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1.
PLoS Biol ; 22(1): e3002450, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38289899

RESUMO

Biological processes are intrinsically noisy, and yet, the result of development-like the species-specific size and shape of organs-is usually remarkably precise. This precision suggests the existence of mechanisms of feedback control that ensure that deviations from a target size are minimized. Still, we have very limited understanding of how these mechanisms operate. Here, we investigate the problem of organ size precision using the Drosophila eye. The size of the adult eye depends on the rates at which eye progenitor cells grow and differentiate. We first find that the progenitor net growth rate results from the balance between their proliferation and apoptosis, with this latter contributing to determining both final eye size and its variability. In turn, apoptosis of progenitor cells is hampered by Dpp, a BMP2/4 signaling molecule transiently produced by early differentiating retinal cells. Our genetic and computational experiments show how the status of retinal differentiation is communicated to progenitors through the differentiation-dependent production of Dpp, which, by adjusting the rate of apoptosis, exerts a feedback control over the net growth of progenitors to reduce final eye size variability.


Assuntos
Proteínas de Drosophila , Drosophila , Animais , Drosophila/genética , Drosophila melanogaster , Proteínas de Drosophila/genética , Tamanho do Órgão , Retroalimentação , Olho , Retina , Apoptose/genética
2.
Dev Cell ; 57(13): 1661-1675.e7, 2022 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-35716661

RESUMO

Recruitment of stem cells is crucial for tissue repair. Although stem cell niches can provide important signals, little is known about mechanisms that coordinate the engagement of disseminated stem cells across an injured tissue. In Drosophila, adult brain lesions trigger local recruitment of scattered dormant neural stem cells suggesting a mechanism for creating a transient stem cell activation zone. Here, we find that injury triggers a coordinated response in neuro-glial clusters that promotes the spread of a neuron-derived stem cell factor via glial secretion of the lipocalin-like transporter Swim. Strikingly, swim is induced in a Hif1-α-dependent manner in response to brain hypoxia. Mammalian Swim (Lcn7) is also upregulated in glia of the mouse hippocampus upon brain injury. Our results identify a central role of neuro-glial clusters in promoting neural stem cell activation at a distance, suggesting a conserved function of the HIF1-α/Swim/Wnt module in connecting injury-sensing and regenerative outcomes.


Assuntos
Drosophila , Células-Tronco Neurais , Animais , Mamíferos , Camundongos , Neuroglia , Neurônios , Nicho de Células-Tronco
4.
Arq. Asma, Alerg. Imunol ; 5(2): 203-207, abr.jun.2021. ilus
Artigo em Inglês | LILACS | ID: biblio-1398933

RESUMO

Allergy to persimmon (Diospyros kaki ) has been only rarely reported. The antigenic composition of the fruit is not entirely known. Thaumatin-like proteins (TLPs) have been described as allergens in pollens and various fruits, such as kiwi and banana, but not in persimmon. We report the case of a 22-year-old man, with persistent moderate-to-severe allergic rhinitis, sensitized to house dust mites. The patient describes an episode of oral mucosa and ear canal pruritus, followed by diffuse urticaria, which rapidly evolved to dysphonia, dyspnea, and dizziness, after eating raw persimmon. A few months later he developed similar cutaneous symptoms accompanied by nausea, vomiting, abdominal colic, and hypotension immediately after the intake of banana. The prick-prick test with raw persimmon and banana were positive, as well as the serum specific IgE to the extract of these fruits. The ImmunoCAP ISAC_112i test demonstrated a positive specific IgE against Act d 2 (kiwi thaumatin), which is homologous to banana TLP (Mus a 4). Serum IgE inhibition test with "sponge" of Diospyros kaki ImmunoCAP (f301) showed partial inhibition (40%) of IgE to Act d 2. This raises the suspicion that a TLP is at least partially responsible for the referred sensitization. This patient is sensitized to Diospyros kaki and Musa acuminata. An anaphylactic reaction to consumed persimmon, presumably as a result from cross-allergy with banana thaumatin was diagnosed in our patient. Thaumatin has not been previously described as an allergen of persimmon with cross-reactivity with banana, and in vitro with Act d 2 (kiwi TLP).


