RESUMEN
The fungal bioluminescence pathway (FBP) is a metabolic pathway responsible for the generation of bioluminescence derived from fungi. This pathway utilizes caffeic acid as the substrate, generating a high-energy intermediate, and the decomposition of which yields green fluorescence with a wavelength of approximately 520 nm. The FBP is evolutionally conserved in luminescent fungal groups. Unlike other bioluminescent systems, the FBP is particularly suitable for engineering applications in eukaryotic organisms, especially in plants. Currently, metabolically engineered luminescent plants are able to emit visible light to illuminate its surroundings, which can be visualized clearly in the dark. The fungal bioluminescent system could be explored in various applications in molecular biology, biosensors and glowing ornamental plants, and even green lighting along city streets.
Asunto(s)
Luminiscencia , Luz , Fluorescencia , Eucariontes , Luz VerdeRESUMEN
The BTB (broad-complex, tramtrack, and bric-à-brac) domain is a highly conserved protein interaction motif in eukaryotes. They are widely involved in transcriptional regulation, protein degradation and other processes. Recently, an increasing number of studies have shown that these genes play important roles in plant growth and development, biotic and abiotic stress processes. Here, we summarize the advances of these proteins ubiquitination-mediated development and abiotic stress responses in plants based on the protein structure, which may facilitate the study of this type of gene in plants.
Asunto(s)
Eucariontes , Desarrollo de la Planta/genética , Proteolisis , UbiquitinaciónRESUMEN
Kummel's disease is a crush fracture of a vertebral body caused by a minor trauma, with the most accepted etiology being avascular necrosis. It is more frequent in individuals with risk factors such as osteoporosis or prolonged treatment with corticosteroids. Initially, it usually has normal radiological tests and an asymptomatic period, followed by a progressive onset of pain along with probable kyphosis and a sign of void or fluid abscess on radiological tests, which may create nerve/spinal involvement. The case is presented of a 76-year-old man, who was admitted to this center for the differential diagnosis of a single vertebral lesion. After imaging tests and biopsy, the definitive diagnosis of Kummel's disease was reached. The confirmatory diagnosis was reached by vertebral biopsy, but given its invasive nature, imaging techniques can play a significant role. As regards metabolic imaging tests, bone scintigraphy has shown to be one of the most sensitive tools to detect ischemia in earlier stages or to determine if it affects other locations. The whole body scan with diphosphonates shows an increase in activity in relation to bone remodeling activity in this condition. The 3-phase study makes it possible to differentiate whether it is an acute/subacute or chronic process, and can influence the therapeutic decision. Knowledge of this disease is important to make a differential diagnosis with tumour or infectious pathology, with emphasis on performing imaging tests in the event of persistent pain with a normal initial plaque.
La enfermedad de Kummel es una fractura-aplastamiento de un cuerpo vertebral precedida por un traumatismo menor, cuya etiología más aceptada es la necrosis avascular. Es más frecuente en individuos con factores de riesgo como osteoporosis o tratamiento prolongado con corticoides. Inicialmente, suele presentar pruebas radiológicas normales y un periodo asintomático, con aparición progresiva del dolor junto a probable cifosis y signo del vacío o absceso líquido en las pruebas radiológicas, pudiendo llegar a crear compromiso nervioso/medular. Presentamos el caso de un varón de 76 arios que ingresa en nuestro centro para el diagnóstico diferencial de una lesión única vertebral; tras la realización de las pruebas de imagen y biopsia se llega al diagnóstico definitivo de enfermedad de Kummel. El diagnóstico de confirmación de esta enfermedad se alcanza mediante la biopsia vertebral, pero dada su naturaleza invasiva, las técnicas de imagen toman un papel relevante. En relación con las pruebas de imagen metabólicas, la gammagrafía ósea ha demostrado ser una de las herramientas más sensibles para detectar isquemia en fases más tempranas o para conocer si afecta a otras localizaciones. El rastreo corporal de cuerpo completo con difosfonatos muestra un aumento de actividad en relación con la actividad ósea remodelativa en este cuadro. El estudio de tres fases permite diferenciar si se trata de un proceso agudo/subagudo o crónico, lo que influye en la decisión terapéutica. Es importante el conocimiento de esta enfermedad para realizar diagnóstico diferencial con patología tumoral o infecciosa e insistir en la realización de pruebas de imagen ante la persistencia del dolor con una placa inicial normal.
