RESUMO
The pearl oyster, Pinctada fucata, is cultured for pearl production in Japan. The shell of the pearl oyster consists of calcium carbonate and a small amount of organic matrix. Despite many studies of the shell matrix proteins, the mechanism by which calcium elements are transported from the mantle to the shell remains unclear. Investigating the molecular mechanism of calcium transportation, we prepared artificial seawater with a high concentration of calcium ions (10ASW) to induce calcification in the pearl oyster. When pearl oysters were cultured in 10ASW, unusual nanoparticles were precipitated on the surface of the nacreous layer. SDS-PAGE and 2D-PAGE analyses revealed that some calcium-sensing proteins (Sarcoplasmic Ca-binding Protein (Pf-SCP) and Pf-filamin A) might be related to the synthesis of these nanoparticles. The recombinant proteins of Pf-SCP can bind to calcium ions and accumulate nanoparticles of calcium carbonate crystals. However, transcriptomic analysis of the pearl oysters grown in 10ASW showed that the matrix protein genes in the shell did not differ before and after treatment with 10ASW. These results suggest that, despite increasing calcium transportation to the shell, treatment with a high concentration of calcium ions does not induce formation of the organic framework in the shell microstructure. These findings offer meaningful insights into the transportation of calcium elements from the mantle to the shell.
Assuntos
Pinctada/metabolismo , Sequência de Aminoácidos , Exoesqueleto , Animais , Cálcio/metabolismo , Carbonato de Cálcio/química , Carbonato de Cálcio/metabolismo , Filaminas/metabolismo , Perfilação da Expressão Gênica , Microscopia Eletroquímica de Varredura , Dados de Sequência MolecularRESUMO
Adoptive T-cell therapy is an effective strategy for cancer immunotherapy. However, infused T cells frequently become functionally exhausted, and consequently offer a poor prognosis after transplantation into patients. Adoptive transfer of tumor antigen-specific stem cell memory T (TSCM ) cells is expected to overcome this shortcoming as TSCM cells are close to naïve T cells, but are also highly proliferative, long-lived, and produce a large number of effector T cells in response to antigen stimulation. We previously reported that activated effector T cells can be converted into TSCM -like cells (iTSCM ) by coculturing with OP9 cells expressing Notch ligand, Delta-like 1 (OP9-hDLL1). Here we show the methodological parameters of human CD8+ iTSCM cell generation and their application to adoptive cancer immunotherapy. Regardless of the stimulation by anti-CD3/CD28 antibodies or by antigen-presenting cells, human iTSCM cells were more efficiently induced from central memory type T cells than from effector memory T cells. During the induction phase by coculture with OP9-hDLL1 cells, interleukin (IL)-7 and IL-15 (but not IL-2 or IL-21) could efficiently generate iTSCM cells. Epstein-Barr virus-specific iTSCM cells showed much stronger antitumor potentials than conventionally activated T cells in humanized Epstein-Barr virus transformed-tumor model mice. Thus, adoptive T-cell therapy with iTSCM offers a promising therapeutic strategy for cancer immunotherapy.
Assuntos
Imunoterapia Adotiva/métodos , Neoplasias , Células-Tronco/imunologia , Subpopulações de Linfócitos T/imunologia , Linfócitos T/imunologia , Animais , Linhagem Celular , Humanos , Memória Imunológica , Ativação Linfocitária/imunologia , Camundongos , Neoplasias/imunologiaRESUMO
Aluminium ions inhibit growth of the budding yeast Saccharomyces cerevisiae. Disruption of the SSO2 gene increased the susceptibility to aluminium. Sso2p belongs to the soluble N-ethylmaleimide sensitive factor attachment protein receptor (SNARE) family. SSO2 has one paralogue, SSO1, which encodes Sso1p. The SNARE complex containing Sso1/2p plays a role in the recognition of plasma membrane targeted vesicle transport. The susceptibility to aluminium stress was not increased in the Δsso1 strain. The phenotype of aluminium ion influx between the wild-type and Δsso2 strains was not different, suggesting that Sso2p was involved in the elimination of cellular aluminium. However, the cellular lipid constitution of Δsso2 was richer in unsaturated fatty acids than the wild type, indicating that Sso2p is associated with lipid homeostasis of the plasma membrane. Aluminium treatment increased the production of reactive oxygen species (ROS) during proliferation. ROS production was increased in the Δsso2 strain after 3 h of aluminium treatment compared with the wild type. These results suggested that Sso2p plays a role in maintaining the lipid composition of the plasma membrane and the increase in unsaturated fatty acids amplified the production of ROS in the acute phase of aluminium stress. ROS derived from aluminium stress inhibited growth and resulted in the susceptibility of the Δsso2 strain.