A alergia ao caqui (Diospyros kaki ) tem sido raramente documentada, não sendo a composição antigênica da fruta totalmente conhecida. Proteínas semelhantes à taumatina (TLPs) foram descritas como alergênicos em pólens e várias frutas, como no kiwi e banana, mas não no caqui. Apresenta-se o caso de um doente de 22 anos, com rinite alérgica persistente moderadagrave, sensibilizado a ácaros do pó doméstico. O doente refere episódio de prurido na mucosa oral e canal auditivo, seguido de urticária generalizada, que rapidamente evoluiu para disfonia, dispneia e tontura, após ingestão de caqui. Poucos meses depois, desenvolveu sintomas cutâneos semelhantes, acompanhados de náuseas, vómitos, cólica abdominal e hipotensão imediatamente após ingestão de uma banana. O teste cutâneo por picada com caqui e banana em natureza foram positivos, bem como o doseamento de IgE específica. O teste ImmunoCAP ISAC_112i identificou a presença de IgE específica para Act d 2 (taumatina do kiwi), homóloga da TLP da banana (Mus a 4). O estudo de inibição ImmunoCAP ISAC com "esponja" de Diospyros kaki (f301) produziu uma inibição parcial (40%) da ligação de IgE a Act d 2, permitindo presumir que uma proteína semelhante à taumatina é, pelo menos, parcialmente responsável pela referida sensibilização. Este doente encontra-se sensibilizado a Diospyros kaki e Musa acuminata. Uma anafilaxia ao caqui ingerido, presumivelmente resultante de reatividade cruzada com a taumatina da banana foi diagnosticada. Não estão descritas na literatura TLPs como alergênicos do caqui com reatividade cruzada com a banana e com Act d 2 in vitro (TLP do kiwi).


Assuntos
Humanos , Masculino , Adulto Jovem , Diospyros , Musa , Ingestão de Alimentos , Rinite Alérgica , Frutas , Hipersensibilidade , Anafilaxia , Ácaros , Prurido , Sinais e Sintomas , Urticária , Vômito , Imunoglobulina E , Testes Intradérmicos , Alérgenos , Cólica , Meato Acústico Externo , Mucosa Bucal , Náusea
5.
Nat Aging ; 1(8): 666-676, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-37117767

RESUMO

The gut microbiota is increasingly recognized as an important regulator of host immunity and brain health. The aging process yields dramatic alterations in the microbiota, which is linked to poorer health and frailty in elderly populations. However, there is limited evidence for a mechanistic role of the gut microbiota in brain health and neuroimmunity during aging processes. Therefore, we conducted fecal microbiota transplantation from either young (3-4 months) or old (19-20 months) donor mice into aged recipient mice (19-20 months). Transplant of a microbiota from young donors reversed aging-associated differences in peripheral and brain immunity, as well as the hippocampal metabolome and transcriptome of aging recipient mice. Finally, the young donor-derived microbiota attenuated selective age-associated impairments in cognitive behavior when transplanted into an aged host. Our results reveal that the microbiome may be a suitable therapeutic target to promote healthy aging.


Assuntos
Microbioma Gastrointestinal , Microbiota , Animais , Camundongos , Transplante de Microbiota Fecal , Envelhecimento/genética , Encéfalo
6.
Arq. Asma, Alerg. Imunol ; 4(4): 480-486, out.dez.2020. ilus
Artigo em Inglês | LILACS | ID: biblio-1382072

RESUMO

Kounis syndrome is described as the occurrence of myocardial injury following a hypersensitivity reaction triggered by allergen exposure. The actual incidence is unknown, as most of the information comes from case reports and there are no international recommendations. Kounis syndrome does not seem to be rare but rather underdiagnosed. We report and discuss the clinical presentation and management of 4 cases of Kounis syndrome. All patients presented with anaphylaxis and chest pain. Patient age ranged from 44 to 83 years. Anaphylaxis triggers were nonsteroidal anti-inflammatory drugs and antibiotics. It is important to recognize Kounis syndrome in order to conduct an adequate investigation and prevent further events. A major difficulty is that the treatment of the 2 entities (hypersensitivity reaction and acute coronary syndrome) may worsen each other. Large prospective studies are needed to establish definitive treatment guidelines for these patients.