Asunto(s)
Humanos , Masculino , Anciano , Enfermedades Óseas , Cintigrafía , Enfermedades Musculoesqueléticas , Embryophyta , Técnicas y Procedimientos Diagnósticos , Carum , Diagnóstico , Eucariontes , Necrosis de la Cabeza FemoralRESUMEN
Os ribossomos são complexos ribonucleoproteicos conservados formados por duas subunidades assimétricas (40S e 60S em eucariotos) responsáveis pela tradução da informação genética e catálise da síntese proteica. A montagem destes complexos em eucariotos é mais bem descrita em S. cerevisiae, constituindo um processo celular energeticamente dispendioso e com múltiplas etapas. Ela tem origem no nucléolo com a transcrição do pré-rRNA 35S e requer o recrutamento hierárquico e transiente de cerca de 200 fatores de montagem para garantir a formação correta dos centros funcionais aptos à tradução. Neste processo, que se estende no núcleo e citoplasma, 79 proteínas ribossomais associam-se gradativamente à medida que o prérRNA é dobrado, modificado e processado. O processamento do pré-rRNA 35S consiste na remoção progressiva de espaçadores internos (ITS1 e ITS2) e externos (5ETS e 3ETS), que separam e flanqueiam os rRNAs maduros componentes de ambas subunidades ribossomais. A clivagem do ITS1 separa as vias de maturação do pré-60S e do pré-40S. O ITS2, que, em associação a fatores de montagem, forma uma estrutura denominada ITS2-foot, é o último espaçador do pré-60S a ser removido. A composição do ITS2-foot permanece inalterada no nucléolo até a transição entre o estado E nucleolar e a formação da partícula Nog2 nuclear. Nesta etapa, a liberação do fator Erb1 permite o recrutamento do fator de montagem conservado e essencial Nop53. Na base do ITS2-foot, Nop53 recruta o exossomo via RNA helicase Mtr4 para a clivagem 3-5 exonucleolítica de parte do ITS2 levando à desmontagem do ITS2-foot. O fato de Nop53 atuar como ponte entre dois grandes complexos e apresentar uma estrutura flexível e estendida nos levou a aprofundar a caracterização de seu papel durante a maturação do pré60S. Neste trabalho, usando análise proteômica quantitativa label-free baseada em espectrometria de massas, caracterizou-se o interactoma de Nop53, e avaliou-se o impacto da depleção de Nop53 no interactoma da subunidade catalítica do exossomo Rrp6 e na composição de pré-ribossomos representativos de quase todas as etapas de maturação do pré-60S. Em paralelo, foram caracterizados mutantes truncados de Nop53 e avaliada por pull-down a interação de Nop53 com componentes do exossomo. Os resultados obtidos mostraram que Nop53 é capaz de interagir com o cofator do exossomo Mpp6, sugerindo pontos adicionais de interação durante o recrutamento do exossomo ao pré-60S. A análise do interactoma de Rrp6 mostrou uma associação precoce do exossomo aos intermediários pré-ribossomais nucleolares mais iniciais, anteriores aos previamente descritos. Mudanças na composição dos intermediários pré-60S revelaram que a depleção de Nop53 afeta a transição entre o estado E e a partícula Nog2, afetando eventos tardios de maturação como o recrutamento de Yvh1. Comparando-se o efeito da depleção de Nop53 com o de mutantes nop53 desprovidos da região de recrutamento do exossomo, obtivemos evidências bioquímicas do papel estrutural de Nop53 na base do ITS2- foot. Em conjunto, estas observações, à luz de estruturas de intermediários pré-ribossomais recentemente descritas, nos permitiram concluir que o recrutamento de Nop53 ao pré-60S contribui para a estabilização de eventos de remodelamento do rRNA que antecedem a formação da partícula Nog2
Ribosomes are conserved ribonucleoprotein complexes formed by two asymmetric subunits (the 40S and the 60S in eukaryotes) responsible for translating the genetic information and catalyzing protein synthesis. The assembly of these complexes in eukaryotes is best described in S. cerevisiae. It is an energetically demanding, multi-step cellular process, that starts in the nucleolus with the transcription of the 35S pre-rRNA. It requires the hierarchical and transient recruitment of about 200 assembly factors to ensure the correct formation of the functional centers suitable for translation. In this process, which extends into the nucleus and cytoplasm, 79 ribosomal proteins gradually associate as the pre-rRNA is folded, modified, and processed. The 35S pre-rRNA processing happens with the progressive removal of internal (ITS1 and ITS2) and external (5'ETS and 3'ETS) transcribed spacers, which separate and flank the mature rRNA components of both ribosomal subunits. The cleavage at the ITS1 separates the pre-60S and pre40S maturation pathways. The ITS2, which in association with assembly factors constitutes a structure called ITS2-foot, is the last pre-60S spacer to be removed. The composition of the ITS2- foot remains unchanged in the nucleolus until the transition between the nucleolar state E and the nuclear Nog2 particle. At this stage, the release of Erb1 allows the recruitment of the conserved and essential assembly factor Nop53. At the base of the ITS2-foot, Nop53 recruits the exosome via the RNA helicase Mtr4 for the ITS2 3'-5' exonucleolytic cleavage leading to the ITS2-foot disassembly. The fact that Nop53 acts as a bridge between these two large complexes and exhibits a flexible and extended structure led us to further characterize its role in the pre-60S maturation. In this work, using mass spectrometry-based label-free quantitative proteomics, we characterized the interactome of Nop53, as well as the impact of the depletion of Nop53 on the interactome of the exosome catalytic subunit Rrp6 and on the composition of pre-ribosomes representative of almost all pre-60S maturation stages. In parallel, we characterized nop53 truncated mutants and evaluated the interaction of Nop53 with exosome components by pulldown assays. The results showed that Nop53 can interact with the exosome cofactor Mpp6, suggesting the contribution of additional points of interaction during the exosome recruitment to the pre-60S. The analysis of the Rrp6 interactome revealed an early association of the exosome with pre-ribosomal intermediates at very early nucleolar stages, before those previously described. Changes in the composition of pre-60S intermediates revealed that Nop53 depletion affects the transition between the state E and the Nog2 particle, affecting late pre-60S maturation events, such as the Yvh1 recruitment. Comparing the effect of Nop53 depletion with that of nop53 mutants lacking the exosome interacting region, we obtained biochemical evidence of the structural role of Nop53 at the base of the ITS2-foot. Altogether, and in light of recently described structures of pre-ribosomal intermediates, these observations allowed us to conclude that the recruitment of Nop53 to the pre-60S contributes to the stabilization of rRNA remodeling events that precede the formation of the Nog2 particle
Asunto(s)
Saccharomyces cerevisiae/clasificación , Subunidades Ribosómicas/química , Ribonucleoproteínas , Proteínas Ribosómicas , Espectrometría de Masas/métodos , Nucléolo Celular , Subunidades Ribosómicas Grandes , EucariontesRESUMEN
Group Ⅱ introns are self-splicing ribozymes, which insert directly into target sites in DNA with high frequency through "retrohoming". They specifically and efficiently recognize and splice DNA target sites, endowing themselves with great potential in genetic engineering. This paper reviewed the gene targeting principle of group Ⅱ introns and the application in microbial genetic modification, and then analyzed the limitations of them in multi-functional gene editing and eukaryotes based on the "retrohoming" characteristics and the dependence on high Mg2+ concentration. Finally, we dissected the potential of group Ⅱ introns in the development of novel gene editing tools based on our previous research outcome and the structural characteristics of the introns, hoping to provide a reference for the application of group Ⅱ introns in biotechnology.