Assuntos
Alumínio/farmacologia , Proliferação de Células/efeitos dos fármacos , Proteínas Qa-SNARE/genética , Proteínas de Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/efeitos dos fármacos , Sequência de Aminoácidos/genética , Membrana Celular/efeitos dos fármacos , Membrana Celular/genética , Regulação Fúngica da Expressão Gênica/efeitos dos fármacos , Fusão de Membrana/efeitos dos fármacos , Fusão de Membrana/genética , Proteínas de Membrana/genética , Ligação Proteica/efeitos dos fármacos , Espécies Reativas de Oxigênio/química , Saccharomyces cerevisiae/crescimento & desenvolvimentoRESUMO
Most beetles belonging to the subfamily Carabinae of the family Carabidae (so-called carabid ground beetles) cannot fly, because their hind-wings are highly degenerated. However, about half of the species in the subtribe Calosomina within the same subfamily can fly. From extensive morphological examinations of the hind-wings of Carabinae species in conjunction with DNA molecular phylogenetic trees, the process and possible causes of hind-wing degeneration in the Carabinae are discussed.
Assuntos
Besouros/anatomia & histologia , Asas de Animais/anatomia & histologia , Animais , Evolução Biológica , Besouros/genética , DNA Mitocondrial/genética , Geografia , Filogenia , Especificidade da EspécieRESUMO
Asparagine-linked glycosylation (N-glycosylation) is necessary for the proper folding of secreted and membrane proteins, including GPCRs. Thus, many GPCRs possess the N-glycosylation motif Asn-X-Ser/Thr at their N-termini and/or extracellular loops. We found that human GPR109A (hGPR109A) has an N-glycosylation site at Asn(17) in the N-terminal atypical motif, Asn(17)-Cys(18)-Cys(19). Why does hGPR109A require the atypical motif, rather than the typical sequence? Here we show that Asn(17)-Cys(18)-Cys(19) sequence of hGPR109A possesses 2 biologic roles. First, Asn(17)-X-Cys(19) contributed to hGPR109A N-glycosylation by acting as an atypical motif. This modification is required for the normal surface expression of hGPR109A, as evidenced by the reduced surface expression of the nonglycosylated mutants, hGPR109A/N17A, and the finding that hGPR109A/C19S and hGPR109A/C19T, which are N-glycosylated at Asn(17), exhibited expression similar to the wild-type receptor. Second, the X-Cys(18)-Cys(19) dicysteine is indispensable for hGPR109A function. Substitution of Cys(18) or Cys(19) residue to Ala impaired Gi-mediated signaling via hGPR109A. We propose the disulfide bond formations of these residues with other Cys existed in the extracellular loops for the proper folding. Together, these results suggest that the atypical motif Asn(17)-Cys(18)-Cys(19) is crucial for the normal surface trafficking and function of hGPR109A.
Assuntos
Motivos de Aminoácidos/genética , Membrana Celular/metabolismo , Expressão Gênica , Receptores Acoplados a Proteínas G/genética , Receptores Nicotínicos/genética , Transdução de Sinais/genética , Sequência de Aminoácidos , Animais , Asparagina/genética , Asparagina/metabolismo , Western Blotting , Células CHO , Linhagem Celular Tumoral , Cricetinae , Cricetulus , Dipeptídeos/genética , Dipeptídeos/metabolismo , Glicosilação , Células HEK293 , Células HeLa , Hexosiltransferases/genética , Hexosiltransferases/metabolismo , Humanos , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Dados de Sequência Molecular , Mutação de Sentido Incorreto , Interferência de RNA , Receptores Acoplados a Proteínas G/metabolismo , Receptores Nicotínicos/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Homologia de Sequência de AminoácidosRESUMO
Medicines are distributed to the whole body and excreted over time. A micromodel of the circulation-excretion system was developed to mimic these processes. This system comprised a dialysis part, a microperistaltic pump, and a target tissue. This microcirculation system was created on a microchip composed of a glass slide and polydimethylsiloxane sheets with microchannels fabricated by photolithography. A dialysis membrane was settled between two channels to form the dialysis part, and a pneumatic peristaltic pump was used to make the solution flow. The excretion and half-life of solute substances absorbed to albumin were changed according to their affinity to the protein. MCF-7 human breast cancer cells were cultured as target cells for drug samples, and the activities of anticancer agents were assayed using our system. Our data demonstrated that the anticancer activity of docetaxel or thio-TEPA could be assayed on the microcirculation-excretion chip. This system may allow for reduced consumption of cells and reagents compared to those required for conventional in vitro bioassay systems.
