A nivel mundial, 300 millones de personas están infectadas por el virus de la hepatitis B (VHB). A pesar de que existe una vacuna que previene la infección y se dispone de tratamiento antiviral que suprime la replicación del virus, no hay cura aún. El principal problema que evita la recuperación total del paciente, incluso para aquel que recibe tratamiento, es la persistencia de dos formas del genoma viral en los hepatocitos: el ADN circular covalentemente cerrado (ADNccc), el cual se encuentra en forma de episoma y tiene la capacidad de replicarse, y las secuencias lineales subge-nómicas que se integran en el genoma humano, con potencial oncogénico. Hasta el momento se dispone de unos pocos biomarcadores para monitorear o predecir la progresión de la enfermedad y la respuesta al tratamiento. Estos biomarcadores se detectan durante la infección, y son la base para la monitorización de la enfermedad y hacer un diagnóstico de la fase clínica de la infección. Recientemente han surgido nuevos biomarcadores como el antígeno relacionado con el core del virus de la hepatitis B (HBcrAg) y la detección del ARN del VHB, que parecen correlacionarse con los niveles transcripcionales del ADNccc, además, durante el tratamiento parecen ayudar a predecir la respuesta y podrían identificar aquellos a quienes se les puede suspender la terapia sin riesgo de recaída. En esta revisión, se describe la utilidad de los principales biomarcadores convencionales en hepatitis B, y se abordan los dos biomarcadores emergentes más estudiados que prometen evaluar el curso de la infección, al igual que determinar la progresión de la enfermedad y la respuesta al tratamiento.
Globally, 300 million people are infected with hepatitis B virus (HBV). Although there is a vaccine that prevents infection and antiviral treatment that suppresses the replication of the virus, there is still no cure. The main problem that prevents the total recovery of the patient, even for those who recei-ve treatment, is the persistence of two forms of the viral genome in hepatocytes: covalently close circular DNA (cccDNA), which is in the form of an episome that has the ability to replicate, and linear subgenomic sequences that are integrated into the human genome, with oncogenic potential. Few biomarkers are currently available to monitor or predict disease progression and response to treatment. These biomarkers are detected during infection and are the basis for monitoring the di-sease and making a diagnosis of the clinical phase of the infection. New biomarkers have recently emerged, such as hepatitis B core-related antigen (HBcrAg) and HBV RNA detection, which seem to correlate with cccDNA transcriptional levels while during treatment seem to help predict response, and could identify those for whom therapy can be discontinued without risk of relapse. In this review, the usefulness of the main conventional biomarkers in hepatitis B is described, and the two most studied emerging biomarkers are mentioned, which promise to evaluate the course of the infection, as well as to determine disease progression and treatment response.
Subject(s)Humans , Biomarkers , Hepatitis B virus , Hepatitis , Hepatitis B , DNA, Circular , RNA , Risk , Genome , Diagnosis , Antigens
We assessed the performance of MTBDRsl for detection of resistance to fluoroquinolones, aminoglycosides/cyclic peptides, and ethambutol compared to BACTEC MGIT 960 by subjecting simultaneously to both tests 385 phenotypically multidrug-resistant-Mycobacterium tuberculosis isolates from Sao Paulo, Brazil. Discordances were resolved by Sanger sequencing. MTBDRsl correctly detected 99.7% of the multidrug-resistant isolates, 87.8% of the pre-XDR, and 73.9% of the XDR. The assay showed sensitivity of 86.4%, 100%, 85.2% and 76.4% for fluoroquinolones, amikacin/kanamycin, capreomycin and ethambutol, respectively. Specificity was 100% for fluoroquinolones and aminoglycosides/cyclic peptides, and 93.6% for ethambutol. Most fluoroquinolone-discordances were due to mutations in genome regions not targeted by the MTBDRsl v. 1.0: gyrA_H70R and gyrB_R446C, D461N, D449V, and N488D. Capreomycin-resistant isolates with wild-type rrs results on MTBDRsl presented tlyA mutations. MTBDRsl presented good performance for detecting resistance to second-line drugs and ethambutol in clinical isolates. In our setting, multidrug-resistant. isolates presented mutations not targeted by the molecular assay.
