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1.
Int Microbiol ; 25(1): 17-26, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34185162

RESUMO

The life cycle of Ustilago maydis involves alternation of a haploid saprophytic yeast-like stage and a dikaryotic hyphal virulent form. Under in vitro conditions, basidiocarps are formed. Analysis of the transcriptional network of basidiocarp formation revealed the possible involvement of a Tec transcription factor (Tec1, UMAG_02835) in the process. In some Ascomycota, Tec factors are involved in mycelial formation, pathogenesis, and interaction with other regulatory elements, but their role in Basidiomycota species is almost unknown. Accordingly, we proceeded to determine the role of this gene in U. maydis by its mutation. Tec1 was found to be a crucial factor for normal mating, basidiocarp development, and virulence, all of the functions related to the dikaryotic stage dependent of the b genes, whereas dimorphism and resistance to different stress conditions occurring in the haploid stage were not affected in tec1 mutants. The observation that mutants showed a low residual wild-type phenotype suggests the presence of a secondary mechanism that partially compensates the loss of Tec1.


Assuntos
Basidiomycota , Ustilago , Carpóforos , Proteínas Fúngicas/genética , Fatores de Transcrição/genética , Ustilago/genética , Virulência
2.
Int J Mol Sci ; 23(22)2022 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-36430314

RESUMO

Potato microtuber (MT) development through in vitro techniques are ideal propagules for producing high quality potato plants. MT formation is influenced by several factors, i.e., photoperiod, sucrose, hormones, and osmotic stress. We have previously developed a protocol of MT induction in medium with sucrose (8% w/v), gelrite (6g/L), and 2iP as cytokinin under darkness. To understand the molecular mechanisms involved, we performed a transcriptome-wide analysis. Here we show that 1715 up- and 1624 down-regulated genes were involved in this biological process. Through the protein-protein interaction (PPI) network analyses performed in the STRING database (v11.5), we found 299 genes tightly associated in 14 clusters. Two major clusters of up-regulated proteins fundamental for life growth and development were found: 29 ribosomal proteins (RPs) interacting with 6 PEBP family members and 117 cell cycle (CC) proteins. The PPI network of up-regulated transcription factors (TFs) revealed that at least six TFs-MYB43, TSF, bZIP27, bZIP43, HAT4 and WOX9-may be involved during MTs development. The PPI network of down-regulated genes revealed a cluster of 83 proteins involved in light and photosynthesis, 110 in response to hormone, 74 in hormone mediate signaling pathway and 22 related to aging.


Assuntos
Solanum tuberosum , Solanum tuberosum/metabolismo , Escuridão , Transcriptoma , Hormônios/metabolismo , Sacarose/metabolismo
3.
Arch Microbiol ; 202(1): 93-103, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31485712

RESUMO

We have described that formation of basidiocarps by Ustilago maydis requires illumination. In the current research, we have proceeded to analyze what kind of light receptors are involved in this phenomenon. Accordingly, we investigated whether the homologues of the White Collar (WC), and the phytochrome (PHY) genes played a role in this process. Mutants deficient in either one of the three U. maydis WC homologue genes (WCO1a, WCO1b, WCO2), or the phytochrome-encoding the PHY gene were obtained. Phenotypic analysis of the mutants showed that ∆wco1a mutants formed similar numbers of basidiocarps than wild-type strain, whereas ∆wco1b mutants were severely affected in basidiocarp formation when illuminated with white, blue or red light. ∆wco2 and ∆phy1 mutants did not form basidiocarps under any illumination condition. These data indicate that Wco1a is the main blue light receptor, and Wco1b may operate as a secondary blue light receptor; Phy1 is the red light receptor, and Wco2 the transcription factor that controls the photo stimulation of the genes involved in the formation of fruiting bodies. It is suggested that effectiveness of the light receptors depends on the whole structure of the complex, possibly, because their association is necessary to maintain their functional structure.