Assuntos
Antineoplásicos/metabolismo , Eletroforese em Microchip/métodos , Microcirculação , Antineoplásicos/farmacologia , Técnicas de Cultura de Células , Linhagem Celular Tumoral , Diálise/instrumentação , Diálise/métodos , Eletroforese em Microchip/instrumentação , Humanos , Células MCF-7RESUMO
Although secondhand cigarette smoke is known to cause various health consequences, even the short-term effects of exposure to secondhand heated-tobacco-product (HTP) aerosol are unknown. The purpose of this study was to examine short-term symptoms related to secondhand HTP aerosol exposure. An internet-based self-reported questionnaire survey was conducted in 2019 as a part of the Japan Society and New Tobacco Internet Survey (JASTIS) study. In total, 8784 eligible respondents aged 15-73 years were analyzed. We examined the frequency (%) of secondhand combustible cigarette smoke and HTP aerosol exposure, and the exposure-related subjective symptoms (sore throat, cough, asthma attack, chest pain, eye pain, nausea, headache, and other symptoms). Overall, 56.8% of those exposed to secondhand cigarette smoke had any subjective symptoms, compared to 39.5% of those exposed to HTP aerosol. Asthma attack and chest pain were reported more frequently when associated with secondhand HTP exposure (10.9 and 11.8%, respectively) than with secondhand cigarette smoke exposure (8.4 and 9.9%, respectively). Sore throat, cough, eye pain, nausea, and headache were also more frequently reported when associated with secondhand cigarette smoke than with secondhand HTP exposure. This is the first study to examine severe subjective symptoms such as asthma attacks and chest pains, and to suggest that respiratory and cardiovascular abnormalities could be related to secondhand heated-tobacco-product aerosol exposure. Further careful investigations are necessary.
Assuntos
Asma , Produtos do Tabaco , Poluição por Fumaça de Tabaco , Adolescente , Adulto , Aerossóis/análise , Idoso , Dor no Peito , Humanos , Incidência , Internet , Japão/epidemiologia , Pessoa de Meia-Idade , Inquéritos e Questionários , Nicotiana , Poluição por Fumaça de Tabaco/efeitos adversos , Adulto JovemRESUMO
Oral medicines and food constituents are absorbed in the intestine and metabolized in the liver, after which they exhibit their activity toward a target tissue. Micromodels of human tissues were developed to mimic these processes and bioactivities. By integrating the micromodels, we realized a micro total bioassay system for oral substances; this system comprised a microintestine, microliver, and the target components. The microchip was composed of a slide glass and polydimethylsiloxane (PDMS) sheets with microchannels fabricated by photolithography. Caco-2 cells were cultured in the intestine component, and HepG2 cells, in the liver component. The human breast carcinoma MCF-7 cells were cultured in the target component, and the activities of anticancer agents and estrogen-like substances were successfully assayed. By using this system, the overall properties of the ingested cyclophosphamide, epirubicin, 17-ß estradiol, and soy isoflavone, i.e., their intestinal absorption, hepatic metabolism, and bioactivity toward target cells, could be assayed with operative ease. Further, the assay time and cell consumption were reduced compared to those in conventional in vitro bioassay systems.