Asunto(s)
ADN , Eucariontes , Marcación de Gen , Intrones/genética , ARN Catalítico/genéticaRESUMEN
WRKY is a superfamily of plant-specific transcription factors, playing a critical regulatory role in multiple biological processes such as plant growth and development, metabolism, and responses to biotic and abiotic stresses. Although WRKY genes have been characterized in a variety of higher plants, little is known about them in eukaryotic algae, which are close to higher plants in evolution. To fully characterize algal WRKY family members, we carried out multiple sequence alignment, phylogenetic analysis, and conserved domain prediction to identify the WRKY genes in the genomes of 30 algal species. A total of 24 WRKY members were identified in Chlorophyta, whereas no WRKY member was detected in Rhodophyta, Glaucophyta, or Bacillariophyta. The 24 WRKY members were classified into Ⅰ, Ⅱa, Ⅱb and R groups, with a conserved heptapeptide domain WRKYGQ(E/A/H/N)K and a zinc finger motif C-X4-5-C-X22-23-H-X-H. Haematococcus pluvialis, a high producer of natural astaxanthin, contained two WRKY members (HaeWRKY-1 and HaeWRKY-2). Furthermore, the coding sequences of HaeWRKY-1 and HaeWRKY-2 genes were cloned and then inserted into prokaryotic expression vector. The recombinant vectors were induced to express in Escherichia coli BL21(DE3) cells and the fusion proteins were purified by Ni-NTA affinity chromatography. HaeWRKY-1 had significantly higher expression level than HaeWRKY-2 in H. pluvialis cultured under normal conditions. High light stress significantly up-regulated the expression of HaeWRKY-1 while down-regulated that of HaeWRKY-2. The promoters of HaeWRKY genes contained multiple cis-elements responsive to light, ethylene, ABA, and stresses. Particularly, the promoter of HaeWRKY-2 contained no W-box specific for WRKY binding. However, the W-box was detected in the promoters of HaeWRKY-1 and the key enzyme genes HaeBKT (β-carotene ketolase) and HaePSY (phytoene synthase) responsible for astaxanthin biosynthesis. Considering these findings and the research progress in the related fields, we hypothesized that the low expression of HaeWRKY-2 under high light stress may lead to the up-regulation of HaeWRKY-1 expression. HaeWRKY-1 may then up-regulate the expression of the key genes (HaeBKT, HaePSY, etc.) for astaxanthin biosynthesis, consequently promoting astaxanthin enrichment in algal cells. The findings provide new insights into further analysis of the regulatory mechanism of astaxanthin biosynthesis and high light stress response of H. pluvialis.
Asunto(s)
Eucariontes , Regulación de la Expresión Génica de las Plantas , Filogenia , Proteínas de Plantas/metabolismo , Plantas/metabolismo , Estrés Fisiológico/genética , Factores de Transcripción/metabolismoRESUMEN
Objective: To investigate the effects of glycogen synthase kinase-3β (GSK3β)/eukaryotic extension factor kinase 2 (eEF2K) signaling pathway on the process of pulmonary fibrosis through in vivo experiments, and find new ideas for clinical treatment of pulmonary fibrosis. Methods: The pulmonary fibrosis model of C57BL/6 male mice was induced by bleomycin with intratracheal injection at the dose of 2 mg/kg. After 14 days of modeling, animals were divided into model group, negative inhibition group and inhibition group (n=5 for each group), and control group was not processed. The inhibition group was treated with TDZD-8 (4 mg/kg) after modeling, the negative inhibition group was given DMSO solution after modeling, and the samples were collected after 28 days. Hematoxylin-eosin staining method was used to detect lung fibrosis in mice and scored according to Ashcroft scale. Expression levels of GSK3β, p-GSK3β, eEF2K, p-eEF2K (Ser70, Ser392, Ser470), precursor protein of matrix metalloproteinase-2 (pro-MMP-2), matrix metalloproteinase-2 (MMP-2), collagen I (Col I), collagen Ⅲ (Col Ⅲ) and α-smooth muscle actin (α-SMA) were detected by Western blot. Results: Compared with control group, the fibrosis score was up-regulated, the expression levels of GSK3β, p-GSK3β, p-eEF2K (Ser70, Ser392, Ser470), pro-MMP-2, MMP-2, Col I, Col Ⅲ and α-SMA were increased, while that of eEF2K was decreased in model group (P<0.05). Compared with model group, the fibrosis score, expression levels of GSK3β, p-GSK3β, p-eEF2K (Ser70, Ser392, Ser470), pro-MMP-2, MMP-2, Col I, Col Ⅲ and α-SMA were decreased, but the expression level of eEF2K was increased in inhibition group (P<0.05). Conclusion: GSK3β can activate eEF2K by phosphorylation at the sites of Ser70, Ser392 and Ser470, increase the contents of fibrosis indicators, promote the formation of pulmonary fibrosis, and aggravate lung tissue lesions.
Asunto(s)
Animales , Masculino , Ratones , Colágeno , Colágeno Tipo I , Quinasa del Factor 2 de Elongación/metabolismo , Eucariontes/metabolismo , Fibrosis , Glucógeno Sintasa Quinasa 3 beta , Metaloproteinasa 2 de la Matriz/metabolismo , Ratones Endogámicos C57BL , Fibrosis Pulmonar/inducido químicamente , Transducción de SeñalRESUMEN
OBJECTIVE@#To conduct eukaryotic expression of the leucine-rich repeat containing 15 (LRRC15), a differentially expressed protein in excretory secretory antigens of Taenia solium cysticercus, and predict its antigen epitope.@*METHODS@#The molecular weight, stability, amino acid sequence composition, isoelectric point and T lymphocyte epitope of the LRRC15 protein were predicted using the bioinformatics online softwares ExPASy-PortParam and Protean. The full-length splicing primers were designed using PCR-based accurate synthesis, and the LRRC15 gene was synthesized. The recombinant pcDNA3.4-LRRC15 plasmid was constructed and transfected into HEK293 cells to express the LRRC15 protein. In addition, the LRRC15 protein was characterized by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) and Western blotting.@*RESULTS@#The recombinant pcDNA3.4-LRRC15 plasmid was successfully constructed, which expressed the target LRRC15 protein with an approximately molecular weight of 70 kDa. Bioinformatics prediction with the ExPASy-PortParam software showed that LRRC15 was a hydrophilic protein, which was consisted of 644 amino acids and had a molecular weight of 69.89 kDa and an isoelectric point of 5.6. The molecular formula of the LRRC15 protein was C3073H4942N846O953S28 and had an instability coefficient is 50.3, indicating that LRRC15 was an instable protein. Bioinformatics prediction with the Protean software showed that the dominant T-cell antigen epitopes were located in 292 to 295, 353 to 361, 521 to 526 and 555 to 564 amino acids of the LRRC15 protein, and the T-cell antigen epitopes with a high hydrophilicity, good flexibility, high surface accessibility and high antigenicity index were found in 122 to 131, 216 to 233, 249 to 254, 333 to 343, 358 to 361, 368 to 372, 384 to 386, 407 to 412, 445 to 450, 469 to 481, 553 to 564, 588 to 594, 607 to 617 and 624 to 639 amino acids. Following transfection of the recombinant pcDNA3.4-LRRC15 plasmid into HEK293 cells, SDS-PAGE and Western blotting identified LRRC15 proteins in cell secretory culture media, cell lysis supernatants and sediments. The LRRC15-His fusion protein was purified from the cell culture medium, and SDS-PAGE identified a remarkable band at approximately 70 kDa, while Western blotting successfully recognized the band of the recombinant LRRC15 protein.@*CONCLUSIONS@#The eukaryotic expression and antigen epitope prediction of the LRRC15 protein in the excretory secretory antigens of T. solium cysticercus have been successfully performed, which provides insights into further understandings of its biological functions.