Subject(s)Amikacin , Sensitivity and Specificity , Genome , Diagnosis , Mycobacterium tuberculosis
Despite several difficulties in chromosomal analyses of small-sized fishes, the cytogenetics of the Lebiasinidae was largely improved in the last years, showing differential patterns in the chromosomal evolution inside the family. In this context, it has been shown that genus Lebiasina preserves its karyotypic macrostructure, composed of 2n = 36 chromosomes, whereas the other genera generally present higher 2n. This study focused on the comparative cytogenetics of three Lebiasina species, one of them analyzed here for the first time, using conventional and molecular procedures. The results reinforced the differentiated evolutionary path of the genus Lebiasina while, at the same time, highlighted the genomic particularities that have accompanied the evolution of each species. In this sense, the repetitive components of the genome played a significant role in the differentiation of each species. It is also notable that L. minuta and L. melanoguttata, the two species that occur exclusively in the Brazilian territory, show greater chromosomal similarities to each other than to the trans-Andean sister species, L. bimaculata.(AU)
Apesar das dificuldades encontradas em se realizar análises cromossômicas em peixes de pequeno porte, os estudos citogenéticos em Lebiasinidae vêm crescendo nos últimos anos e demonstrando padrões diferenciados na evolução cromossômica entre os membros da família. Nesse contexto, o gênero Lebiasina tem mostrado preservar sua macroestrutura cariotípica, composta por 2n = 36 cromossomos, enquanto os demais gêneros geralmente apresentam 2n maiores. Este estudo tem como foco a citogenética comparativa de três espécies de Lebiasina, sendo uma delas analisada pela primeira vez aqui, através do emprego de técnicas convencionais e moleculares. Os resultados obtidos reforçam a trajetória evolutiva diferenciada do gênero Lebiasina, ao mesmo tempo em que evidenciam as particularidades genômicas que acompanham a evolução de cada uma das espécies. Neste contexto, os componentes repetitivos do genoma tiveram um papel importante na caracterização particular de cada uma das espécies. Também, é notável que L. minuta e L. melanoguttata, duas espécies que ocorrem exclusivamente no território brasileiro, apresentam maior proximidade citogenética entre elas do que com a espécie irmã transandina, L. bimaculata.(AU)
Subject(s)Animals , Chromosomes , Genome , Cytogenetics , Characiformes/genetics , Hybridization, Genetic
The eukaryotic genome is folded into higher-order conformation accompanied with constrained dynamics for coordinated genome functions. However, the molecular machinery underlying these hierarchically organized three-dimensional (3D) chromatin architecture and dynamics remains poorly understood. Here by combining imaging and sequencing, we studied the role of lamin B1 in chromatin architecture and dynamics. We found that lamin B1 depletion leads to detachment of lamina-associated domains (LADs) from the nuclear periphery accompanied with global chromatin redistribution and decompaction. Consequently, the inter-chromosomal as well as inter-compartment interactions are increased, but the structure of topologically associating domains (TADs) is not affected. Using live-cell genomic loci tracking, we further proved that depletion of lamin B1 leads to increased chromatin dynamics, owing to chromatin decompaction and redistribution toward nucleoplasm. Taken together, our data suggest that lamin B1 and chromatin interactions at the nuclear periphery promote LAD maintenance, chromatin compaction, genomic compartmentalization into chromosome territories and A/B compartments and confine chromatin dynamics, supporting their crucial roles in chromatin higher-order structure and chromatin dynamics.
Subject(s)Chromatin , Chromosomes , Genome , Humans , Lamin Type B/genetics
Graph-theory-based pathway analysis is a commonly used method for pathway searching in genome-scale metabolic networks. However, such searching often results in many pathways biologically infeasible due to the presence of currency metabolites (e.g. H+, H2O, CO2, ATP etc.). Several methods have been proposed to address the problem but up to now there is no well-recognized methods for processing the currency metabolites. In this study, we proposed a new method based on the function of currency metabolites for transferring of functional groups such as phosphate. We processed most currency metabolites as pairs rather than individual metabolites, and ranked the pairs based on their importance in transferring functional groups, in order to make sure at least one main metabolite link exists for any reaction. The whole process can be done automatically by programming. Comparison with existing approaches indicates that more biologically infeasible pathways were removed by our method and the calculated pathways were more reliable, which may facilitate the graph-theory-based pathway design and visualization.
Subject(s)Genome , Metabolic Networks and Pathways
The diverse thermophilic strains of Thermoanaerobacter, serving as unique platforms with a broad range of application in biofuels and chemicals, have received wide attention from scholars and practitioners. Although biochemical experiments and genome sequences have been reported for a variety of Thermoanaerobacter strains, an efficient genetic manipulation system remains to be established for revealing the biosynthetic pathways of Thermoanaerobacter. In line with this demand, the clustered regularly interspaced short palindromic repeat (CRISPR)/CRISPR-associated (Cas) systems for editing, regulating and targeting genomes have been well developed in thermophiles. Here, we reviewed and discussed the current status, associated challenges, and future perspectives of the construction of thermostable CRISPR/Cas9 genome editing systems for some representative Thermoanaerobacter species. The establishment, optimization, and application of thermostable CRISPR/Cas genome editing systems would potentially provide a foundation for further genetic modification of thermophilic bacteria.
