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1.
Health Promot Int ; 29(1): 81-90, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22942273

RESUMO

This study investigated feasibility and acceptability of a new email-delivered intervention promoting fruit and vegetable consumption in a university-based population of Australian young adults. The study explored whether there are differences in the reported feasibility and acceptability between demographic groups within the population of interest and at three levels of intervention intensity. The email-delivered intervention program consists of an implementation intention 'planning task' and between 3 and 15 short email messages over a 15-day study period. The intervention program was developed using the Theory of Planned Behaviour and was designed to modify perceived behavioural control. One hundred and ten participants (mean age = 19.21 years, 25.6% male) completed the feasibility and acceptability questionnaire at Day 15. This questionnaire contained items about all intervention components. High acceptability and feasibility scores were found for all intervention parts and at all levels of intervention intensity. There were few significant differences in the reported acceptability of items between key demographic sub-groups, and no differences in reported acceptability at different levels of intervention intensity. These results suggest that this email-delivered intervention is an acceptable and feasible tool for promoting fruit and vegetable consumption for participants in the target population.


Assuntos
Correio Eletrônico , Comportamento Alimentar , Promoção da Saúde/métodos , Modelos Teóricos , Comportamento de Redução do Risco , Adolescente , Adulto , Austrália , Estudos de Viabilidade , Feminino , Frutas , Humanos , Masculino , Inquéritos e Questionários/normas , Verduras , Adulto Jovem
2.
Appetite ; 58(3): 997-1004, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22349778

RESUMO

This study evaluated the efficacy of a theory of planned behaviour (TPB) based intervention to increase fruit and vegetable consumption. The extent to which fruit and vegetable consumption and change in intake could be explained by the TPB was also examined. Participants were randomly assigned to two levels of intervention frequency matched for intervention content (low frequency n=92, high frequency n=102). Participants received TPB-based email messages designed to increase fruit and vegetable consumption, messages targeted attitude, subjective norm and perceived behavioural control (PBC). Baseline and post-intervention measures of TPB variables and behaviour were collected. Across the entire study cohort, fruit and vegetable consumption increased by 0.83 servings/day between baseline and follow-up. Intention, attitude, subjective norm and PBC also increased (p<.05). The TPB successfully modelled fruit and vegetable consumption at both time points but not behaviour change. The increase of fruit and vegetable consumption is a promising preliminary finding for those primarily interested in increasing fruit and vegetable consumption. However, those interested in theory development may have concerns about the use of this model to explain behaviour change in this context. More high quality experimental tests of the theory are needed to confirm this result.


Assuntos
Atitude Frente a Saúde , Dieta , Comportamento Alimentar , Comportamentos Relacionados com a Saúde , Promoção da Saúde/métodos , Intenção , Adolescente , Adulto , Controle Comportamental , Correio Eletrônico , Ingestão de Energia , Estudos de Avaliação como Assunto , Feminino , Frutas , Humanos , Masculino , Modelos Psicológicos , Percepção , Teoria Psicológica , Resultado do Tratamento , Verduras , Adulto Jovem
3.
J Psychosom Res ; 150: 110626, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34583017

RESUMO

OBJECTIVE: The success of COVID-19 vaccination programs relies on community attitudes, yet little is known about parents' views. We aimed to explore the reasons behind Australian parents' vaccine intentions for themselves and for their children. METHOD: This mixed methods study relates to Wave 13 (January 2021) of a longitudinal study of Australian parents' experiences during COVID-19 and contained 1094 participants (83% mothers). We used multinomial logistic regression to understand demographic predictors of vaccine intention, and a descriptive template thematic analysis to analyse open-ended questions about parents' reasons for vaccine intentions for themselves and their children. RESULTS: 64% of Australian parents intend on vaccination, 26% are unsure and 9% intend to decline; 48% intend to vaccinate their children, 38% are unsure, and 14% intend to decline. Relative to those intending to vaccinate, parents unsure (OR = -0.63, 95% CI: 0.46, -0.84, p = .002) or not intending (OR = -0.41, 95% CI: 0.24, 0.67 p < .001) to vaccinate were more likely to have lower trust in doctors. Similar predictors emerged for parents who did not intend to vaccinate their children (OR = 0.47, 95% CI: 0.31, 0.70, p < .001). Qualitative data indicated that many parents had not made a firm decision, including a lack of alignment between intentions and reasons. For example, parents who said 'yes' to vaccination, often then expressed hesitance and a focus on risks in their written response. Reasons for hesitancy for themselves included concerns about testing, side effects, and long-term outcomes. Similar themes were present for children, but parents expressed a strong desire to protect their children, and an eagerness for health information. CONCLUSION: Based on prior research and the themes identified here, a multipronged campaign that includes education/promotion, good access to vaccines and role models, is likely to support parents to make informed decisions regarding COVID-19 vaccination.