Assuntos
Absorção Intestinal , Fígado/metabolismo , Procedimentos Analíticos em Microchip/métodos , Modelos Biológicos , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Ciclofosfamida/farmacologia , Epirubicina/farmacologia , Estradiol/farmacologia , Humanos , Isoflavonas/farmacologia , Dispositivos Lab-On-A-ChipRESUMO
Regulatory T cells (Tregs) play essential roles in maintaining immunological self-tolerance and preventing autoimmunity. The adoptive transfer of antigen-specific Tregs has been expected to be a potent therapeutic method for autoimmune diseases, severe allergy, and rejection in organ transplantation. However, effective Treg therapy has not yet been established because of the difficulty in preparing a limited number of antigen-specific Tregs. Chimeric antigen receptor (CAR) T cells have been shown to be a powerful therapeutic method for treating B cell lymphomas, but application of CAR to Treg-mediated therapy has not yet been established. Here, we generated CD19-targeted CAR (CD19-CAR) Tregs from human PBMCs (hPBMCs) and optimized the fraction of the Treg source as CD4+CD25+CD127loCD45RA+CD45RO-. CD19-CAR Tregs could be expanded in vitro while maintaining Treg properties, including high expression of the latent form of TGF-ß. CD19-CAR Tregs suppressed IgG antibody production and differentiation of B cells via a TGF-ß-dependent mechanism. Unlike conventional CD19-CAR CD8+ T cells, CD19-CAR Tregs suppressed antibody production in immunodeficient mice that were reconstituted with hPBMCs, reducing the risk of graft-versus-host disease. Therefore, the adoptive transfer of CD19-CAR Tregs may provide a novel therapeutic method for treating autoantibody-mediated autoimmune diseases.
Assuntos
Antígenos CD19/imunologia , Linfoma de Células B/terapia , Receptores de Antígenos Quiméricos/imunologia , Linfócitos T Reguladores/imunologia , Transferência Adotiva/métodos , Animais , Antígenos CD19/efeitos adversos , Antígenos CD19/genética , Antígenos CD19/farmacologia , Autoimunidade/genética , Autoimunidade/imunologia , Linfócitos B/imunologia , Linfócitos B/patologia , Epitopos , Doença Enxerto-Hospedeiro/etiologia , Doença Enxerto-Hospedeiro/imunologia , Doença Enxerto-Hospedeiro/prevenção & controle , Humanos , Tolerância Imunológica/genética , Imunoglobulina G/imunologia , Linfoma de Células B/complicações , Linfoma de Células B/genética , Linfoma de Células B/imunologia , Camundongos , Receptores de Antígenos Quiméricos/genética , Receptores de Antígenos Quiméricos/uso terapêutico , Linfócitos T Reguladores/patologia , Fator de Crescimento Transformador beta/genéticaRESUMO
An amendment to this paper has been published and can be accessed via a link at the top of the paper.
RESUMO
Cd(II) is toxic to many species, including humans, because it inactivates a number of enzymes and induces cytopathic effects in the liver, kidney, and skeletal tissues in humans. Metallothionein and glutathione (GSH) play a major role in the protection against Cd(II)-induced toxicity in mammalian cells. In this study, a relatively simple method for detecting trace amounts of Cd(II) chelators was developed by using 5,10,15,20-tetraphenyl-21H,23H-porphinetetrasulfonic acid (TPPS). The TPPS-Cd(II) complex was added to the elutions of high-performance liquid chromatography. The Cd(II) chelators separated by column chromatography were mixed with Cd(II)-bound TPPS (TPPS-Cd(II)). Cd(II) from TPPS-Cd(II) was chelated by the eluted Cd(II) chelators, resulting in the formation of free TPPS. The absorbance of TPPS shifted from 434 nm (TPPS-Cd(II)) to 414 nm (TPPS), and this characteristic shift was used to estimate the quantity and affinity of the Cd(II) chelators. This new method was compared with the bathocuproine disulfonate (BCS) method developed in our previous study. Instead of BCS-Cu(I), TPPS-Cd(II) was used as the colorimetric reagent. The experimental setup of the TPPS-based method is more general, and the preparation of the colorimetric solution is also much simpler than the BCS method. To verify the efficacy of this new method, we determined the actual Cd(II)-chelating ability of GSH in horse blood; the obtained concentration was in good agreement with the previously reported value.
Assuntos
Aporfinas/química , Cádmio/química , Quelantes/análise , Quelantes/química , Cromatografia Líquida de Alta Pressão/métodos , Animais , Glutationa , Cavalos , Limite de Detecção , Estresse OxidativoRESUMO
Adoptive T cell therapy is an attractive strategy in tumor immunotherapy. The transfer of in vitro expanded tumor-associated antigen (TAA)-specific T cells from patients may effectively destroy the original tumor cells. One of the limitations is a rapid acquisition of tolerant (anergy, deletion, dysfunctional, and/or exhausted) phenotypes. We and others found that stem cell memory T (TSCM) cells are strongly resistant to tolerance, showing strong expansion and persistence in vivo and providing long-lasting antitumor effects. We previously established that phenotypically TSCM cells (iTSCM) can be induced using a simple coculture of activated T cells with OP9 stroma cells expressing a Notch ligand. Here, we describe a defined protocol for generating human iTSCM cells, including reagents, culture setting, and procedure.