Subject(s)Bacteria/genetics , CRISPR-Cas Systems/genetics , Gene Editing , Genome
Constraint-based genome-scale metabolic network models (genome-scale metabolic models, GEMs) have been widely used to predict metabolic phenotypes. In addition to stoichiometric constraints, other constraints such as enzyme availability and thermodynamic feasibility may also limit the cellular phenotype solution space. Recently, extended GEM models considering either enzymatic or thermodynamic constraints have been developed to improve model prediction accuracy. This review summarizes the recent progresses on metabolic models with multiple constraints (MCGEMs). We presented the construction methods and various applications of MCGEMs including the simulation of gene knockout, prediction of biologically feasible pathways and identification of bottleneck steps. By integrating multiple constraints in a consistent modeling framework, MCGEMs can predict the metabolic bottlenecks and key controlling and modification targets for pathway optimization more precisely, and thus may provide more reliable design results to guide metabolic engineering of industrially important microorganisms.
Subject(s)Genome , Metabolic Engineering , Metabolic Networks and Pathways/genetics , Models, Biological , Thermodynamics
Introducción. El carcinoma de endometrio es una patología heterogénea a nivel patogénico, histopatológico y molecular. En los últimos años se han sumado esfuerzos para esclarecer y aumentar el conocimiento de las bases moleculares, logrando así dividir las pacientes en cuatro subgrupos descritos por el Atlas del Genoma del Cáncer (TCGA, por sus siglas en inglés), obteniéndose valiosa información que afecta el diagnóstico, tratamiento y pronóstico de las pacientes con esta enfermedad. El objetivo de la siguiente revisión es exponer la nueva clasificación molecular del carcinoma de endometrio, así como discutir las ventajas que esta trae a la hora de estratificar a las pacientes y tomar decisiones terapéuticas. División de los temas tratados. Se realizó una búsqueda bibliográfica no sistemática en las bases de datos PubMed, Cochrane y Medline desde el año 2014 hasta el 2020 sobre el carcinoma de endometrio y su clasificación molecular. Se expone de manera concreta y actualizada el contexto histórico, los diferentes subgrupos moleculares y cómo estos impactan en el manejo de las pacientes. Conclusiones. El carcinoma de endometrio es una enfermedad heterogénea a nivel histopatológico, clínico y molecular. Con la nueva clasificación y los estudios prospectivos se podrán crear nuevas estrategias que permitan brindar mejores protocolos diagnósticos y terapéuticos.
Introduction. Endometrial carcinoma is a heterogeneous pathology in pathologenic, histopathological, and molecular terms. Over the last years, efforts have been made to clarify and increase knowledge of molecular bases, as such dividing patients into four subgroups described by the The Cancer Genome Atlas (TCGA), obtaining valuable information that affects the diagnosis, treatment, and prognosis of patients with this disease. The objective of this review is to exhibit the new molecular classification of endometrial carcinoma, and to discuss its advantages when stratifying patients and making therapeutic decisions. Division of Covered Topics. A non-systematic bibliographical search was carried out in the PubMed, Cochrane, and Medline databases from 2014 to 2020, on endometrial carcinoma and its molecular classification. The historical context, different molecular subgroups and how these impact patient handling are shown in a concrete and updated way. Conclusions. Endometrial carcinoma is a heterogeneous disease in histopathological, clinical, and molecular terms. With the new classification and the prospective studies, new strategies can be created to provide better diagnostic and therapeutic protocols.
Introdução. O carcinoma de endométrio é uma patologia heterogênea no nível patogênico, histopatológico e molecular. Nos últimos anos, foram feitos esforços para esclarecer e aumentar o conhecimento das bases moleculares, conseguindo dividir as pacientes em quatro subgrupos descritos pelo Atlas do Genoma do Câncer (TCGA, por suas siglas em inglês), obtendo informações valiosas que afetam o diagnóstico, o tratamento e o prognóstico das pacientes com esta doença. O objetivo da seguinte revisão é apresentar a nova classificação molecular do carcinoma de endométrio, bem como discutir as vantagens que ela traz no momento de estratificar as pacientes e tomar decisões terapêuticas. Divisão dos tópicos abordados. Uma pesquisa bibliográfica não sistemática foi realizada nas bases de dados PubMed, Cochrane e Medline de 2014 a 2020 sobre o carcinoma de endométrio e sua classificação molecular. São apresentados de forma concreta e atualizada o contexto histórico, os diferentes subgrupos moleculares e como esses têm impacto no tratamento das pacientes. Conclusões. O carcinoma de endométrio é uma doença heterogênea no nível histopatológico, clínico e molecular. Com a nova classificação e estudos prospectivos, novas estratégias podem ser desenvolvidas para fornecer melhores protocolos diagnósticos e terapêuticos.