A síndrome de Kounis caracteriza-se pela ocorrência de uma síndrome coronária aguda no contexto de uma reação alérgica concomitante desencadeada por exposição a um alergênio. A sua incidência real é desconhecida e não há consenso relativamente à abordagem, uma vez que a maioria dos dados provem de relatos de casos. A síndrome de Kounis não parece ser uma entidade rara, mas é infrequentemente diagnosticada. Apresentamos quatro casos, a sua apresentação clínica e abordagem diagnóstica e terapêutica. Todos os doentes, com idades entre os 44 e os 83 anos, se apresentaram com anafilaxia e dor torácica. Os fatores desencadeantes foram fármacos: anti-inflamatórios não esteroides e antibióticos. Torna-se importante reconhecer a síndrome de Kounis, de modo a que possa ser feita investigação adequada e prevenidos novos eventos. A grande dificuldade reside no fato de que o tratamento das duas entidades (Reação de hipersensibilidade e Síndrome coronária aguda), pode agravar uma à outra. São necessários estudos prospetivos alargados de modo a estabelecer diretrizes definitivas para o tratamento destes doentes.


Assuntos
Humanos , Adulto , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Alérgenos , Hipersensibilidade a Drogas , Síndrome Coronariana Aguda , Síndrome de Kounis , Anafilaxia , Pacientes , Terapêutica , Fatores Desencadeantes , Anti-Inflamatórios não Esteroides , Antibacterianos
7.
Nutrients ; 12(9)2020 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-32932733

RESUMO

Blueberry (BB) consumption is linked to improved health. The bioconversion of the polyphenolic content of BB by fermentative bacteria in the large intestine may be a necessary step for the health benefits attributed to BB consumption. The identification of specific gut microbiota taxa that respond to BB consumption and that mediate the bioconversion of consumed polyphenolic compounds into bioactive forms is required to improve our understanding of how polyphenols impact human health. We tested the ability of polyphenol-rich fractions purified from whole BB-namely, anthocyanins/flavonol glycosides (ANTH/FLAV), proanthocyanidins (PACs), the sugar/acid fraction (S/A), and total polyphenols (TPP)-to modulate the fecal microbiota composition of healthy adults in an in vitro colon system. In a parallel pilot study, we tested the effect of consuming 38 g of freeze-dried BB powder per day for 6 weeks on the fecal microbiota of 17 women in two age groups (i.e., young and older). The BB ingredients had a distinct effect on the fecal microbiota composition in the artificial colon model. The ANTH/FLAV and PAC fractions were more effective in promoting microbiome alpha diversity compared to S/A and TPP, and these effects were attributed to differentially responsive taxa. Dietary enrichment with BB resulted in a moderate increase in the diversity of the microbiota of the older subjects but not in younger subjects, and certain health-relevant taxa were significantly associated with BB consumption. Alterations in the abundance of some gut bacteria correlated not only with BB consumption but also with increased antioxidant activity in blood. Collectively, these pilot data support the notion that BB consumption is associated with gut microbiota changes and health benefits.


Assuntos
Mirtilos Azuis (Planta)/química , Microbioma Gastrointestinal/efeitos dos fármacos , Polifenóis/farmacologia , Adulto , Idoso , Antocianinas/farmacologia , Antioxidantes/metabolismo , Colo/microbiologia , Fezes/microbiologia , Feminino , Fermentação , Flavonóis/farmacologia , Glicosídeos/farmacologia , Voluntários Saudáveis , Humanos , Modelos Anatômicos , Estresse Oxidativo/efeitos dos fármacos , Projetos Piloto , Adulto Jovem
8.
Gut ; 69(7): 1218-1228, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32066625

RESUMO

OBJECTIVE: Ageing is accompanied by deterioration of multiple bodily functions and inflammation, which collectively contribute to frailty. We and others have shown that frailty co-varies with alterations in the gut microbiota in a manner accelerated by consumption of a restricted diversity diet. The Mediterranean diet (MedDiet) is associated with health. In the NU-AGE project, we investigated if a 1-year MedDiet intervention could alter the gut microbiota and reduce frailty. DESIGN: We profiled the gut microbiota in 612 non-frail or pre-frail subjects across five European countries (UK, France, Netherlands, Italy and Poland) before and after the administration of a 12-month long MedDiet intervention tailored to elderly subjects (NU-AGE diet). RESULTS: Adherence to the diet was associated with specific microbiome alterations. Taxa enriched by adherence to the diet were positively associated with several markers of lower frailty and improved cognitive function, and negatively associated with inflammatory markers including C-reactive protein and interleukin-17. Analysis of the inferred microbial metabolite profiles indicated that the diet-modulated microbiome change was associated with an increase in short/branch chained fatty acid production and lower production of secondary bile acids, p-cresols, ethanol and carbon dioxide. Microbiome ecosystem network analysis showed that the bacterial taxa that responded positively to the MedDiet intervention occupy keystone interaction positions, whereas frailty-associated taxa are peripheral in the networks. CONCLUSION: Collectively, our findings support the feasibility of improving the habitual diet to modulate the gut microbiota which in turn has the potential to promote healthier ageing.