Assuntos
Linfócitos T CD8-Positivos/imunologia , Separação Celular/métodos , Citometria de Fluxo/métodos , Cultura Primária de Células/métodos , Animais , Antígenos de Neoplasias/imunologia , Proteínas de Ligação ao Cálcio/genética , Proteínas de Ligação ao Cálcio/metabolismo , Linhagem Celular Tumoral , Clonagem Molecular/métodos , Técnicas de Cocultura/instrumentação , Técnicas de Cocultura/métodos , Citometria de Fluxo/instrumentação , Técnica Direta de Fluorescência para Anticorpo , Voluntários Saudáveis , Humanos , Memória Imunológica , Imunoterapia Adotiva/métodos , Ativação Linfocitária , Masculino , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Células-Tronco Mesenquimais , Camundongos , Neoplasias/imunologia , Neoplasias/terapia , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Transdução Genética/métodosRESUMO
Gastrointestinal prokinetic agents function as serotonin-4 receptor (5-HT4R) agonists to activate myenteric plexus neurons to release acetylcholine (ACh), which then induce anti-inflammatory action. Details of this pathway, however, remain unknown. The aim of this study is to clarify the anti-inflammatory mechanism underlying the 5-HT4R agonist, mosapride citrate (MOS)-induced anti-inflammatory action on postoperative ileus (POI). POI models were generated from wild-type C57BL6/J (WT), 5-HT4R knock-out (S4R KO), α7 nicotinic AChR KO (α7 R KO), and M2 muscarinic ACh receptor KO (M2R KO) mice. MOS attenuated leukocyte infiltration in WT. MOS-induced anti-inflammatory action was completely abolished in both S4R KO and S4R KO mice upon wild-type bone marrow transplantation. MOS-induced anti-inflammatory action against macrophage infiltration, but not neutrophil infiltration, was attenuated in α7 R KO mice. Selective α7nAChR agonists (PNU-282987 and AR-R17779) also inhibited only macrophage infiltration in POI. MOS-mediated inhibition of neutrophil infiltration was diminished by atropine, M2AChR antagonist, methoctramine, and in M2R KO mice. Stimulation with 5-HT4R inhibits leukocyte infiltration in POI, possibly through myenteric plexus activation. Released ACh inhibited macrophage and neutrophil infiltration likely by activation of α7nAChR on macrophages and M2AChR. Thus, macrophage and neutrophil recruitment into inflamed sites is regulated by different types of AChR in the small intestine.
Assuntos
Anti-Inflamatórios/farmacologia , Intestino Delgado/efeitos dos fármacos , Receptores Colinérgicos/metabolismo , Acetilcolina/metabolismo , Animais , Anti-Inflamatórios/uso terapêutico , Benzamidas/farmacologia , Benzamidas/uso terapêutico , Compostos Bicíclicos com Pontes/farmacologia , Hidrocarbonetos Aromáticos com Pontes/farmacologia , Diaminas/farmacologia , Íleus/tratamento farmacológico , Íleus/patologia , Intestino Delgado/metabolismo , Leucócitos/citologia , Leucócitos/imunologia , Leucócitos/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Morfolinas/farmacologia , Morfolinas/uso terapêutico , Receptores Colinérgicos/química , Receptores Colinérgicos/genética , Receptores 5-HT4 de Serotonina/química , Receptores 5-HT4 de Serotonina/genética , Receptores 5-HT4 de Serotonina/metabolismo , Compostos de Espiro/farmacologia , Receptor Nicotínico de Acetilcolina alfa7/agonistas , Receptor Nicotínico de Acetilcolina alfa7/genética , Receptor Nicotínico de Acetilcolina alfa7/metabolismoRESUMO
Iron is an essential element for higher plants, and its acquisition and transportation is one of the greatest limiting factors for plant growth because of its low solubility in normal soil pHs. Higher plants biosynthesize ferric iron [Fe(III)] chelator (FIC), which solubilizes the iron and transports it to the rhizosphere. A high-performance liquid chromatography (HPLC) post-column method has been developed for the analysis of FICs using the luminol/H2O2 system for chemiluminescence (CL) detection. A size-exclusion column was the most suited in terms of column efficiency and CL detection efficiency. Mixing of the luminol with H2O2 in a post-column reaction was feasible, and a two-pump system was used to separately deliver the luminol and H2O2 solutions. The luminol and H2O2 concentrations were optimized using Fe(III)-EDTA and Fe(III)-citrate (Cit) solutions as analytes. A strong CL intensity was obtained for Fe(III)-Cit when EDTA was added to the luminol solution, probably because of an exchange of Cit with EDTA after separation on the HPLC column; CL efficiency was much higher for Fe(III)-EDTA than for Fe(III)-Cit with the luminol/H2O2 system. The present method can detect minute levels of Fe(III)-FICs; the detection limits of Fe(III)-EDTA, Fe(III)-Cit and Fe(III)-nicotianamine were 0.77, 2.3 and 1.1pmol, respectively.
Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Compostos Férricos/análise , Quelantes de Ferro/análise , Substâncias Luminescentes/química , Luminol/química , Ácido Azetidinocarboxílico/análogos & derivados , Ácido Azetidinocarboxílico/análise , Cromatografia Líquida de Alta Pressão/instrumentação , Ácido Cítrico/análise , Ácido Edético/análise , Desenho de Equipamento , Peróxido de Hidrogênio/químicaRESUMO
Gold nanoparticles have particular properties distinct from those of bulk gold crystals, and such nanoparticles are used in various applications in optics, catalysis, and drug delivery. Many reports on microbial synthesis of gold nanoparticles have appeared. However, the molecular details (reduction and dispersion) of such synthesis remain unclear. In the present study, we studied gold nanoparticle synthesis by Lactobacillus casei. A comparison of L. casei components before and after addition of an auric acid solution showed that the level of unsaturated lipids decreased significantly after addition. NMR and mass spectrum analysis showed that the levels of diglycosyldiacylglycerol (DGDG) and triglycosyldiacylglycerol (TGDG) bearing unsaturated fatty acids were much reduced after formation of gold nanoparticles. DGDG purified from L. casei induced the synthesis of gold nanoparticles in vitro. These results suggested that glycolipids, such as DGDG, play important roles in reducing Au(III) to Au(0) and in ensuring that the nanoparticles synthesized remain small in size. Our work will lead to the development of novel, efficient methods by which gold nanoparticles may be produced by, and accumulated within, microorganisms.
Assuntos
Galactolipídeos/química , Ouro/química , Lacticaseibacillus casei/química , Nanopartículas Metálicas/químicaRESUMO
CdSe quantum dots are often used in industry as fluorescent materials. In this study, CdSe quantum dots were synthesized using Fusarium oxysporum. The cadmium and selenium concentration, pH, and temperature for the culture of F. oxysporum (Fusarium oxysporum) were optimized for the synthesis, and the CdSe quantum dots obtained from the mycelial cells of F. oxysporum were observed by transmission electron microscopy. Ultra-thin sections of F. oxysporum showed that the CdSe quantum dots were precipitated in the intracellular space, indicating that cadmium and selenium ions were incorporated into the cell and that the quantum dots were synthesized with intracellular metabolites. To reveal differences in F. oxysporum metabolism, cell extracts of F. oxysporum, before and after CdSe synthesis, were compared using sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The results suggested that the amount of superoxide dismutase (SOD) decreased after CdSe synthesis. Fluorescence microscopy revealed that cytoplasmic superoxide increased significantly after CdSe synthesis. The accumulation of superoxide may increase the expression of various metabolites that play a role in reducing Se4+ to Se2- and inhibit the aggregation of CdSe to make nanoparticles.
RESUMO
We deduced the phylogenetic relationships of 54 individuals representing 27 species of the Calosomina (Coleoptera, Carabidae) from various regions of the world from the mitochondrial NADH dehydrogenase subunit 5 (ND 5) gene sequences. The results suggest that these Calosomina radiated into 17 lineages within a short time about 30 million years ago (Mya). Most of the lineages are composed of a single genus containing only one or a few species. In some cases, several species classified into the same genus (e.g., Calosoma maximowiczi, Calos. inquisitor and Calos. frigidum) appear separately in independent lineages, while in others a series of species classified into different genera fall into one lineage (e.g., Chrysostigma calidum, Blaptosoma chihuahua, Microcallisthenes wilkesi and Callisthenes spp.). Based on this molecular phylogeny and morphological data, the probable evolutionary history and mode of morphological differentiation of the Calosomina are discussed.
