectively analyzed, the clinical curative efficiency was summarized and the related factors were analyzed. RESULTS: The curative efficiency of the patients before transplantation was 9(22.5%) with complete remission(CR), 5(12.5%) with very good partial remission(VGPR), 26(65%) with partial remission(PR), respectively, one of them was PR after 3 recurrences. The curative efficiency after transplantation was 22(55%) with complete remission(CR), 12(30%) with very good partial remission(VGPR), 6(15%) with partial remission(PR), respectively. And 2 cases were CR after double transplantation. Median follow-up time was 28.4 (3.1 to 88) months,15 cases presented disease progression, 7 cases were dead, 3-year estimated progression-free survival(PFS) and overall survival(OS) rate were 45.1% and 82% respectively. Unvariate analysis showed that the OS was affected by ISS stage (P<0.05), CR and VGPR (P<0.05) after transplantation; PFS was affected by ISS stage (P<0.01), before transplantation induction therapy (27 cases with bortezomizomi or thalidomide) (P<0.05), disease risk stratification (6 cases in high risk group) (P<0.05) , CR and VGPR (P<0.05) before transplantation, CR and VGPR (P<0.01) after transplantation. Cox multivariate regression analysis showed that the independent prognostic factors for OS were ISS stage, CR and VGPR after transplantation; the independent prognostic factors for PFS were the CR, VGPR, ISS stage after transplantation and induction therapy before transplant. CONCLUSION: Auto-HSCT can improve the clinical efficacy and survival rate of MM patients; ISS stage, CR and VGPR after transplantation are independent prognostic factors for OS and PFS, and induction therapy before transplantation is also an independent prognostic factor for PFS.


Asunto(s)
Mieloma Múltiple , Recurrencia Local de Neoplasia , Protocolos de Quimioterapia Combinada Antineoplásica , Supervivencia sin Enfermedad , Trasplante de Células Madre Hematopoyéticas , Humanos , Mieloma Múltiple/terapia , Pronóstico , Inducción de Remisión , Estudios Retrospectivos , Trasplante Autólogo
11.
Anal Chim Acta ; 904: 58-64, 2016 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-26724763

RESUMEN

Herein, a novel electrochemiluminescence resonance energy transfer (ECL-RET) biosensor using graphene quantum dots (GQDs) as donor and graphene oxide (GO) as acceptor for monitoring the activity of protein kinase was presented for the first time. Anti-phosphoserine antibody conjugated graphene oxide (Ab-GO) nonocomposite could be captured onto the phosphorylated peptide/GQDs modified electrode surface through antibody-antigen interaction in the presence of casein kinase II (CK2) and adenosine 5'-triphosphate (ATP), resulting in ECL from the GQDs quenching by closely contacting GO. This ECL quenching degree was positively correlated with CK2 activity. Therefore, on the basis of ECL-RET between GQDs and GO, the activity of protein kinase can be detected sensitively. This biosensor can also be used for quantitative analysis CK2 activity in serum samples and qualitative screening kinase inhibition, indicating the potential application of the developed method in biochemical fundamental research and clinical diagnosis.


Asunto(s)
Técnicas Electroquímicas , Grafito/química , Luminiscencia , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Quinasas/metabolismo , Puntos Cuánticos , Técnicas Biosensibles , Reproducibilidad de los Resultados
12.
Chem Commun (Camb) ; 51(63): 12669-72, 2015 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-26160048

RESUMEN

A novel Au NP mediated dual-potential ECL ratiometric approach for highly sensitive protein kinase activity and inhibition assay has been developed based on the simultaneous decrease of cathodic ECL from GQDs and enhancement of anodic ECL from luminol in the same bioanalysis.


Asunto(s)
Grafito/química , Mediciones Luminiscentes , Luminol/análisis , Proteínas Quinasas/metabolismo , Puntos Cuánticos/química , Biocatálisis , Técnicas Electroquímicas , Electrodos , Oro/química , Nanopartículas del Metal/química
13.
Biosens Bioelectron ; 63: 458-464, 2015 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-25129507

RESUMEN

DNA methyltransferases catalyze the transfer of a methyl group from S-adenosylmethionine to the target adenine or cytosine, eventually inducing the DNA methylation in both prokaryotes and eukaryotes. Herein, we developed a novel electrochemiluminescence biosensor to quantify DNA adenine methylation (Dam) methyltransferase (MTase) employing signal amplification of GO/AgNPs/luminol composites to enhance the assay sensitivity. The method was developed by designing a capture probe DNA, which was immobilized on gold electrode surface, to hybridize with azide complementary DNA to form the azide-terminated dsDNA. Then, alkynyl functionalized GO/AgNPs/luminol composites as the signal probe were immobilized to azide-terminated dsDNA modified electrode via click chemistry, resulting in a high electrochemiluminescence (ECL) signal. Once the DNA hybrid was methylated (under catalysis of Dam MTase) and further cleaved by Dpn I endonuclease (a site-specific endonuclease recognizing the duplex symmetrical sequence of 5'-G-Am-T-C-3'), GO/AgNPs/luminol composites release from the electrode surface to the solution, leading to significant reduction of the ECL signal. The change of the ECL intensity is related to the methylation status and MTase activity, which forms the basis of MTase activity assay and site-specific methylation determination. This novel strategy can be further used as a universal method for other transferase determination by designing various transferase-specific DNA sequences. In addition, this method can be used for the screening of antimicrobial drugs and has a great potential to be further applied in early clinical diagnosis.