Assuntos
Dieta Mediterrânea , Fragilidade/prevenção & controle , Microbioma Gastrointestinal , Idoso , Europa (Continente) , Feminino , Fragilidade/dietoterapia , Microbioma Gastrointestinal/genética , Nível de Saúde , Humanos , Masculino , Cooperação do Paciente , RNA Ribossômico 16S/genética , Método Simples-Cego
9.
Lisboa; s.n; 2020.
Tese em Português | BDENF - Enfermagem | ID: biblio-1372816

RESUMO

A excelência dos cuidados em enfermagem pediátrica tem como fio condutor o bem-estar da criança, visando sempre a maximização da sua saúde e a adaptação a situações relacionadas com o ciclo de vida ou com uma condição de saúde complexa. Enquanto requisitos da humanização desses cuidados importa realçar os cuidados centrados na família, os cuidados não traumáticos e a parceria de cuidados, numa estreita relação com uma abordagem holística e multidisciplinar que visa dar a resposta mais adequada às necessidades de cada criança e família. Cuidar com vista ao bem-estar tem intrínseco a gestão diferenciada da dor enquanto aspeto crucial a ser considerado. Recorrendo ao modelo de sistemas de Neuman enquanto quadro de referência orientador da prática, a dor é identificada enquanto stressor que pode interferir com o bem-estar da criança e família, sendo o controlo da mesma reconhecido enquanto direito, mas ainda considerado uma meta a alcançar. Intervir nesta área implica articular a melhor evidência com as estratégias definidas como prioritárias para melhorar os cuidados referentes ao controlo da dor, nomeadamente o desenvolvimento de modelos de boas práticas, a formação dos profissionais e a literacia da população. Outro aspeto a salientar relaciona-se com a necessidade de consistência e articulação entre o reconhecimento da presença de dor, a implementação de intervenções, a reavaliação e o registo, numa abordagem individualizada e interdisciplinar. O presente relatório pretende refletir o percurso realizado com vista ao desenvolvimento de competências de mestre e de enfermeiro especialista que possibilitam a prestação de cuidados de nível avançado na área da saúde infantil e pediatria. Tem como particular enfoque o controlo da dor da criança, essencialmente no contexto da anemia das células falciformes onde a dor assume uma especial relevância e a sua gestão algumas particularidades. A metodologia envolveu a concretização de um Estágio em diferentes contextos, que permitiu articular teoria e prática, assente sempre numa reflexão crítica contínua das aprendizagens realizadas.


Excellence in pediatric nursing care is guided by the child's well-being, always aiming at maximizing their health and adapting to situations of the life cycle or any complex health condition. To provide such humanistic care it is important to highlight family-centered care, non-traumatic care and partnership in care, in a close relationship with a holistic and multidisciplinary approach that aims to provide the most appropriate response to the needs of each child and family. Differentiated pain management is intrinsic to care and a crucial aspect to consider. According to the Neuman systems model, adopted as reference for practice, pain is identified as a stressor that can interfere with the well-being of the child and family, with its management recognized as a right, and a goal to be achieved. Intervention in this area implies articulating the best evidence with the priority strategies defined to improve care related to pain control, namely the development of models of good practices, the training of professionals and the literacy of the population. Another aspect to be highlighted relates to the need for consistency and articulation between the recognition of the presence of pain, the implementation of interventions, reevaluation and documentation, in an individualized and interdisciplinary approach. This report aims to reflect the path taken to develop the competencies of master and specialist nurse that enable the provision of advanced care in the area of child health and pediatrics. Its particular focus is management of pain in the child, namely in the context of sickle cell disease where pain assumes a special relevance and its control some particularities. The methodology involved the realization of a clinical placement in different settings that allowed the articulation of theory and practice, always based on a continuous critical reflection of the lessons learned.