Asunto(s)
Animales , Humanos , Aminoácidos , Antígenos Helmínticos/genética , Cysticercus/genética , Epítopos/genética , Eucariontes , Células HEK293 , Proteínas Repetidas Ricas en Leucina , Proteínas de la Membrana , Taenia solium/genéticaRESUMEN
Aims@#Thraustochytrids have been shown to be excellent lipid producers due to their ability to accumulate over 50% lipid (g/g biomass) containing up to 50% docosahexaenoic acid (DHA). However, efficient and cost-effective cell recovery of lipid-rich biomass has become a significant challenge at the industrial scale. In this study, we attempted to enhance the harvesting efficiency (HE) and the DHA content of Aurantiochytrium sp. through co-cultivation with a γ-linolenic acid (GLA)-producing oleaginous filamentous fungus, Cunninghamella bainieri 2A1.@*Methodology and results@#A 72 h old C. bainieri 2A1 culture in the form of loose mycelia or pellets of various sizes was added into 72 h old Aurantiochytrium sp. cultures and further incubated for 48 h. The HE of Aurantiochytrium sp. was then determined by comparing the remaining OD values of the supernatant with and without minimal centrifugation at 4000× g. Results showed that 63.23% of HE was achieved without centrifugation from co-cultivation with dispersed mycelia. Higher HE between 96.71-99.55% was achieved when centrifugation was implemented, with the highest value resulting from co-cultivation with dispersed mycelia. These are higher than HE of centrifuged control cultures (80%) consisting of Aurantiochytrium sp. monocultures, suggesting that co-cultivation with C. bainieri 2A1 facilitates the recovery of Aurantiochytrium sp. cells. Moreover, the co-cultivation also resulted in a 28% increase in DHA compared to non-optimized cultures.@*Conclusion, significance and impact of study@#This study provides the first evidence of enhancement in harvesting and DHA content of oleaginous thraustochytrids that could be achieved through co-cultivation with oleaginous fungi.
Asunto(s)
Procesos Heterotróficos , Cunninghamella , EucariontesRESUMEN
O glifosato é um herbicida amplamente utilizado. A Organização Mundial da Saúde (OMS) reclassificou o glifosato como "provavelmente cancerígeno a humanos". A remoção do glifosato do ambiente pode ser realizada por ação enzimática microbiana. O presente trabalho enfocou o isolamento de microrganismos do solo capazes de tolerar glifosato como única fonte de carbono. As células foram isoladas em meio de cultivo mínimo suplementado com glifosato. Foram isoladas 17 bactérias, 14 fungos e 1 levedura. Foi verificada a produção da biomassa microbiana na presença e na ausência do glifosato. Um fungo (F3) e uma levedura (L1) foram selecionados após teste de tolerância ao glifosato em meio líquido. Os microrganismos toleraram o glifosato, entretanto, o metabolismo foi afetado pelo herbicida, comparado ao controle sem glifosato. Estatisticamente, o tempo de crescimento apresentou diferenças significativas. Microrganismos eucarióticos isolados de solo com glifosato são tolerantes ao composto e podem ser úteis como biorremediadores de ambientes afetados por este herbicida.(AU)
Glyphosate is one of the most widely used herbicides. The World Health Organization (WHO) has reclassified glyphosate as "probably carcinogenic to humans". Glyphosate removal from the environment can be performed by microbial enzymatic action. The present work focused on the isolation of soil microorganisms that can tolerate glyphosate as the sole carbon source. Cells were isolated in minimal culture medium supplemented with glyphosate. Microbial biomass production was verified in the presence and absence of glyphosate. Seventeen, fourteen and one bacteria, fungi and yeast were isolated, respectively. One fungus (F3) and one yeast (L1), were selected after glyphosate tolerance test in liquid medium. Eukaryotic microorganisms tolerate glyphosate, however metabolism was affected by herbicide compared to control without glyphosate. Statistically growth time showed significant differences. Eukaryotic microorganisms isolated from soil with glyphosate are tolerant to the compound and may be useful as bioremediators of environments affected by this herbicide.(AU)
Asunto(s)
Animales , Eucariontes , Herbicidas , Suelo , BacteriasRESUMEN
BACKGROUND: BMPR-1B is part of the transforming growth factor ß super family and plays a pivotal role in ewe litter size. Functional loss of exon-8 mutations in the BMPR-1B gene (namely the FecB gene) can increase both the ewe ovulation rate and litter size. RESULTS: This study constructed a eukaryotic expression system, prepared a monoclonal antibody, and characterized BMPR-1B/FecB protein-protein interactions (PPIs). Using Co-immunoprecipitation coupled to mass spectrometry (Co-IP/MS), 23 proteins were identified that specifically interact with FecB in ovary extracts of ewes. Bioinformatics analysis of selected PPIs demonstrated that FecB associated with several other BMPs, primarily via signal transduction in the ovary. FecB and its associated interaction proteins enriched the reproduction process via BMP2 and BMP4 pathways. Signal transduction was identified via Smads proteins and TGF-beta signaling pathway by analyzing the biological processes and pathways. Moreover, other target proteins (GDF5, GDF9, RhoD, and HSP 10) that interact with FecB and that are related to ovulation and litter size in ewes were identified. CONCLUSIONS: In summary, this research identified a novel pathway and insight to explore the PPi network of BMPR-1B.