Subject(s)Endometrial Neoplasms , Prognosis , Immunohistochemistry , Carcinoma , Genome , Endometrium
BACKGROUND: Brucella canis is the etiological agent of canine brucellosis, a worldwide neglected zoonosis that constitutes one of the major infectious causes of infertility and reproductive failure in dogs. Although genomic information available for this pathogen has increased in recent years, here we report the first genome sequencing of a B. canis strain in Chile, and the differences in virulence genes with other B. canis strains. RESULTS: Genome assembly produced a total length of 3,289,216 bp, N50 of 95,163 and GC% of 57.27, organized in 54 contigs in chromosome I, and 21 contigs in chromosome II. The genome annotation identified a total of 1981 CDS, 3 rRNA and 36 tRNA in chromosome I, and 1113 CDS and 10 tRNA in chromosome II. There is little variation between the different strains and the SCL isolate. Phylogenetic analysis showed that the Chilean SCL strain is closely related to B. canis and B. suis strains. Small differences were found when compared to the Serbian isolate, but all strains shared the same recent common ancestor. Finally, changes in the sequence of some virulence factors showed that the SCL strain is similar to other South American B. canis strains. CONCLUSIONS: This work sequenced and characterized the complete genome of B. canis strain SCL, evidencing the complete presence of all the genes of the virB operon, and minor changes in outer membrane proteins and in the urease operon. Our data suggest that B. canis was introduced from North America and then spread throughout the South American continent.
Subject(s)Animals , Dogs , Brucellosis/epidemiology , Brucella canis/genetics , Brucella canis/pathogenicity , Urease/genetics , Brucellosis/transmission , Zoonoses , Chile , Genome
O melanoma é um tipo de câncer de pele geneticamente diverso, que surge diante das transformações em melanócitos. A mutação BRAFV600E está presente em mais de 90% de todas as mutações em BRAF, sendo assim ocorre em cerca de 50% dos casos registrados. As mutações em NRAS, ocupam o segundo lugar entre as mutações mais prevalentes, cerca de 20% dos casos. Informações sobre as assinaturas genéticas, permitiram o desenvolvimento de terapia alvo dirigida. O Vemurafenib, inibidor da quinase BRAFV600E, apresentou inicialmente resultados bastante satisfatórios, contudo existe registro de casos de recidiva e resistência. O receptor aril de hidrocarbonetos é expresso em vários componentes da pele, e assim está relacionado a homeostase e fisiopatologia da pele. Diante disso, a avaliação da expressão do receptor em um painel de linhagens mutadas para NRAS e BRAF, e BRAF resistentes, mostrou-se maior do que a encontrada em melanócitos. Também encontramos maior expressão de mRNA de AhR em linhagens de melanoma derivadas de sítio primário e metastático, mutadas para BRAFV600E, quando comparadas ao melanócito. Agregado a isto, a análise in silico no TCGA (The Cancer Genome Atlas) mostrou que há 18% de alteração genética em AhR, sendo em maior parte a alta regulação de mRNA. Também, a análise do banco público GSE12391, mostrou aumento de mRNA de AhR na fase de crescimento vertical do melanoma. Assim, concluímos que há maior expressão de mRNA e sua importância nas fases de desenvolvimento do melanoma, tanto nos processos iniciais quanto em processos de migração, invasão e metástase. Ainda, encontramos maior mRNA do receptor em linhagens resistentes ao Vemurafenib. Este resultado sustenta a hipótese de que AhR pode ser considerado um marcador de resistência em melanomas. O AhR, inicialmente no citoplasma, quando ativado pode atuar como fator de transcrição regulando vários genes que apresentam sequências definidas, participando de respostas carcinogênicas. Compostos halogenados e moléculas endógenas derivadas das vias de metabolização do triptofano são agonistas do receptor. Anteriormente, nosso grupo mostrou que linhagens de melanoma incubadas com triptamina e DMT exibiram menor clonogenicidade. Diante de uma literatura escassa sobre o papel do DMT no melanoma e com base nestes resultados, nosso objetivo foi avaliar o papel de AhR nesta interface DMT-melanoma. Para isto, nosso objetivo foi construir linhagem editada geneticamente para AhR através da ferramenta CRISPR-Cas9. Vários foram os esforços, sem sucesso, utilizados nas tentativas de comprovar a manutenção de células editadas na cultura. Atrelamos a este resultado a possibilidade de haver duas subpopulações editadas geneticamente pós CRISPR-Cas9, onde uma destas manteve o padrão de crescimento semelhante às células wild type. Devido a este crescimento diferencial, não obtivemos congruências nos ensaios e postulamos a perda do possível nocaute. A partir disso, realizamos ensaios de interactoma para avaliar a interação de DMT-AhR. Nosso resultado sugere a interação de DMT ao receptor sigma 1, e não ao receptor aril de hidrocarbonetos. Desta forma, o interactoma sustenta a hipótese de que DMT não é um ligante de AhR. Para certificar este resultado análises de docking associados a ensaios biológicos, avaliando o papel do receptor, devem ser realizados para averiguar a afinidade e seletividade de DMT como ligante do receptor na linhagem de melanoma