Assuntos
Humanos , Criança , Enfermagem Pediátrica , Criança , Manejo da Dor , Manejo da Dor/enfermagem , Anemia Falciforme , Anemia Falciforme/enfermagem , Família
10.
Sci Rep ; 7(1): 4845, 2017 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-28687780

RESUMO

The specification and growth of organs is controlled simultaneously by networks of transcription factors. While the connection between these transcription factors with fate determinants is increasingly clear, how they establish the link with the cell cycle is far less understood. Here we investigate this link in the developing Drosophila eye, where two transcription factors, the MEIS1 homologue hth and the Zn-finger tsh, synergize to stimulate the proliferation of naïve eye progenitors. Experiments combining transcriptomics, open-chromatin profiling, motif analysis and functional assays indicate that these progenitor transcription factors exert a global regulation of the proliferation program. Rather than directly regulating cell cycle genes, they control proliferation through an intermediary layer of nuclear receptors of the ecdysone/estrogen-signaling pathway. This regulatory subnetwork between hth, tsh and nuclear receptors might be conserved from Drosophila to mammals, as we find a significant co-overexpression of their human homologues in specific cancer types.


Assuntos
Pontos de Checagem do Ciclo Celular , Proteínas de Drosophila/metabolismo , Drosophila/embriologia , Proteínas de Homeodomínio/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Proteínas Repressoras/metabolismo , Animais , Proliferação de Células , Cromatina/metabolismo , Olho/embriologia , Perfilação da Expressão Gênica , Transdução de Sinais
11.
ISME J ; 11(9): 2059-2074, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28585938

RESUMO

The biological significance of Archaea in the human gut microbiota is largely unclear. We recently reported genomic and biochemical analyses of the Methanomassiliicoccales, a novel order of methanogenic Archaea dwelling in soil and the animal digestive tract. We now show that these Methanomassiliicoccales are present in published microbiome data sets from eight countries. They are represented by five Operational Taxonomic Units present in at least four cohorts and phylogenetically distributed into two clades. Genes for utilizing trimethylamine (TMA), a bacterial precursor to an atherosclerogenic human metabolite, were present in four of the six novel Methanomassiliicoccales genomes assembled from ELDERMET metagenomes. In addition to increased microbiota TMA production capacity in long-term residential care subjects, abundance of TMA-utilizing Methanomassiliicoccales correlated positively with bacterial gene count for TMA production and negatively with fecal TMA concentrations. The two large Methanomassiliicoccales clades have opposite correlations with host health status in the ELDERMET cohort and putative distinct genomic signatures for gut adaptation.


Assuntos
Archaea/genética , Archaea/metabolismo , Microbioma Gastrointestinal , Metilaminas/metabolismo , Idoso , Idoso de 80 Anos ou mais , Animais , Archaea/classificação , Archaea/isolamento & purificação , Fezes/microbiologia , Feminino , Trato Gastrointestinal/microbiologia , Genômica , Humanos , Masculino , Metagenoma , Metagenômica , Microbiota , Filogenia
12.
Dev Biol ; 418(1): 98-107, 2016 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-27502436

RESUMO

During organ development, the progenitor state is transient, and depends on specific combinations of transcription factors and extracellular signals. Not surprisingly, abnormal maintenance of progenitor transcription factors may lead to tissue overgrowth, and the concurrence of signals from the local environment is often critical to trigger this overgrowth. Therefore, identifying specific combinations of transcription factors/signals promoting -or opposing- proliferation in progenitors is essential to understand normal development and disease. We have investigated this issue using the Drosophila eye as model. Transcription factors hth and tsh are transiently expressed in eye progenitors causing the expansion of the progenitor pool. However, if their co-expression is maintained experimentally, cell proliferation continues and differentiation is halted. Here we show that Hth+Tsh-induced tissue overgrowth requires the BMP2 Dpp and the abnormal hyperactivation of its pathway. Rather than using autocrine Dpp expression, Hth+Tsh cells increase their avidity for Dpp, produced locally, by upregulating extracellular matrix components. During normal development, Dpp represses hth and tsh ensuring that the progenitor state is transient. However, cells in which Hth+Tsh expression is forcibly maintained use Dpp to enhance their proliferation.


Assuntos
Olho Composto de Artrópodes/embriologia , Proteínas de Drosophila/biossíntese , Proteínas de Drosophila/metabolismo , Drosophila/embriologia , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Homeodomínio/biossíntese , Proteínas Repressoras/biossíntese , Animais , Diferenciação Celular/genética , Proliferação de Células/genética , Olho Composto de Artrópodes/citologia , Proteínas de Drosophila/genética , Proteínas de Homeodomínio/genética , Proteínas Repressoras/genética , Transdução de Sinais
13.
Appl Microbiol Biotechnol ; 99(12): 5307-16, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25666680