Asunto(s)
Animales , Femenino , Ovario/metabolismo , Receptores de Proteínas Morfogenéticas Óseas de Tipo 1/genética , Eucariontes/genética , Mapas de Interacción de Proteínas/genética , Espectrometría de Masas , Polimorfismo de Longitud del Fragmento de Restricción , Ovinos , Transducción de Señal , Reacción en Cadena de la Polimerasa , Biología Computacional , Receptores de Proteínas Morfogenéticas Óseas de Tipo 1/metabolismo , Eucariontes/metabolismo , Genotipo , MutaciónRESUMEN
OBJECTIVE@#To construct a eukaryotic expression vector of human tissue factor pathway inhibitor-2 (TFPI-2) and to investigate the effect of TFPI-2 gene on the growth of acute monocytic leukemia cell line (SHI-1).@*METHODS@#The cDNA of TFPI-2 was obtained by genetic chemical synthesis, the TFPI-2 gene and the linear vector fragment were ligated and inserted into the multiple cloning site of PEGFP-N1 vector, and the eukaryotic expression vector PEGFP-N1-TFPI-2 was transfected SHI-1 cells, then the obtained SHI-1 cells was observed by fluorescence microscopy; MTT assay was used to detect the effect of TFPI-2 gene on the relative growth rate of SHI-1 cells at the different time-point; RT-PCR was used to detect TFPI-2 mRNA expression levels in the cells of each group before and after TFPI-2 transfection; TFPI-2 protein expression was detected by Western blot. The cells which successfully transfected with PEGFP-N1-TFPI-2 vector were named as SHI-1-TFPI-2 (experimental group), and the cells transfected with the empty vector pEGFP-N1 and the untransfected cells were named as SHI-1-V and SHI-1-P and used as the control group.@*RESULTS@#The human TFPI-2 gene eukaryotic expression vector PEGFP-N1-TFPI-2 was successfully constructed, then the transfected into SHI-1 cells, observed by fluorescence microscopy 24 hours later, as a result, the PEGFP-N1-TFPI-2 was successfully transferred into SHI-1 cells, and the number of fluorescent cells increased after 48 h and 72 h. RT-PCR showed that the gray scale ratio of TFPI-2 gene to β- actin in the experimental group was higher than that in the control group. The gray scale ratio was 0.51±0.04 in SHI-1-V group, 0.52±0.03 in SHI-1-P group, 0.87±0.08 in SHI-1-TFPI-2 group, and the difference between SHI-1-TFPI-2 and SHI-1-V, SHI-1-P group was statistically significant (P<0.05).@*CONCLUSION@#The expression of TFPI-2 gene in PEGFP-N1-TFPI-2 can inhibit the growth of SHI-1 cells, which provides a research direction for gene therapy of leukemia in the future.
Asunto(s)
Humanos , Eucariontes , Vectores Genéticos , Glicoproteínas , Metabolismo , Proteínas Fluorescentes Verdes , TransfecciónRESUMEN
OBJECTIVE@#To construct eukaryotic expression vectors for human platelet CD36 gene 220 C>T and 429+4insg variants and analyze their expressions in HEK293T cells.@*METHODS@#RNA was isolated from human platelets and reversely transcribed into cDNA. Sequences of 220C>T and 429+4insg variants were derived by PCR amplification. The target sequence was ligated into a pcDNA3.1/V5-His-TOPO vector by TA cloning, which was transformed into TOP10 E. coli. Positive plasmids were screened by blue-white selection. After sequencing, plasmid DNA carrying 220C>T or 429+4insg variant was used to transfect HEK293T cells with the help of effectene. Expression of CD36 protein was then analyzed by flow cytometry and Western blotting.@*RESULTS@#An eukaryotic expression vector pcDNA3.1/V5-His-CD36 (220C>T/429+4insg) was constructed by TA cloning. After transfected into HEK293T cells, the 220C>T and 429+4insg variants resulted in CD36 deficiency in HEK cells, which was confirmed by flow cytometry and Western blotting.@*CONCLUSION@#The 220C>T and 429+4insg variants can cause CD36 deficiency in human platelets. This system may be used for assessing the effect of 220C>T, 429+4insg, and other variants on the expression of CD36.