Melanoma is a genetically diverse type of skin cancer, which arises from changes in melanocytes. The BRAFV600E mutation is present in more than 90% of all BRAF mutations, so it occurs in about 50% of registered cases. Mutations in NRAS occupy the second place among the most prevalent mutations, about 20% of cases. Information on genetic signatures allowed the development of targeted therapy. vemurafenib, kinase inhibitor BRAFV600E, initially presented very satisfactory results, however there is a record of cases of relapse and resistance. The aryl hydrocarbon receptor is expressed in several components of the skin and is thus related to homeostasis and skin pathophysiology. Therefore, the evaluation of receptor expression in a panel of strains mutated to NRAS and BRAF, and resistant BRAF, proved to be greater than that found in melanocytes. We also found main expression of AhR mRNA in melanoma strains derived from primary and metastatic site, mutated to BRAFV600E, when compared to melanocyte. Added to this, the in silico analysis in TCGA (The Cancer Genome Atlas) showed that there is 18% of genetic alteration in AhR, being mostly the high regulation of mRNA. Also, an analysis by the public bank GSE12391, showed an increase in AhR mRNA in the vertical growth phase of melanoma. Thus, it is concluded that there is greater expression of mRNA and its importance in the stages of development of melanoma, both in recent processes and in the processes of migration, invasion and metastasis. In addition, we found higher receptor mRNA in strains resistant to vemurafenib. This result supports the hypothesis that AhR can be considered a marker of resistance in melanomas. AhR, initially in the cytoplasm, when activated can act as a transcription factor regulating several genes that have defined sequences, participating in carcinogenic responses. Along with this, we show that along the tumor progression, there is an increase in AhR in the radial growth phase of melanoma. Halogenated compounds and endogenous molecules derived from the tryptophan metabolism pathways are receptor agonists. Previously, our group showed that melanoma strains incubated with tryptamine and DMT exhibited less clonogenicity. In view of a scarce literature on the role of DMT in melanoma and based on these results, our objective was to evaluate the role of AhR in this DMT-melanoma interface. For this, our goal was to build genetically edited strain for AhR using the CRISPR-Cas9 tool. Several efforts were unsuccessful in attempts to prove the maintenance of cells edited in the culture. We linked to this result the possibility of having two subpopulations genetically edited after CRISPR-Cas9, where one of them maintained the growth pattern like wild type cells. Due to this differential growth, we did not obtain congruence in the tests and postulated the loss of the possible knockout. From that, we performed interactome assays to evaluate the DMT-AhR interaction. Our result suggests the interaction of DMT with the sigma 1 receptor, and not the aryl hydrocarbon receptor. Thus, the interactome supports the hypothesis that DMT is not an AhR ligand. To certify this result, docking analyses associated with biological assays, evaluating the role of the receptor, should be performed to ascertain the affinity and selectivity of DMT as a ligand of the receptor in the melanoma lineage
Subject(s)Skin/injuries , Genome , Receptors, Aryl Hydrocarbon , Melanocytes/classification , Melanoma , Neoplasms/pathology , Phosphotransferases/antagonists & inhibitors , Association , Transcription Factors/agonists , Cytoplasm/classification , Human Migration
Cancer cell lines are widely used as in vitro models of tumorigenesis, facilitating fundamental discoveries in cancer biology and translational medicine. Currently, there are few options for glioblastoma (GBM) treatment and limited in vitro models with accurate genomic and transcriptomic characterization. Here, a detailed characterization of a new GBM cell line, namely AHOL1, was conducted in order to fully characterize its molecular composition based on its karyotype, copy number alteration (CNA), and transcriptome profiling, followed by the validation of key elements associated with GBM tumorigenesis. Large numbers of CNAs and differentially expressed genes (DEGs) were identified. CNAs were distributed throughout the genome, including gains at Xq11.1-q28, Xp22.33-p11.1, Xq21.1-q21.33, 4p15.1-p14, 8q23.2-q23.3 and losses at Yq11.21-q12, Yp11.31-p11.2, and 15q11.1-q11.2 positions. Nine druggable genes were identified, including HCRTR2, ETV1, PTPRD, PRKX, STS, RPS6KA6, ZFY, USP9Y, and KDM5D. By integrating DEGs and CNAs, we identified 57 overlapping genes enriched in fourteen pathways. Altered expression of several cancer-related candidates found in the DEGs-CNA dataset was confirmed by RT-qPCR. Taken together, this first comprehensive genomic and transcriptomic landscape of AHOL1 provides unique resources for further studies and identifies several druggable targets that may be useful for therapeutics and biologic and molecular investigation of GBM.