Assuntos
Carpóforos/fisiologia , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Fotorreceptores Microbianos/genética , Fotorreceptores Microbianos/metabolismo , Ustilago/fisiologia , Carpóforos/efeitos da radiação , Ustilago/genética , Ustilago/efeitos da radiação
4.
Palliat Support Care ; 18(5): 557-568, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32127071

RESUMO

OBJECTIVE: The functional assessment of cancer therapy-bone marrow transplant (FACT-BMT) is a widely used instrument to assess quality of life (QOL) in hematopoietic stem cell transplant (HSCT) patients, but there is little evidence of its validity in Latin American populations. This study evaluated the psychometric properties of the Spanish language version of the FACT-BMT in Mexican patients. METHOD: First, the original version was piloted with 15 HSCT patients to obtain an adequate cultural version, resulting in the adaptation of one item. After that, the new version was completed by 139 HSCT patients. RESULTS: The results showed a FACT factor structure that explains 70.84% of the total variance, a factor structure similar to the original FACT structure, and with a high internal consistency (Cronbach's alpha = 0.867). For the BMT subscale, the best factor structure included 17 items which explain 61.65% of the total variance with an adequate internal consistency (Cronbach's alpha = 0.696). SIGNIFICANCE OF THE RESULTS: The FACT-BMT was found to be a valid and reliable instrument to evaluate QOL in Mexican patients. Our results constitute new FACT-BMT empirical evidence that supports its clinical and research uses.


Assuntos
Transplante de Medula Óssea/normas , Neoplasias Ósseas/terapia , Pacientes/psicologia , Psicometria/normas , Qualidade de Vida/psicologia , Adulto , Transplante de Medula Óssea/métodos , Transplante de Medula Óssea/estatística & dados numéricos , Neoplasias Ósseas/psicologia , Feminino , Humanos , Masculino , México , Pessoa de Meia-Idade , Pacientes/estatística & dados numéricos , Psicometria/instrumentação , Psicometria/métodos , Reprodutibilidade dos Testes , Inquéritos e Questionários , Tradução
5.
Rev Invest Clin ; 70(3): 117-120, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29943775

RESUMO

Cancer patients are particularly susceptible to undernourishment so associated weight loss is frequent. Approximately 15% of patients lose >10% of their usual body weight, 40-80% become undernourished, and about 20% die as a result. Well-nourished patients have a higher survival rate when compared with patients at risk of undernourishment (19.9 vs. 3.7 months); hence, nutritional intervention is pivotal. Undernourishment negatively influences the patient's prognosis, and its prevalence depends on the tumor type and location, disease stage, treatment, and the applied nutritional evaluation tool. During abdominopelvic radiotherapy, up to 90% of patients experience symptoms of varying severity; weight loss during radiotherapy is an early indicator of nutritional deterioration, and he the use of radiation is associated with a higher likelihood of undernourishment. In patients with gynecological malignancies, 12.5-54% are malnourished before receiving oncological treatment, worsening after treatment in 35.8-82% of cases. There is also deterioration of the nutritional status in patients with colorectal cancer once pelvic radiotherapy is initiated, whereby 50% of cases are malnourished at the beginning of treatment, and 66.7% are so when it ends. Although there are notable differences in the impact of radiotherapy on weight according to the radiated region, 88% patients receiving abdominal radiotherapy were found to lose weight compared to 38% of patients whose treatment was limited to the pelvis.


Assuntos
Neoplasias Abdominais/complicações , Estado Nutricional , Neoplasias Pélvicas/complicações , Neoplasias Abdominais/terapia , Quimiorradioterapia/efeitos adversos , Quimiorradioterapia/métodos , Humanos , Desnutrição/epidemiologia , Desnutrição/etiologia , Apoio Nutricional/métodos , Neoplasias Pélvicas/terapia , Taxa de Sobrevida , Redução de Peso
6.
ORL J Otorhinolaryngol Relat Spec ; 78(6): 320-333, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28125819

RESUMO

We review clinical trials of squamous cell carcinoma of the head and neck (SCCHN) to address the current and potential uses of cetuximab (CTX). PubMed was reviewed to identify papers published between 2010 and 2016. The search terms used were "cetuximab" and "head and neck cancer." A total of 634 articles were identified. Phase II or III studies with CTX in patients with advanced SCCHN without treatment or with recurrent/metastatic tumors were selected. Forty-six registries were obtained. Information was critically reviewed and relevant information presented. As definitive treatment of advanced squamous cells carcinomas and as palliative treatment of recurrent/metastatic disease, CTX alone or associated with chemotherapy and/or radiotherapy is an alternative to chemoradiotherapy because of its distinct and favorable toxicity profile.