Asunto(s)
Humanos , Plaquetas , Antígenos CD36 , Clonación Molecular , Escherichia coli , Eucariontes , Vectores Genéticos , Células HEK293 , Plásmidos , TransfecciónRESUMEN
O câncer cervical é um dos tipos de câncer mais comuns entre as mulheres, e a infecção persistente pelos HPV-16 e HPV-18 é responsável por 70% dos casos. As vacinas profiláticas disponíveis possuem alta eficácia na prevenção da infecção pelos tipos mais prevalentes de HPV. No entanto, este tipo de abordagem não beneficia mulheres que já apresentam lesões precursoras ou tumores cervicais avançados, e a busca por abordagens terapêuticas para esse tipo de câncer é considerada uma necessidade. A qualidade do antígeno representa um aspecto fundamental para o sucesso de vacinas terapêuticas baseadas em proteínas recombinantes. Neste sentido, os sistemas de expressão em células eucarióticas, como leveduras e células de mamíferos são considerados adequados para a produção de proteínas com aplicação biotecnológica. O objetivo principal deste trabalho contemplou a expressão das proteínas de fusão gDE7E6 do HPV-16 e do HPV-18 e a oncoproteína E7 do HPV-16 em células da levedura Pichia pastoris e expressão da gDE7E6 do HPV-16 e do HPV-18 em células de mamífero HEK293T e CHODG-44 para obtenção de antígenos purificados com futura aplicação em vacinas terapêuticas contra tumores associados ao HPV-16 e HPV-18. Os genes que codificam as proteínas gDE7E6 dos HPV-16 e HPV-18 e da E7 do HPV-16 foram clonados no vetor pPIC9K, os quais foram linearizados por digestão enzimática e utilizados na transformação da P. pastoris. A expressão das proteínas foi analisada nos tempos de 24, 48, 72 e 96 horas, no entanto, não foi observada a produção das proteínas no sobrenadante e nem no lisado celular. Diante desta constatação, iniciamos a expressão das proteínas gDE7E6 do HPV-16 e gDE7E6 do HPV-18 em células de mamíferos HEK293T e CHODG-44. As sequências genéticas das proteínas gDE7E6 do HPV-16 e do HPV-18 foram clonadas no vetor de expressão pNU1 e analisadas por digestão enzimática. Análises de SDS-PAGE e western blot demonstraram a expressão das proteínas gDE7E6 do HPV-16 e do HPV-18 em até 96 horas em células HEK293T. Em paralelo, realizamos a transfecção estável dos plasmídeos contendo as sequencias da gDE7E6 do HPV-16 e gDE7E6 do HPV-18 em células CHO-DG44. Com o intuito de aumentar a expressão das proteínas de interesse na população mista de CHODG-44, realizamos amplificação genômica com metotrexato (MTX), sendo possível observar aumento da expressão das proteínas, conforme aumento gradativo nas concentrações de MTX. Posteriormente, foram feitas tentativas para isolar um clone produtor das proteínas gDE7E6 HPV-16 e HPV-18, através de clonagem por diluição limitante e sistema automatizado, sendo possível isolar um clone para cada construção através de matriz semisólida, confirmado por western blot e citometria de fluxo. Apesar de demonstrar a expressão das proteínas de interesse em sistema de expressão baseado em células de mamífero, o rendimento obtido após a purificação por afinidade ao níquel foi extremamente baixo, o que dificulta a obtenção dos antígenos para fins vacinais
Cervical cancer is one of the most common cancers among women, and persistent infection with HPV-16 and HPV-18 accounts for 70% of the cases. Available prophylactic vaccines are highly effective in preventing infection by the most prevalent types of HPV. However, this type of approach does not benefit women who already have precursor lesions or advanced cervical tumors, and the search for therapeutic approaches to this type of cancer is considered a necessity. Antigen quality represents a key aspect for the success of therapeutic vaccines based on recombinant proteins. In this sense, expression systems based in eukaryotic cells such as yeast and mammalian cells are considered suitable for the production of proteins with biotechnological applications. The main objective of this work was to express the gDE7E6 fusion proteins HPV-16 and HPV-18 and the E7 oncoprotein HPV-16 in Pichia pastoris and expression of gDE7E6 HPV-16 and HPV-18 in mammalian cells HEK293T and CHODG-44 to obtain purified antigens with future applications in therapeutic vaccines against HPV-16 and HPV-18 associated tumors. The genes encoding the gDE7E6 proteins HPV-16 and HPV-18 and E7 HPV-16 were cloned into the pPIC9K vector, which were linearized by enzymatic digestion and used in the transformation of P. pastoris. Expression of the proteins was analyzed at 24, 48, 72 and 96 hours, however, the production of the proteins in the supernatant and in the cell lysate was not observed. In light of this finding, we initiated the expression of gDE7E6 proteins HPV-16 and HPV-18 in mammalian cells HEK293T and CHODG-44. The genetic sequences of gDE7E6 proteins HPV-16 and HPV-18 were cloned into the pNU1 expression vector and analyzed by enzymatic digestion. SDSPAGE and western blot analyzes demonstrated expression of gDE7E6 proteins HPV-16 and HPV-18 within 96 hours in HEK293T cells. In parallel, we performed stable transfection of plasmids containing gDE7E6 HPV-16 and HPV-18 sequences into CHODG44 cells. In order to increase the expression of the proteins in the mixed population of CHODG-44, we performed genomic amplification with methotrexate (MTX), and it was possible to observe an increase in protein expression, as a gradual increase in MTX concentrations. Therefore, attempts were made to isolate a clone producing gDE7E6 proteins HPV-16 and HPV-18 by limiting dilution and automated system, being possible to isolate one clone for each construct through a semisolid matrix, confirmed by western blot and flow cytometry. Despite observing protein expression in mammalian cell-based expression system, the yield obtained after nickel affinity purification was extremely low, which makes it difficult to obtain the antigens for vaccine purposes
Asunto(s)
Proteínas Oncogénicas/clasificación , Papillomavirus Humano 16 , Papillomavirus Humano 18 , Pichia , Neoplasias del Cuello Uterino/fisiopatología , Herpesvirus Humano 1 , Eucariontes , Antígenos/análisisRESUMEN
Relógios endógenos controlam grande parte de processos biológicos através de osciladores bioquímicos que coordenam a sinalização de pistas ambientais até vias metabólicas, permitindo a percepção do tempo e adaptação a mudanças rítmicas. Comportamentos cíclicos diários foram primordialmente descritos em plantas e, mais recentemente, têm fornecido informações valiosas sobre os ciclos de retroalimentação da transcrição e tradução de genes que controlam estes osciladores. O florescimento é um exemplo bem conhecido da importância da percepção do comprimento do dia através do relógio, processo intimamente regulado por fotorreceptores e pelos genes centrais e periféricos do relógio biológico. Em organismos multicelulares há uma combinação específica de genes mais expressa em cada tecido, podendo ter funções, fases e períodos diferentes, o que aumenta a complexidade desse mecanismo. Devido a isso, tem-se buscado modelos alternativos mais simples dentro dos eucariotos fotossintetizantes relacionados às plantas terrestres. Modelos simplificados facilitam, por exemplo, a avaliação da combinação de fatores que induzem o estresse e como o relógio biológico se altera, permitindo a antecipação de mudanças ambientais e sincronização da fisiologia com o meio ambiente. Neste trabalho, verificou-se como o relógio circadiano se ajusta ao estresse em 3 diferentes modelos: Gracilaria tenuistipitata (Rhodophyta), Ostreococcus tauri (Chlorophyta) e Saccharum sp (Embryophyta). Para isso, estabeleceu-se em G. tenuistipitata métodos para avaliação de crescimento e da fluorescência da clorofila de modo automático, comprovando da existência de ritmos circadianos. Além disso, após padronização de genes de referência para normalização das RT-qPCRs, o gene TRX ficou superexpresso durante a primeira hora após o déficit hídrico. Já em O. tauri, onde os genes centrais do relógio são conhecidos, mudanças na expressão de LOV-HK e TOC1 estão relacionadas com maior crescimento em baixa e alta temperatura, respectivamente. Uma combinação específica de luz, temperatura e salinidade pode ser um importante indutor de eflorescências que reflete mudanças transcricionais no oscilador central, o que pode ser comparado às florescências de plantas terrestres. Já em Saccharum sp tolerante à seca, ritmos de fotossíntese e de expressão de CCA1 sofrem mudanças de fase em suas oscilações e transcritos de HVA-22 e DRP são significativamente mais expressos sob dessecação. Em suma, o estresse em Saccharum sp reseta o relógio, aumentando o período de oscilação da fotossíntese. Em O. tauri induz maior crescimento, mantendo as características do relógio. Não foi possível avaliar o efeito do estresse no relógio de G. tenuistipitata, mas ferramentas foram desenvolvidas visando este objetivo. Estudos de respostas do relógio podem fornecer informações valiosas para o entendimento da reprodução e crescimento de organismos com elevado potencial de aplicações biotecnológicas
Endogenous clocks control a large range of biological processes through biochemical oscillators that coordinate the signaling of environmental cues to metabolic pathways, allowing the perception of time and adjust to rhythmic changes. Cyclical daily behaviors were first noticed in plants and, more recently, revealed information about the transcriptional-translational feedback loops of genes that control these oscillators. Flowering is a well-known process where the perception of day length by the clock is intimately regulated by photoreceptors and by the central and peripheric genes of the biological clock. Multicellular organisms have a tissue-specific combination of expressed clock genes that may have different phase and period, increasing the complexity of this mechanism. Due to this reason, alternative models have been proposed for land plants-related photosynthetic eukaryotes. New models can simplify, for example, which combination of factors induce stress and how the biological clock is altered, allowing the anticipation of environmental changes and synchronization of physiology and environmental factors. This work aimed to verify how the biological clock adjusts to different kinds of stresses in 3 species: Gracilaria tenuistipitata (Rhodophyta), Ostreococcus tauri (Chlorophyta) and Saccharum sp (Embryophyta). Automated measurement techniques for growth rate and photosynthesis were stablished for the red alga. This alga also showed, after establishment of reference genes for RT-qPCRs normalization, an overexpression of TRX during the first hour under water deficit. In O. tauri, where the central clock genes are known, changes in LOV-HK and TOC1 gene expression are related to a higher growth rate under low and high temperatures, respectively. Besides, a specific combination of light, temperature and salinity can be an important trigger of seasonal blooms that causes important transcriptional changes at the central oscillator, what is similar to land plants. In Saccharum sp tolerant to drought, photosynthesis rhythms and CCA1 expression change their phase under simulated water deficit and drought responsive transcripts like HVA-22 and DRP are significantly up-regulated. In short, stress resets the clock in Saccharum sp, increasing the period of photosynthesis oscillation. In O.tauri, it induces a higher growth, keeping clock features. It was not possible to verify clock responses to stress in G.tenuistipitata, but methods to do so were stablished. The biological clock responses to stress can provide invaluable information for the better understanding about the growth and reproduction of organisms with a high biotechnological potential
Asunto(s)
Relojes Circadianos , Eucariontes/clasificación , Estrés Psicológico/patología , Deshidratación/clasificación , Diagnóstico por Imagen/métodos , Gracilaria , Fotosíntesis , SaccharumRESUMEN
Imbalance of protein homeostasis (proteostasis) is known to cause cellular malfunction, cell death, and diseases. Elaborate regulation of protein synthesis and degradation is one of the important processes in maintaining normal cellular functions. Protein degradation pathways in eukaryotes are largely divided into proteasome-mediated degradation and lysosome-mediated degradation. Proteasome is a multisubunit complex that selectively degrades 80% to 90% of cellular proteins. Proteasome-mediated degradation can be divided into 26S proteasome (20S proteasome + 19S regulatory particle) and free 20S proteasome degradation. In 1980, it was discovered that during ubiquitination process, wherein ubiquitin binds to a substrate protein in an ATP-dependent manner, ubiquitin acts as a degrading signal to degrade the substrate protein via proteasome. Conversely, 20S proteasome degrades the substrate protein without using ATP or ubiquitin because it recognizes the oxidized and structurally modified hydrophobic patch of the substrate protein. To date, most studies have focused on protein degradation via 26S proteasome. This review describes the 26S/20S proteasomal pathway of protein degradation and discusses the potential of proteasome as therapeutic targets for cancer treatment as well as against diseases caused by abnormalities in the proteolytic system.
Asunto(s)
Adenosina Trifosfato , Muerte Celular , Eucariontes , Homeostasis , Estrés Oxidativo , Complejo de la Endopetidasa Proteasomal , Proteolisis , Ubiquitina , UbiquitinaciónRESUMEN
Abstract Quantification of bacteria being grazed by microzooplankton is gaining importance since they serve as energy subsidies for higher trophic levels which consequently influence fish production. Hence, grazing pressure on viable and non-viable fraction of free and particle-associated bacteria in a tropical estuary controlled mainly by protist grazers was estimated using the seawater dilution technique. In vitro incubations over a period of 42 h showed that at the end of 24 h, growth coefficient (k) of particle-associated bacteria was 9 times higher at 0.546 than that of free forms. Further, ‘k’ value of viable cells on particles was double that of free forms at 0.016 and 0.007, respectively. While bacteria associated with particles were grazed (coefficient of removal (g) = 0.564), the free forms were relatively less grazed indicating that particle-associated bacteria were exposed to grazers in these waters. Among the viable and non-viable forms, ‘g’ of non-viable fraction (particle-associated bacteria = 0.615, Free = 0.0086) was much greater than the viable fraction (particle-associated bacteria = 0.056, Free = 0.068). Thus, grazing on viable cells was relatively low in both the free and attached states. These observations suggest that non-viable forms of particle-associated bacteria were more prone to grazing and were weeded out leaving the viable cells to replenish the bacterial standing stock. Particle colonization could thus be a temporary refuge for the “persistent variants” where the viable fraction multiply and release their progeny.