Assuntos
Besouros/genética , DNA Mitocondrial/genética , NADH Desidrogenase/genética , Filogenia , Animais , Besouros/anatomia & histologia , Evolução Molecular , Geografia , MasculinoRESUMO
Iron (Fe) is an essential element for higher plants, which take it up from the soil at the root surface and transport it to shoots through the xylem. Fe(III) chelators, such as organic acids and phytosiderophores, play important roles in the acquisition and transportation of Fe(III). Therefore, a selective and sensitive method for analyzing Fe(III) chelators is required to study the many Fe-related physiological mechanisms in plants. A novel analytical approach employing a high-performance liquid chromatography post-column method with fluorescence detection was developed to separate and detect Fe(III) chelators. This method takes advantage of the quenching of the fluorescence of Calcein Blue (CB) that occurs with the formation of an Fe(III)-CB complex and the dequenching that occurs with the release of CB as a result of competition for Fe(III) between CB and an Fe(III) chelator. This simple experimental method does not require complicated pretreatments and can selectively detect Fe(III) chelators according to their Fe(III)-chelating ability. The detection limit for citric acid using this method was 72pmol. Furthermore, this method can also detect unknown Fe(III) chelators that exhibit a high affinity for Fe(III). The method was evaluated with xylem sap of barley, which was shown to contain several Fe(III) chelators.
Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Fluoresceínas/análise , Quelantes de Ferro/análise , Fluoresceínas/metabolismo , Hordeum/química , Hordeum/metabolismo , Quelantes de Ferro/metabolismo , Limite de Detecção , Reprodutibilidade dos Testes , Xilema/químicaRESUMO
The phylogenetic position of the tribe Cychrini within the subfamily Carabinae (the family Carabidae) was estimated by comparing the nucleotide sequences of the mitochondrial NADH dehydrogenase subunit 5 (ND5) gene and the nuclear 28S ribosomal DNA (rDNA). The phylogenetic trees suggest that the Cychrini would most probably be the oldest line within the Carabinae. Phylogenetic trees were constructed by comparing the mitochondrial cytochrome C oxidase subunit I (COI) gene sequences from 33 species of the Cychrini from various localities that include the whole distribution ranges of the representative species within all the known genera in the world. The trees suggest that the Cychrini members radiated into a number of phylogenetic lineages within a short period, starting about 44 million years ago (MYA). Most of the phylogenetic lineages or sublineages are geographically linked, each consisting of a single or only a few species without scarce morphological differentiation in spite of their long evolutionary histories (silent or near-silent evolution [see Adv. Biophys. 36 (1999) 65; J. Mol. Evol. 53 (2001) 517]). The fact suggests that the geographic isolation per se did not bring about conspicuous morphological differentiation. The phylogenetic lineages of the Cychrini well correspond to the taxonomically defined genera and the subgenera.
Assuntos
Besouros/genética , DNA Mitocondrial/genética , Filogenia , Animais , Besouros/anatomia & histologia , Besouros/classificação , DNA Mitocondrial/química , Complexo IV da Cadeia de Transporte de Elétrons/genética , Variação Genética , Dados de Sequência Molecular , NADH Desidrogenase/genética , Subunidades Proteicas/genética , RNA Ribossômico 28S/genética , Análise de Sequência de DNARESUMO
Phylogenetic trees have been constructed using mitochondrial ND5 gene sequences of 85 specimens representing 40 species belonging to the division Lipastromorphi of the subtribe Carabina (= genus Carabus s. lat.) of the world. In the trees constructed by several methods, there have been recognized a basal split into two lineages, A and B, which are further divided into 2 (A1 and A2) and 9 (B1-B9) sublineages, respectively. Each sublineage and the clustering of the species in the trees are more or less linked to their geographic distribution. Morphology of the species within A1 or A2 in the lineage A is similar, and the species in most of the sublineages in the lineage B are common in a number of important morphological characters in spite of their long evolutionary histories. Whilst such a morphological stability, considerable morphological changes may be recognized upon or after split of lineages and sublineages. Based on the molecular phylogeny together with the morphological data, the pattern of diversification is discussed.