Assuntos
Antineoplásicos Imunológicos/uso terapêutico , Carcinoma de Células Escamosas/tratamento farmacológico , Cetuximab/uso terapêutico , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/radioterapia , Terapia Combinada , Neoplasias de Cabeça e Pescoço/patologia , Neoplasias de Cabeça e Pescoço/radioterapia , Humanos , Carcinoma de Células Escamosas de Cabeça e Pescoço
7.
PLoS One ; 19(4): e0301169, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38557903

RESUMO

At present, the development of plants with improved traits like superior quality, high yield, or stress resistance, are highly desirable in agriculture. Accelerated crop improvement, however, must capitalize on revolutionary new plant breeding technologies, like genetically modified and gene-edited crops, to heighten food crop traits. Genome editing still faces ineffective methods for the transformation and regeneration of different plant species and must surpass the genotype dependency of the transformation process. Tomato is considered an alternative plant model system to rice and Arabidopsis, and a model organism for fleshy-fruited plants. Furthermore, tomato cultivars like Micro-Tom are excellent models for tomato research due to its short life cycle, small size, and capacity to grow at high density. Therefore, we developed an indirect somatic embryo protocol from cotyledonary tomato explants and used this to generate epigenetically edited tomato plants for the SlWRKY29 gene via CRISPR-activation (CRISPRa). We found that epigenetic reprogramming for SlWRKY29 establishes a transcriptionally permissive chromatin state, as determined by an enrichment of the H3K4me3 mark. A whole transcriptome analysis of CRISPRa-edited pro-embryogenic masses and mature somatic embryos allowed us to characterize the mechanism driving somatic embryo induction in the edited tomato cv. Micro-Tom. Furthermore, we show that enhanced embryo induction and maturation are influenced by the transcriptional effector employed during CRISPRa, as well as by the medium composition and in vitro environmental conditions such as osmotic components, plant growth regulators, and light intensity.


Assuntos
Solanum lycopersicum , Solanum lycopersicum/genética , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Melhoramento Vegetal , Desenvolvimento Embrionário , Regeneração , Edição de Genes , Plantas Geneticamente Modificadas/genética , Sistemas CRISPR-Cas/genética , Genoma de Planta
8.
Genes (Basel) ; 14(7)2023 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-37510367

RESUMO

Potatoes have emerged as a key non-grain crop for food security worldwide. However, the looming threat of climate change poses significant risks to this vital food source, particularly through the projected reduction in crop yields under warmer temperatures. To mitigate potential crises, the development of potato varieties through genome editing holds great promise. In this study, we performed a comprehensive transcriptomic analysis to investigate microtuber development and identified several differentially expressed genes, with a particular focus on ribosomal proteins-RPL11, RPL29, RPL40 and RPL17. Our results reveal, by protein-protein interaction (PPI) network analyses, performed with the highest confidence in the STRING database platform (v11.5), the critical involvement of these ribosomal proteins in microtuber development, and highlighted their interaction with PEBP family members as potential microtuber activators. The elucidation of the molecular biological mechanisms governing ribosomal proteins will help improve the resilience of potato crops in the face of today's changing climatic conditions.


Assuntos
Solanum tuberosum , Solanum tuberosum/genética , Produtos Agrícolas , Perfilação da Expressão Gênica , Temperatura , Proteínas Ribossômicas/genética
9.
Plants (Basel) ; 12(20)2023 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-37896100

RESUMO

The known activities of cytokinins (CKs) are promoting shoot multiplication, root growth inhibition, and delaying senescence. 6-Benzylaminopurine (BAP) has been the most effective CK to induce shoot proliferation in cereal and grasses. Previously, we reported that in lemongrass (Cymbopogon citratus) micropropagation, BAP 10 µM induces high shoot proliferation, while the natural CK 6-(γ,γ-Dimethylallylamino)purine (2-iP) 10 µM shows less pronounced effects and developed rooting. To understand the molecular mechanisms involved, we perform a protein-protein interaction (PPI) network based on the genes of Brachypodium distachyon involved in shoot proliferation/repression, cell cycle, stem cell maintenance, auxin response factors, and CK signaling to analyze the molecular mechanisms in BAP versus 2-iP plants. A different pattern of gene expression was observed between BAP- versus 2-iP-treated plants. In shoots derived from BAP, we found upregulated genes that have already been demonstrated to be involved in de novo shoot proliferation development in several plant species; CK receptors (AHK3, ARR1), stem cell maintenance (STM, REV and CLV3), cell cycle regulation (CDKA-CYCD3 complex), as well as the auxin response factor (ARF5) and CK metabolism (CKX1). In contrast, in the 2-iP culture medium, there was an upregulation of genes involved in shoot repression (BRC1, MAX3), ARR4, a type A-response regulator (RR), and auxin metabolism (SHY2).