Asunto(s)
Conductometría/instrumentación , Mediciones Luminiscentes/instrumentación , Luminol/química , Nanopartículas del Metal/química , Plata/química , Metiltransferasa de ADN de Sitio Específico (Adenina Especifica)/análisis , Técnicas Biosensibles/instrumentación , Activación Enzimática , Diseño de Equipo , Análisis de Falla de Equipo , Grafito/química , Nanopartículas del Metal/ultraestructura , Nanocompuestos/química , Nanocompuestos/ultraestructura , Óxidos/química , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Metiltransferasa de ADN de Sitio Específico (Adenina Especifica)/química
14.
Anal Chim Acta ; 812: 33-40, 2014 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-24491761

RESUMEN

We presented a novel electrogenerated chemiluminescence (ECL) biosensor for monitoring the activity and inhibition of protein kinases based on signal amplification using enzyme-functionalized Au NPs nanoprobe. In this design, the biotin-DNA labeled glucose oxidase/Au NPs (GOx/Au NPs/DNA-biotin) nanoprobes, prepared by conjugating Au NPs with biotin-DNA and GOx, were bound to the biotinylated anti-phosphoserine labeled phosphorylated peptide modified electrode surface through a biotin-avidin interaction. The GOx assembled on the nanoprobe can catalyze glucose to generate H2O2 in the presence of O2 while the ECL reaction occurred in the luminol ECL biosensor. At a higher concentration of kinase, there are more nanoprobes on the electrode, which gives a higher amount of GOx at the electrode interface and thus higher electrocatalytic efficiency to the luminol ECL reaction. Therefore, the activity of protein kinases can be monitored by ECL with high sensitivity. Protein kinase A (PKA), an important enzyme in regulation of glycogen, sugar, and lipid metabolism in the human body, was used as a model to confirm the present proof-of-concept strategy. The as-proposed biosensor presents high sensitivity, low detection limit of 0.013 U mL(-1), wide linear range (from 0.02 to 40 U mL(-1)), and excellent stability. Moreover, this biosensor can also be used for quantitative analysis of kinase inhibition. On the basis of the inhibitor concentration dependent ECL signal, the half-maximal inhibition value IC50 of ellagic acid, a typical PKA inhibitor, was estimated, which is in agreement with those obtained using the conventional kinase assay. The simple and sensitive biosensor is promising in developing a high-through assay of in vitro kinase activity and inhibitor screening for clinic diagnostic and drug development.


Asunto(s)
Técnicas Biosensibles , Sondas Moleculares , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Quinasas/metabolismo , Luminiscencia , Espectrofotometría Ultravioleta
16.
Zhonghua Xue Ye Xue Za Zhi ; 34(1): 55-9, 2013 Jan.
Artículo en Chino | MEDLINE | ID: mdl-23597467

RESUMEN

OBJECTIVE: To detect the changes of naive T cell level of thymic recent output at different stages of treatment in patients with diffuse large B-cell lymphoma (DLBCL), thereby to evaluate the relationship of thymic recent output function with prognosis and the impact of chemotherapy on the potential of immunological recovery. METHODS: The levels of T-cell receptor rearrangement excision circles (TREC) in DNA of peripheral blood mononuclear cells (PBMNC) from 30 DLBCL patients were monitored before, during, until 3 months and 6 months after chemotherapy by real-time PCR (TaqMan), and TREC-level was detected according to the number of CD3 positive(CD3(+)) cells. Twelve normal individuals who matched in age were served as controls. RESULTS: There was a dramatic reduction of TREC values in all DLBCL patients among which TREC values in germinal center B-cell-like-DLBCL (GCB-DLBCL) were higher than those in non-GCB-DLBCL, as compared with TREC values of normal individual in peripheral blood. The mean values of TREC were 0.91 ± 0.15/1000 PBMNCs and (1.22 ± 0.69)/1000 CD3(+) cells in GCB-DLBCL, (0.43 ± 0.29)/1000 PBMNCs and (0.64 ± 0.44)/1000 CD3(+) cells in non-GCB-DLBCL before chemotherapy. TREC values were significantly associated with lower international prognostic index (IPI) grade (r = -0.441, P = 0.015). TREC-level in DLBCL patients was further decreased after chemotherapy, and reached to the lowest level after the 6th cycle of chemotherapy, and during the corresponding period, the mean values of TREC were (0.63 ± 0.34)/1000 PBMNCs and (0.89 ± 0.65)/1000 CD3(+)cells in GCB-DLBCL, (0.19 ± 0.11)/1000 PBMNCs and (0.27 ± 0.25)/1000 CD3(+) cells in non-GCB-DLBCL. TREC-level began to rise obviously 3 months after the last cycle of chemotherapy in most of the DLBCL patients, and came close to normal level in five cases of patients 6 months after the last cycle of chemotherapy. CONCLUSIONS: Thymic recent output function was impaired severely in DLBCL patients. There was an important relationship between thymic recent output function before chemotherapy and prognosis, and chemotherapy had influenced the potential of immunological recovery.