Asunto(s)
Bacterias , Ecosistema , Microbiología Ambiental , Eucariontes , Agua de Mar/microbiología , Microbiología del Agua , BiodiversidadRESUMEN
When a ribosome complex is stalled during the translation elongation process in eukaryotes, the mono-ubiquitination of Rps3 has recently been shown to be critical to ribosome quality control. We have discovered that the regulatory role of Rps3 mono-ubiquitination is controlled by a deubiquitinase. We also showed that an autophagic signal appears to be coupled to the mono-ubiquitination of Rps3p through the entrance of Ubp3p into the autophagosome in yeasts. The mono-ubiquitination of the Rps3 protein is tightly modulated by reciprocal action between the Hel2p E3 ligase and the Ubp3p deubiquitinase in yeasts and the reciprocal action between the RNF123 E3 ligase and the USP10 deubiquitinase in mammalian cells. We also found that the Ubp3p/USP10 deubiquitinases critically modulate Hel2p/RNF123-mediated Rps3p mono-ubiquitination. In addition, we found that Hel2p/RNF123 and Ubp3p/USP10 appeared to be differently localized in the ribosome complex after ultraviolet irradiation. Together, our results support a model in which coordinated ubiquitination and deubiquitination activities can finely balance the level of regulatory Rps3p mono-ubiquitination in ribosome-associated quality control and autophagy processes.
Asunto(s)
Autofagia , Eucariontes , Control de Calidad , Ribosomas , Ubiquitina , Ubiquitina-Proteína Ligasas , Proteasas Ubiquitina-Específicas , Ubiquitinación , LevadurasRESUMEN
Varying length of messenger RNA (mRNA) 3′-untranslated region is generated by alternating the usage of polyadenylation sites during pre-mRNA processing. It is prevalent through all eukaryotes and has emerged as a key mechanism for controlling gene expression. Alternative polyadenylation (APA) plays an important role for cell growth, proliferation, and differentiation. In this review, we discuss the functions of APA related with various physiological conditions including cellular metabolism, mRNA processing, and protein diversity in a variety of disease models. We also discuss the molecular mechanisms underlying APA regulation, such as variations in the concentration of mRNA processing factors and RNA-binding proteins, as well as global transcriptome changes under cellular signaling pathway.
Asunto(s)
Humanos , Eucariontes , Expresión Génica , Metabolismo , Poliadenilación , Precursores del ARN , ARN Mensajero , Proteínas de Unión al ARN , Serina-Treonina Quinasas TOR , TranscriptomaRESUMEN
La leishmaniasis es una enfermedad producida por protozoarios parásitos del género Leishmania. Estos parásitos infectan a hospedadores mamíferos, entre los cuales los perros han sido implicados como reservorios del parásito. Este trabajo planteó estandarizar la técnica de la PCR-RFLP luego de la amplificación de la región ITS1 de Leishmania spp, como herramienta útil para la detección y caracterización molecular. Se utilizaron promastigotes de cultivo y muestras de biopsias procedentes de perros con leishmaniasis visceral previamente diagnosticados en el Centro Antirrábico Nacional. La región ITS1 del ADN genómico nuclear de Leishmania spp. fue amplificada utilizando los cebadores LITSR y L5,8S. La técnica ITS1 PCR-RFLP aplicada, permitió la detección de Leishmania (L) infantum en 10/10 aislados de parásitos mantenidos en medio NNN, en 10/18 muestras de bazo y 10/18 muestras de ganglio linfático poplíteo. Las condiciones óptimas de reacción fueron 0,2 mM de dNTPs, 0,1 pmol de cada cebador y 1U de Taq polimerasa. La sensibilidad de la PCR fue de 3 ng/µL de ADN en aislados de cultivo NNN y 60 ng/µL de ADN en muestras de biopsias, mientras que la especificidad fue de 100% para la detección de Leishmania sp. La enzima de restricción Hae III, determinó fragmentos de 184, 72 y 55 pb., que resultaron específicos para la especie Leishmania (L.) infantum. El marcador utilizado resultó confiable para la detección y caracterización de Leishmania sp. en perros procedentes de zonas endémicas, lo cual podría ser útil para verificar las especies de parásitos circulantes entre los perros.
Leishmaniasis is a disease caused by protozoan parasites of the genus Leishmania. The separasites infect to mammalian hosts, including canines that have been implicated as reservoirs of the parasite. The aim of this research was to standardize the technique of PCR RFLP after amplification of the ITS1 region of Leishmania (Leishmania) infantum, as a useful tool for detection and molecular characterization. Promastigotes from culture and biopsies from dogs with visceral Leishmaniasis previously diagnosed by the Centro Antirrábico Nacional. The ITS1 region of the genomic DNA of Leishmania sp. was amplified using LITSR and L5,8S primers. The technique ITS1 PCR-RFLP applied, allowed the detection of Leishmania (L.) infantum in 10/10 of the isolates from parasites maintained in NNN culture medium, in 10/18 samples from spleen and 10/18 samples from popliteal lymph node. Optimal reaction conditions were 0.2 mM dNTPs, 0.1 pmol of each primer and 1U of Taq polymerase. The sensitivity of PCR was 3 ng/µL DNA in isolates of parasites from NNNculture medium and 60 ng/µL DNA in biopsy samples while the specificity was 100% for the detection of DNA of Leishmania sp. The restriction enzyme Hae III determined fragments of184, 72 and 55 bp., which were specific to Leishmania (L.) infantum. The marker used isreliable for the detection and characterization of Leishmania sp. in dogs from endemic areas, which could be useful to verify the species of parasites circulating among animals.