10.
Plant Sci ; 329: 111617, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36731748

RESUMO

With the continuous deterioration of arable land due to an ever-growing population, improvement of crops and crop protection have a fundamental role in maintaining and increasing crop productivity. Alternatives to the use of pesticides encompass the use of biological control agents, generation of new resistant crop cultivars, the application of plant activator agrochemicals to enhance plant defenses, and the use of gene editing techniques, like the CRISPR-Cas system. Here, we test the hypothesis that epigenome editing, via CRISPR activation (CRISPRa), activate tomato plant defense genes to confer resistance against pathogen attack. We provide evidence that edited tomato plants for the PATHOGENESIS-RELATED GENE 1 gene (SlPR-1) show enhanced disease resistance to Clavibacter michiganensis subsp. michiganensis infection. Resistance was assessed by evaluating disease progression and symptom appearance, pathogen accumulation, and changes in SlPR-1 gene expression at different time points. We determined that CRISPRa-edited plants develop enhanced disease-resistant to the pathogen without altering their agronomic characteristics and, above all, preventing the advancement of disease symptoms, stem canker, and plant death.


Assuntos
Solanum lycopersicum , Ativação Transcricional , Clavibacter/genética , Sistemas CRISPR-Cas , Edição de Genes , Produtos Agrícolas/genética , Doenças das Plantas/genética
11.
J Plant Res ; 125(5): 679-92, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22438063

RESUMO

Polycomb group (PcG) and trithorax group (trxG) proteins are key regulators of homeotic genes and have central roles in cell proliferation, growth and development. In animals, PcG and trxG proteins form higher order protein complexes that contain SET domain proteins with histone methyltransferase activity, and are responsible for the different types of lysine methylation at the N-terminal tails of the core histone proteins. However, whether H3K4 methyltransferase complexes exist in Arabidopsis thaliana remains unknown. Here, we make use of the yeast two-hybrid system and the bimolecular fluorescence complementation assay to provide evidence for the self-association of the Arabidopsis thaliana SET-domain-containing protein SET DOMAIN GROUP 26 (SDG26), also known as ABSENT, SMALL, OR HOMEOTIC DISCS 1 HOMOLOG 1 (ASHH1). In addition, we show that the ASHH1 protein associates with SET-domain-containing sequences from two distinct histone lysine methyltransferases, the ARABIDOPSIS HOMOLOG OF TRITHORAX-1 (ATX1) and ASHH2 proteins. Furthermore, after screening a cDNA library we found that ASHH1 interacts with two proteins from the heat shock protein 40 kDa (Hsp40/DnaJ) superfamily, thus connecting the epigenetic network with a system sensing external cues. Our findings suggest that trxG complexes in Arabidopsis thaliana could involve different sets of histone lysine methyltransferases, and that these complexes may be engaged in multiple developmental processes in Arabidopsis.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Proteínas de Choque Térmico/metabolismo , Histona-Lisina N-Metiltransferase/metabolismo , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Proteínas de Arabidopsis/genética , Sequência de Bases , Regulação da Expressão Gênica de Plantas , Genes Homeobox , Histona-Lisina N-Metiltransferase/genética , Técnicas do Sistema de Duplo-Híbrido
12.
Front Oncol ; 12: 1018137, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36419896