RESUMO

A survey in 16 activated sludge wastewater treatment plants (WWTP) was conducted to contribute to the knowledge of the environmental parameters that determine the composition of the filamentous community. A total of 128 samples of mixed liquor from municipal WWTP were collected during 2 years, and 22 filamentous morphotypes were identified. The most frequent and abundant filamentous bacteria were, in both cases and by this order, type 0041/0675, type 0092, Microthrix parvicella and 1851, nocardioforms and Haliscomenobacter hydrossis. Concerning dominance, type 1851 was the most frequently dominant morphotype, followed by M. parvicella and types 0092 and 0041/0675. These were also, and by this order, the dominant morphotypes during bulking occurrences. Significant correlations were obtained between the abundance of filamentous bacteria and environmental parameters, but multivariate statistical analysis only confirmed the correlation between type 0092 and Sludge Volume Index (SVI), emphasizing the association of this filament with bulking. The discussion of the results in light of published works was complicated by the random use of terms such as frequency, abundance, and dominance with different and often unclear meanings. This reinforces the need of clarifying these terms when discussing the causes of filamentous overgrowth in WWTP.


Assuntos
Bactérias/isolamento & purificação , Esgotos/microbiologia , Bactérias/classificação , Bactérias/genética , Ecossistema , Portugal , Esgotos/análise , Águas Residuárias/análise , Águas Residuárias/microbiologia , Purificação da Água/instrumentação , Purificação da Água/métodos
14.
Dev Biol ; 377(1): 154-65, 2013 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-23416177

RESUMO

Drosophila Decapentaplegic (Dpp), a member of the BMP2/4 class of the TGF-ßs, is required for organ growth, patterning and differentiation. However, much remains to be understood about the mechanisms acting downstream of these multiple roles. Here we investigate this issue during the development of the Drosophila eye. We have previously identified viriato (vito) as a dMyc-target gene encoding a nucleolar protein that is required for proper tissue growth in the developing eye. By carrying out a targeted in vivo double-RNAi screen to identify genes and pathways functioning with Vito during eye development, we found a strong genetic interaction between vito and members of the Dpp signaling pathway including the TGF-ß receptors tkv (type I), put (type II), and the co-Smad medea (med). Analyzing the expression of the Dpp receptor Tkv and the activation pattern of the pathway's transducer, p-Mad, we found that vito is required for a correct signal transduction in Dpp-receiving cells. Overall, we validate the use of double RNAi to find specific genetic interactions and, in particular, we uncover a link between the Dpp pathway and Vito, a nucleolar component. vito would act genetically downstream of Dpp, playing an important role in maintaining a sufficient level of Dpp activity for the promotion of eye disc growth and regulation of photoreceptor differentiation in eye development.


Assuntos
Diferenciação Celular , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/crescimento & desenvolvimento , Olho/citologia , Olho/crescimento & desenvolvimento , Proteínas Nucleares/metabolismo , Transdução de Sinais , Animais , Apoptose/genética , Padronização Corporal/genética , Diferenciação Celular/genética , Drosophila melanogaster/citologia , Drosophila melanogaster/genética , Feminino , Técnicas de Silenciamento de Genes , Genes de Insetos , Masculino , Interferência de RNA , Transdução de Sinais/genética
15.
Biotechnol J ; 4(12): 1753-65, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19844913

RESUMO

Microbial symbiosis is a ubiquitous aspect of life and was a major element in the ability of insects to explore several adverse environments. To date, the study of symbiosis in insects has been impaired by the unculturability of most symbionts. However, some molecular methods represent powerful tools to help understand insect-microorganism associations and to disclose new symbiont-host systems. Beyond playing an essential role in nutrition and development of the insects, symbionts can produce bioactive compounds that protect the host against adverse environmental conditions, predators and/or direct competitors. Since the search for natural bioactive products and new enzymes is a developing area, understanding the diversity and nature of symbiont-host relationships paves the way for the exploitation of new resources in biotechnology. Furthermore, genetic transformation of the symbionts with genes that code for compounds that are toxic for pathogenic and phytopathogenic agents is also a promising area of application of the insect-symbiont relationships. The search for new bioactive compounds, the use of symbionts for pest and disease control and the molecular strategies applied for these purposes are issues of particular interest for innovative biotechnological applications and are addressed in the present review.


Assuntos
Fenômenos Fisiológicos Bacterianos , Biotecnologia/métodos , Interações Hospedeiro-Patógeno/fisiologia , Insetos , Simbiose/fisiologia , Animais , Bactérias/patogenicidade , Expressão Gênica , Regulação da Expressão Gênica , Genoma Bacteriano , Insetos/microbiologia , Insetos/fisiologia , Controle Biológico de Vetores
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