Subject(s)Humans , Glioblastoma/genetics , Gene Expression Regulation, Neoplastic , Minor Histocompatibility Antigens , Genome , Genomics , Cell Line, Tumor , Histone Demethylases , Transcriptome
Uno de los rasgos de la sociedad del siglo XXI es la incorporación de las TIC en la educación, las cuales pueden contribuir en los procesos de enseñanza-aprendizaje. Sin embargo, el maestro es quien le dá el sentido pedagógico a estos recursos educativos. En ese sentido, las herramientas de la bioinformática pueden contribuir en la enseñan-za de temas complejos y abstractos con ejemplos concretos y sin necesidad de realizar prácticas de laboratorio que representen elevados costos económicos. Considerando lo anterior, en esta investigación se presenta el diseño de la guía "Análisis de la variabilidad genética en especies de Pseudomonas mediante comparación de los mapas de restricción del gen ptsN", que utilizó dos sitios web gratuitos y que muestra paso a paso la manera de realizarla. La guía se aplicó a 30 estudiantes de la asignatura "biología molecular" del período 2018-1 de la licenciatura en biología de la UPN. Para la recolección de la información que permitió evaluar el aprendizaje y conocer la percepción de los estudiantes respecto de la pertinencia y viabilidad del recurso educativo se emplearon un cuestionario y una encuesta estructurada. Después de trabajar con la guía, los estudiantes mostraron un progreso signifi cativo en sus bagajes cognitivo, conceptual y procedimental, hecho que se evidencia en las respuestas obtenidas mediante los instrumentos diseña-dos. Tras la experiencia, los estudiantes consideraron que la guía era apropiada y viable para enseñar variabilidad genética. Adicionalmente, se hizo evidente que sí es posible diseñar actividades contextualizadas a bajo costo.
One of the features of the 21st century society is the incorporation of ICT in education, which can contribute to the teaching-learning processes. However, it is the teacher who gives the pedagogical meaning to these educational resources. In this sense, bioinformatics tools can contribute to the teaching of complex and abstract topics with concrete examples and without the need for laboratory practices that represent high economic costs. Considering the above, this research presents the design of the guide "Analysis of genetic variability in Pseudomonas species by comparison of restriction maps of the ptsN gene", which used two free websites and shows step by step how to perform it. The guide was applied to 30 students of the subject "molecular biology" of the period 2018-1 of the bachelor's degree in biology at UPN. A questionnaire and a structured survey were used to collect information to evaluate learning and to know the students' perception of the relevance and feasibility of the educational resource. After working with the guide, students showed signifi cant progress in their cognitive, conceptual and procedural baggage, as evidenced by the answers obtained through the designed instruments. After the experience, the students considered that the guide was appropriate and viable for teaching genetic variability. Additionally, it became evident that it is possible to design contextualized activities at low cost.
Subject(s)Adult , Computational Biology , Genetic Variation , Genome
Cases of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in Manaus, Brazil, resurged in late 2020 despite previously high levels of infection. Genome sequencing of viruses sampled in Manaus between November 2020 and January 2021 revealed the emergence and circulation of a novel SARS-CoV-2 variant of concern. Lineage P.1 acquired 17 mutations, including a trio in the spike protein (K417T, E484K, and N501Y) associated with increased binding to the human ACE2 (angiotensin-converting enzyme 2) receptor. Molecular clock analysis shows that P.1 emergence occurred around mid-November 2020 and was preceded by a period of faster molecular evolution. Using a two-category dynamical model that integrates genomic and mortality data, we estimate that P.1 may be 1.7- to 2.4-fold more transmissible and that previous (non-P.1) infection provides 54 to 79% of the protection against infection with P.1 that it provides against non-P.1 lineages. Enhanced global genomic surveillance of variants of concern, which may exhibit increased transmissibility and/or immune evasion, is critical to accelerate pandemic responsiveness.