RESUMO

Several biological processes related to cancer malignancy are regulated by 17-ß estradiol (E2) in ER+-breast cancer. To establish the role of E2 on the atypical cancer energy metabolism, a systematic study analyzing transcription factors, proteins, and fluxes associated with energy metabolism was undertaken in multicellular tumor spheroids (MCTS) from human ER+ MCF-7 breast cancer cells. At E2 physiological concentrations (10 and 100 nM for 24 h), both ERα and ERß receptors, and their protein target pS2, increased by 0.6-3.5 times vs. non-treated MCTS, revealing an activated E2/ER axis. E2 also increased by 30-470% the content of several transcription factors associated to mitochondrial biogenesis and oxidative phosphorylation (OxPhos) (p53, PGC1-α) and glycolytic pathways (HIF1-α, c-MYC). Several OxPhos and glycolytic proteins (36-257%) as well as pathway fluxes (48-156%) significantly increased being OxPhos the principal ATP cellular supplier (>75%). As result of energy metabolism stimulation by E2, cancer cell migration and invasion processes and related proteins (SNAIL, FN, MM-9) contents augmented by 24-189% vs. non-treated MCTS. Celecoxib at 10 nM blocked OxPhos (60%) as well as MCTS growth, cell migration and invasiveness (>40%); whereas the glycolytic inhibitor iodoacetate (0.5 µM) and doxorubicin (70 nM) were innocuous. Our results show for the first time using a more physiological tridimensional cancer model, resembling the initial stages of solid tumors, that anti-mitochondrial therapy may be useful to deter hormone-dependent breast carcinomas.

13.
J Cell Biochem ; 112(10): 2703-15, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21678471

RESUMO

In last decades, the basic, clinical, and translational research efforts have been directed to the identification of standard biomarkers associated with the degree of malignancy. There is an increasingly public health concern for earlier detection of cancer development at stages in which successful treatments can be achieved. To meet this urgent clinical demand, early stage cancer biomarkers supported by reliable and robust experimental data that can be readily applicable in the clinical practice, are required. In the current standard protocols, when one or two of the canonical proliferating index biomarkers are analyzed, contradictory results are frequently reached leading to incorrect cancer diagnostic and unsuccessful therapies. Therefore, the identification of other cellular characteristics or signatures present in the tumor cells either alone or in combination with the well-established proliferation markers emerge as an alternative strategy in the improvement of cancer diagnosis and treatment. Because it is well known that several pathways and processes are altered in tumor cells, the concept of "single marker" in cancer results incorrect. Therefore, this review aims to analyze and discuss the proposal that the molecular profile of different genes or proteins in different altered tumor pathways must be established to provide a better global clinical pattern for cancer detection and prognosis.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias/metabolismo , Humanos , Neoplasias/diagnóstico , Neoplasias/patologia , Prognóstico , Transdução de Sinais/fisiologia
14.
Rev Invest Clin ; 63(6): 665-702, 2011.
Artigo em Espanhol | MEDLINE | ID: mdl-23650680

RESUMO

INTRODUCTION: Ovarian cancer (OC) is the third most common gynecologic malignancy worldwide. Most of cases it is of epithelial origin. At the present time there is not a standardized screening method, which makes difficult the early diagnosis. The 5-year survival is 90% for early stages, however most cases present at advanced stages, which have a 5-year survival of only 5-20%. GICOM collaborative group, under the auspice of different institutions, have made the following consensus in order to make recommendations for the diagnosis and management regarding to this neoplasia. MATERIAL AND METHODS: The following recommendations were made by independent professionals in the field of Gynecologic Oncology, questions and statements were based on a comprehensive and systematic review of literature. It took place in the context of a meeting of two days in which a debate was held. These statements are the conclusions reached by agreement of the participant members. RESULTS: No screening method is recommended at the time for the detection of early lesions of ovarian cancer in general population. Staging is surgical, according to FIGO. In regards to the pre-surgery evaluation of the patient, it is recommended to perform chest radiography and CT scan of abdomen and pelvis with IV contrast. According to the histopathology of the tumor, in order to consider it as borderline, the minimum percentage of proliferative component must be 10% of tumor's surface. The recommended standardized treatment includes primary surgery for diagnosis, staging and cytoreduction, followed by adjuvant chemotherapy Surgery must be performed by an Oncologist Gynecologist or an Oncologist Surgeon because inadequate surgery performed by another specialist has been reported in 75% of cases. In regards to surgery it is recommended to perform total omentectomy since subclinic metastasis have been documented in 10-30% of all cases, and systematic limphadenectomy, necessary to be able to obtain an adequate surgical staging. Fertility-sparing surgery will be performed in certain cases, the procedure should include a detailed inspection of the contralateral ovary and also negative for malignancy omentum and ovary biopsy. Until now, laparoscopy for diagnostic-staging surgery is not well known as a recommended method. The recommended chemotherapy is based on platin and taxanes for 6 cycles, except in Stage IA, IB and grade 1, which have a good prognosis. In advanced stages, primary cytoreduction is recommended as initial treatment. Minimal invasion surgery is not a recommended procedure for the treatment of advanced ovarian cancer. Radiotherapy can be used to palliate symptoms. Follow up of the patients every 2-4 months for 2 years, every 3-6 months for 3 years and anually after the 5th year is recommended. Evaluation of quality of life of the patient must be done periodically. CONCLUSIONS: In the present, there is not a standardized screening method. Diagnosis in early stages means a better survival. Standardized treatment includes primary surgery with the objective to perform an optimal cytoreduction followed by chemotherapy Treatment must be individualized according to each patient. Radiotherapy can be indicated to palliate symptoms.