Asunto(s)
Linfoma de Células B Grandes Difuso/inmunología , Receptores de Antígenos de Linfocitos T/inmunología , Timo/inmunología , Adulto , Anciano , Estudios de Casos y Controles , Femenino , Reordenamiento Génico de Linfocito T , Centro Germinal/inmunología , Humanos , Linfoma de Células B Grandes Difuso/tratamiento farmacológico , Linfoma de Células B Grandes Difuso/patología , Masculino , Persona de Mediana Edad , Adulto Joven
17.
Physiol Plant ; 148(3): 408-21, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23082802

RESUMEN

Transcriptionally active chromosome (TAC) is a fraction of protein/DNA complexes with RNA polymerase activity in the plastid. However, the function of most TAC proteins remains unknown. Here, we isolated two allelic mutants of the gene for a TAC component, TAC7, and performed functional analysis in plastid gene expression and chloroplast development in Arabidopsis. tac7-1 is a mutant with a premature translation termination isolated from a population treated with ethyl methane sulfonate, and tac7-2 is a transfer-DNA tagging mutant. Both of them showed an albino phenotype when grown under normal light conditions, and a few appressed membranes were observed inside the defective chloroplasts. These data indicate that TAC7 is important for thylakoid biogenesis. The TAC7 gene encodes an uncharacterized 161 amino acids polypeptide localized in chloroplast. The transcriptional levels of plastid-encoded polymerase (PEP)-dependent genes were downregulated in tac7-2, suggesting that PEP activity was decreased in the mutant. Yeast two-hybrid assay shows that TAC7 can interact with the four TAC components including FLN1, TAC10, TAC12 and TAC14 which are involved in redox state changes, phosphorylation processes and phytochrome-dependent light signaling, respectively, These data indicate that TAC7 plays an important role for TAC to regulate PEP-dependent chloroplast gene expression and chloroplast development.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , Cloroplastos/genética , Cromosomas de las Plantas/metabolismo , Regulación de la Expresión Génica de las Plantas , Secuencia de Aminoácidos , Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/genética , Secuencia de Bases , Núcleo Celular/metabolismo , Cloroplastos/ultraestructura , Genes de Plantas/genética , Prueba de Complementación Genética , Datos de Secuencia Molecular , Mutación/genética , Fenotipo , Filogenia , Unión Proteica , Transporte de Proteínas , Fracciones Subcelulares/metabolismo , Tilacoides/metabolismo , Tilacoides/ultraestructura
20.
Biochimie ; 88(7): 913-22, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16580116

RESUMEN

Lysosomal disintegration may cause apoptosis, necrosis and some diseases. However, mechanisms for these events are still unclear. In this study, we measured lysosomal beta-hexosaminidase free activity, membrane potential and intralysosomal pH. The results revealed that the cytosolic extracts of rat hepatocytes could increase the lysosomal permeability to both potassium ions and protons, and osmotically destabilize lysosomes via K(+)/H(+) exchange. The effects of cytosol on lysosomes could be completely abolished by D609, which inhibited both phospholipase C and sphingomyelinase, and partly prevented by sphingomyelinase inhibitor Ara-AMP, but not by the inhibitors of PLA(2). Moreover, purified phospholipase C could destabilize the lysosomes while phospholipase A(2) and phospholipase D did not produce such effects. The cytosolic phospholipases hydrolyzed lysosomal membrane phospholipids by 50%, which could be prevented by D609. Disintegration of the cytosol-treated lysosomes biphasically depended on the cytosolic [Ca(2+)]. The cytosol did not disintegrate lysosomes below 100 nM or above 10 muM cytosolic [Ca(2+)], but markedly destabilized lysosomes at about 340 nM [Ca(2+)]. The results suggest that cytosolic phospholipase C and sphingomyelinase may be responsible for the alterations in lysosomal stability by increasing the ion permeability.


Asunto(s)
Lisosomas/metabolismo , Esfingomielina Fosfodiesterasa/metabolismo , Fosfolipasas de Tipo C/metabolismo , Animales , Hidrocarburos Aromáticos con Puentes/farmacología , Calcio/metabolismo , Calcio/farmacología , Citosol/química , Citosol/enzimología , Citosol/metabolismo , Concentración de Iones de Hidrógeno , Hígado/citología , Hígado/metabolismo , Lisosomas/efectos de los fármacos , Norbornanos , Permeabilidad/efectos de los fármacos , Inhibidores de Fosfodiesterasa/farmacología , Fosfolípidos/metabolismo , Fosforilcolina/metabolismo , Potasio/metabolismo , Potasio/farmacología , Protones , Ratas , Esfingomielina Fosfodiesterasa/antagonistas & inhibidores , Tiocarbamatos , Tionas/farmacología , Fosfolipasas de Tipo C/antagonistas & inhibidores , beta-N-Acetilhexosaminidasas/metabolismo
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