Subject(s)Angiotensins , Genome , Betacoronavirus
Natural products, important sources of innovative drugs, food, spices and daily chemicals, are closely related to people's healthy life. With the development and integration of modern biological and chemical technologies of natural products, the researches on biosynthesis of natural products have made great progresses in recent years. The biosynthetic pathways of a number of natural products have been analyzed. Many pathway enzymes and modifying enzymes involved in the biosynthesis of natural products have been mined and functionally characterized. Furthermore, genes encoding pathway enzymes have been introduced into chassis to construct cell factories producing natural products through synthetic biology technologies. Also, other biotechnologies including genome editing and genome mining, have been used in the biosynthesis of natural products. In order to further promote the development of researches on biosynthesis of natural products, we edited a Special Issue on the topic of "biosynthesis of natural products", focusing on the researches progress in three aspects: the analysis of biosynthetic pathways of natural products, genome-wide mining and functional characterization of genes encoding tool enzymes, and the scale preparation of natural products by biosynthetic technology. Also included in this Special Issue was the prospect of the biosynthesis of natural products. This Special Issue can provide reference and guidance for the further development of natural product biosynthesis.
Subject(s)Biological Products , Biosynthetic Pathways/genetics , Biotechnology , Genome , Synthetic Biology
Genome-scale metabolic network model (GSMM) is becoming an important tool for studying cellular metabolic characteristics, and remarkable advances in relevant theories and methods have been made. Recently, various constraint-based GSMMs that integrated genomic, transcriptomic, proteomic, and thermodynamic data have been developed. These developments, together with the theoretical breakthroughs, have greatly contributed to identification of target genes, systems metabolic engineering, drug discovery, understanding disease mechanism, and many others. This review summarizes how to incorporate transcriptomic, proteomic, and thermodynamic-constraints into GSMM, and illustrates the shortcomings and challenges of applying each of these methods. Finally, we illustrate how to develop and refine a fully integrated GSMM by incorporating transcriptomic, proteomic, and thermodynamic constraints, and discuss future perspectives of constraint-based GSMM.
Subject(s)Genome/genetics , Metabolic Engineering , Metabolic Networks and Pathways/genetics , Models, Biological , Proteomics
Aspergillus niger is a vital industrial workhouse widely used for the production of organic acids and industrial enzymes. This fungus is a crucial cell factory due to its innate tolerance to a diverse range of abiotic conditions, high production titres, robust growth during industrial scale fermentation, and status as a generally recognized as safe (GRAS) organism. Rapid development of synthetic biology and systems biology not only offer powerful approaches to unveil the molecular mechanisms of A. niger productivity, but also provide more new strategies to construct and optimize the A. niger cell factory. As a new generation of genome editing technology, the Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)/CRISPR associated (Cas) system brings a revolutionary breakthrough in targeted genome modification for A. niger. In this review, we focus on current advances to the CRISPR/Cas genome editing toolbox, its application on gene modification and gene expression regulation in this fungal. Moreover, the future directions of CRISPR/Cas genome editing in A. niger are highlighted.
Subject(s)Aspergillus niger/genetics , CRISPR-Cas Systems/genetics , Clustered Regularly Interspaced Short Palindromic Repeats/genetics , Gene Editing , Genome
El artículo se centra en la utilización de la nueva herramienta, CRISPR (repeticiones palindrómicas cortas agrupadas a intervalos regulares), la cual permite editar los genomas de los seres vivos de manera más precisa que otras técnicas; a lo largo del artículo se mencionan trabajos relacionados con la detención de la angiogénesis, cáncer, Sarcoma de Kaposi en inmunodeficiencias, Parkinson, regeneración y modificación genética en humanos, todas estas investigaciones tiene en común la utilización de la herramienta CRISPR. También se comenta las complicaciones éticas que conlleva utilizar esta tecnología en el ADN de células embrionarias humanas, que según diferentes criterios, podrían llevar a generar seres humanos mejorados, es decir no solo sin susceptibilidad a enfermedades degenerativas o incurables, sino también modificados en aspectos físicos que no necesariamente estarían ligados a alguna patología.
The article focuses on the use of the new tool, CRISPR (short palindromic repetitions grouped at regular intervals), which allows editing the genomes of living beings more accurately than other techniques; Throughout the article, works related to the arrest of angiogenesis, cancer, Kaposis sarcoma in immunodeficiencies, Parkinsons, regeneration and genetic modification in humans are mentioned, all these investigations have in common the use of the CRISPR tool. You can also comment on the ethical complications that involve using this technology in the DNA of human embryonic cells, which according to different criteria, carry out improved human beings, that is not only without susceptibility to degenerative or incurable diseases, but also modified in physical aspects that are not linked to any pathology.