Assuntos
Neoplasias Ovarianas , Assistência ao Convalescente , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Quimioterapia Adjuvante , Terapia Combinada , Resistencia a Medicamentos Antineoplásicos , Diagnóstico Precoce , Feminino , Genes Neoplásicos , Humanos , Laparoscopia , Excisão de Linfonodo , Terapia Neoadjuvante , Estadiamento de Neoplasias/normas , Síndromes Neoplásicas Hereditárias/genética , Omento/cirurgia , Compostos Organoplatínicos/administração & dosagem , Neoplasias Ovarianas/diagnóstico , Neoplasias Ovarianas/epidemiologia , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia , Neoplasias Ovarianas/terapia , Ovariectomia/métodos , Cuidados Paliativos , Qualidade de Vida , Radioterapia Adjuvante , Terapia de Salvação , Taxoides/administração & dosagem
15.
Front Plant Sci ; 12: 765292, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34745196

RESUMO

Coffea spp. are tropical plants used for brewing beverages from roasted and grounded seeds, the favorite drink in the world. It is the most important commercial crop plant and the second most valuable international commodity after oil. Global coffee trade relies on two Coffea species: C. arabica L. (arabica coffee) comprising 60% and C. canephora (robusta) comprising the remaining 40%. Arabica coffee has lower productivity and better market price than robusta. Arabica coffee is threatened by disease (i.e., coffee leaf rust), pests [i.e., Hypothenemus hampei or coffee berry borer (CBB) and nematodes], and susceptibility to climate change (i.e., drought and aluminum toxicity). Plant biotechnology by means of tissue culture inducing somatic embryogenesis (SE) process, genetic transformation, and genome editing are tools that can help to solve, at least partially, these problems. This work is the continuation of a protocol developed for stable genetic transformation and successful plant regeneration of arabica coffee trees expressing the Bacillus thuringiensis (Bt) toxin Cry10Aa to induce CBB resistance. A highly SE line with a high rate of cell division and conversion to plants with 8-month plant regeneration period was produced. To validate this capability, gene expression analysis of master regulators of SE, such as BABY BOOM (BBM), FUS3, and LEC1, embryo development, such as EMB2757, and cell cycle progression, such as ETG1 and MCM4, were analyzed during induction and propagation of non-competent and highly competent embryogenic lines. The particle bombardment technique was used to generate stable transgenic lines after 3 months under selection using hygromycin as selectable marker, and 1 month in plant regeneration. Transgenic trees developed fruits after 2 years and demonstrated expression of the Bt toxin ranging from 3.25 to 13.88 µg/g fresh tissue. Bioassays with transgenic fruits on CBB first instar larvae and adults induced mortalities between 85 and 100% after 10 days. In addition, transgenic fruits showed a seed damage lower than 9% compared to 100% of control fruits and adult mortality. This is the first report on stable transformation and expression of the Cry10Aa protein in coffee plants with the potential to control CBB.

16.
Plants (Basel) ; 10(5)2021 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-33925316

RESUMO

Potato microtuber productions through in vitro techniques are ideal propagules for producing high quality seed potatoes. Microtuber development is influenced by several factors, i.e., high content sucrose and cytokinins are among them. To understand a molecular mechanism of microtuberization using osmotic stress and cytokinin signaling will help us to elucidate this process. We demonstrate in this work a rapid and efficient protocol for microtuber development and gene expression analysis. Medium with high content of sucrose and gelrite supplemented with 2iP as cytokinin under darkness condition produced the higher quantity and quality of microtubers. Gene expression analysis of genes involved in the two-component signaling system (StHK1), cytokinin signaling, (StHK3, StHP4, StRR1) homeodomains (WUSCHEL, POTH1, BEL5), auxin signaling, ARF5, carbon metabolism (TPI, TIM), protein synthesis, NAC5 and a morphogenetic regulator of tuberization (POTH15) was performed by qPCR real time. Differential gene expression was observed during microtuber development. Gene regulation of two component and cytokinin signaling is taking place during this developmental process, yielding more microtubers. Further analysis of each component is required to elucidate it.