Subject(s)DNA , Clustered Regularly Interspaced Short Palindromic Repeats , Sarcoma, Kaposi , Cells , Genome , Genetics , Neoplasms
BACKGROUND: Cultivated peanut (Arachis hypogaea. L) represents one of the most important oil crops in the world. Although much effort has been expended to characterize microsatellites or Simple Sequence Repeats (SSRs) in peanut, the quantity and quality of the markers in breeding applications remain limited. Here, genome-wide SSR characterization and marker development were performed using the recently assembled genome of the cultivar Tifrunner. RESULTS: In total, 512,900 microsatellites were identified from 2556.9-Mb genomic sequences. Based on the flanking sequences of the identified microsatellites, 7757 primer pairs (markers) were designed, and further evaluated in the assembled genomic sequences of the tetraploid Arachis cultivars, Tifrunner and Shitouqi, and the diploid ancestral species, A. duranensis and A. ipaensis. In silico PCR analysis showed that the SSR markers had high amplification efficiency and polymorphism in four Arachis genotypes. Notably, nearly 60% of these markers were single-locus SSRs in tetraploid Arachis species, indicating they are more specific in distinguishing the alleles of the A and B sub-genomes of peanut. In addition, two markers closely related with purple testa color and 27 markers near to FAD2 genes were identified, which could be used for breeding varieties with purple testa and high-oleic acid content, respectively. Moreover, the potential application of these SSR markers in tracking introgressions from Arachis wild relatives was discussed. CONCLUSIONS: This study reported the development of genomic SSRs from assembled genomic sequences of the tetraploid Arachis Tifrunner, which will be useful for diversity analysis, genetic mapping and functional genomics studies in peanut
Subject(s)Arachis/genetics , Breeding/methods , Microsatellite Repeats , Polymorphism, Genetic , Genetic Markers , Polymerase Chain Reaction , Genome , Crops, Agricultural
Given their relationship with metabolic syndrome and systematic inflammatory diseases, the pathogenesis of hypertension, hyperglycemia, and hyperlipidemia is closely related. To explore the common genes among these three conditions, spontaneous hypertensive rats (SHR), spontaneous diabetic Goto-Kakizaki rats (GK) and hyperlipidemia rats (HMR) were reared for experiments. Gene array was used to identify the genes of SHR, GK and HMR compared with normal Wistar rats using TBtools software. First, real-time PCR was applied to verify these genes, and Cytoscape software was used to construct networks based on the National Center for Biotechnology Information (NCBI) database. Second, Kyoto Encyclopedia of Genes and Genomes (KEGG) database analysis was performed to classify the genes. Visualization and Integrated Discovery (DAVID) database and Gene Ontology database were used to explore the biological function. Finally, Onto-tools Pathway Express was used to analyze the pathways of shared genes. Importantly, upregulated common genes, such as Bad, Orm1, Arntl and Zbtb7a, were used to construct a network of 150 genes, while downregulated genes, such as Mif and Gpx1, formed a network of 29 genes. Interestingly, the networks were involved in various pathways, such as insulin signal pathway, endometrial cancer pathway, circadian rhythm pathway, and pancreatic cancer pathway. We discovered common genes of SHR, GK and HMR compared with normal Wistar rats, and the association of these genes together with biological function were preliminarily revealed.
Subject(s)Animals , Male , Female , Rats , Diabetes Mellitus/pathology , Genes/genetics , Hyperlipidemias/pathology , Hypertension/pathology , Biological Products/adverse effects , Software , Genome/physiology , Scientists for Health and Research for Development , Real-Time Polymerase Chain Reaction
PURPOSE: We investigated the expression of the N-myc and STAT interactor (NMI) protein in invasive ductal carcinoma tissue and estimated its clinicopathologic significance as a prognostic factor. The expression levels and prognostic significance of NMI were also analyzed according to the molecular subgroup of breast cancers.METHODS: Human NMI detection by immunohistochemistry was performed using tissue microarrays of 382 invasive ductal carcinomas. The correlation of NMI expression with patient clinicopathological parameters and prognostic significance was analyzed and further assessed according to the molecular subgroup of breast cancers. Moreover, in vitro experiments with 13 breast cancer cell lines were carried out. We also validated NMI expression significance in The Cancer Genome Atlas cohort using the Human Protein Atlas (HPA) database.RESULTS: Low NMI expression was observed in 190 cases (49.7%). Low NMI expression was significantly associated with the “triple-negative” molecular subtype (p < 0.001), high nuclear grade (p < 0.001), high histologic grade (p < 0.001), and advanced anatomic stage (p = 0.041). Patients with low NMI expression had poorer progression-free survival (p = 0.038) than patients with high NMI expression. Low NMI expression was not significantly associated with patient prognosis in the molecular subgroup analysis. In vitro, a reduction of NMI expression was observed in 8 breast cancer cell lines, especially in the estrogen receptor-positive and basal B type of triple-negative breast cancer molecular subgroups. The HPA database showed that low NMI expression levels were associated with a lower survival probability compared with that associated with high NMI expression (p = 0.053).CONCLUSION: NMI expression could be a useful prognostic biomarker and a potential novel therapeutic target in invasive ductal carcinoma.