17.
Materials (Basel) ; 14(21)2021 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-34771875

RESUMO

In this paper, the analysis, synthesis and characterization of thin films of a-Si:H deposited by PECVD were carried out. Three types of films were deposited: In the first series (00 process), an intrinsic a-Si:H film was doped. In the second series (A1-A5 process), n-type samples were doped, and to carry this out, a gas mixture of silane (SiH4), dihydrogen (H2) and phosphine (PH3) was used. In the third series (B1-B5 process), p-type samples were doped using a mixture of silane (SiH4), dihydrogen (H2) and diborane (B2H6). The films' surface morphology was characterized by atomic force microscopy (AFM), while the analysis of the films was performed by scanning electron microscopy (SEM), and UV-visible ellipsometry was used to obtain the optical band gap and film thickness. According to the results of the present study, it can be concluded that the best conditions can be obtained when the flow of dopant gases (phosphine or diborane) increases, as seen in the conductivity graphs, where the films with the highest flow of dopant gas reached the highest conductivities compared to the minimum required for materials made of a-Si:H silicon for high-quality solar cells. It can be concluded from the results that the magnitude of the conductivity, which increased by several orders, represents an important result, since we could improve the efficiency of solar cells based on a-Si:H.

18.
Front Oncol ; 11: 697408, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34414111

RESUMO

Under dysbiosis, a gut metabolic disorder, short-chain carboxylic acids (SCCAs) are secreted to the lumen, affecting colorectal cancer (CRC) development. Butyrate and propionate act as CRC growth inhibitors, but they might also serve as carbon source. In turn, the roles of acetate as metabolic fuel and protein acetylation promoter have not been clearly elucidated. To assess whether acetate favors CRC growth through active mitochondrial catabolism, a systematic study evaluating acetate thiokinase (AcK), energy metabolism, cell proliferation, and invasiveness was performed in two CRC cell lines incubated with physiological SCCAs concentrations. In COLO 205, acetate (+glucose) increased the cell density (50%), mitochondrial protein content (3-10 times), 2-OGDH acetylation, and oxidative phosphorylation (OxPhos) flux (36%), whereas glycolysis remained unchanged vs. glucose-cultured cells; the acetate-induced OxPhos activation correlated with a high AcK activity, content, and acetylation (1.5-6-fold). In contrast, acetate showed no effect on HCT116 cell growth, OxPhos, AcK activity, protein content, and acetylation. However, a substantial increment in the HIF-1α content, HIF-1α-glycolytic protein targets (1-2.3 times), and glycolytic flux (64%) was observed. Butyrate and propionate decreased the growth of both CRC cells by impairing OxPhos flux through mitophagy and mitochondrial fragmentation activation. It is described, for the first time, the role of acetate as metabolic fuel for ATP supply in CRC COLO 205 cells to sustain proliferation, aside from its well-known role as protein epigenetic regulator. The level of AcK determined in COLO 205 cells was similar to that found in human CRC biopsies, showing its potential role as metabolic marker.

19.
Cancer Manag Res ; 13: 6689-6703, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34471383

RESUMO

Cisplatin is the standard of treatment for squamous cell carcinoma of the head and neck (SCCHN) that has demonstrated efficacy, either in locally advanced disease when combined with radiotherapy at high doses, or in metastatic/recurrent disease when combined with other agents. However, the usual toxicities related to cisplatin, such as neurotoxicity, nephrotoxicity, ototoxicity, and hematologic toxicities, especially when high doses have been administered, have important implications in the patients' quality of life. The decision to administer cisplatin depends on several patient factors, such as age, performance status, weight loss, comorbidities, previous toxicities, chronic viral infection, or even the current SARS-CoV-2 pandemic. In order to establish recommendations for the management of patients with SCCHN, a group of experts in medical and radiation oncology from Spain and Latin-American discussed how to identify patients who are not candidates for cisplatin to offer them the most suitable therapeutic alternative.

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