Assuntos
COVID-19 , Venenos , Austrália , Vacinas contra COVID-19 , Criança , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Intenção , Estudos Longitudinais , Pais , SARS-CoV-2 , Vacinação
4.
Ann Oncol ; 21(3): 608-614, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19880433

RESUMO

BACKGROUND: Substantial numbers of cancer patients use complementary medicine therapies, even without a supportive evidence base. This study aimed to evaluate in a randomized controlled trial, the use of Medical Qigong (MQ) compared with usual care to improve the quality of life (QOL) of cancer patients. PATIENTS AND METHODS: One hundred and sixty-two patients with a range of cancers were recruited. QOL and fatigue were measured by Functional Assessment of Cancer Therapy-General and Functional Assessment of Cancer Therapy-Fatigue, respectively, and mood status by Profile of Mood State. The inflammatory marker serum C-reactive protein (CRP) was monitored serially. RESULTS: Regression analysis indicated that the MQ group significantly improved overall QOL (t(144) = -5.761, P < 0.001), fatigue (t(153) = -5.621, P < 0.001), mood disturbance (t(122) =2.346, P = 0.021) and inflammation (CRP) (t(99) = 2.042, P < 0.044) compared with usual care after controlling for baseline variables. CONCLUSIONS: This study indicates that MQ can improve cancer patients' overall QOL and mood status and reduce specific side-effects of treatment. It may also produce physical benefits in the long term through reduced inflammation.


Assuntos
Afeto , Exercícios Respiratórios , Fadiga/terapia , Inflamação/terapia , Neoplasias/fisiopatologia , Qualidade de Vida , Adulto , Idoso , Idoso de 80 Anos ou mais , Proteína C-Reativa/metabolismo , Estudos de Casos e Controles , Feminino , Nível de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/psicologia , Avaliação de Resultados em Cuidados de Saúde , Prognóstico , Inquéritos e Questionários
5.
Bioorg Med Chem Lett ; 19(22): 6473-6, 2009 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-19818612

RESUMO

Six novel isoflavone derivatives along with four known isoflavones were isolated from a culture of a highly nickel-resistant strain of Streptomyces mirabilis from a former uranium mining area. The structures of 7-hydroxy-3',5'-dihydroxyisoflavone (5), 5,7-dihydroxy-3',5'-dihydroxyisoflavone (6), 2'-hydroxy-3'-methoxygenistein (7), as well as hydroisoflavones A-C (8-10) were elucidated by MS and NMR analyses. Compounds 8-10 feature yet unprecedented types of non-aromatic, hydroxylated B rings, which result from plant isoflavone biotransformation. All new compounds display weak cytotoxic but potent antiproliferative activities. The anti-oestrogenic properties of 8 against MCF-7 human breast cancer cell line (GI(50): 6 microM) is even higher than the reference compound genistein.


Assuntos
Anticarcinógenos/farmacologia , Antineoplásicos/uso terapêutico , Isoflavonas/uso terapêutico , Antineoplásicos/química , Antioxidantes/análise , Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Biotransformação , Células CACO-2/patologia , Carcinógenos/farmacologia , Linhagem Celular Tumoral , Cromatografia Líquida de Alta Pressão , Genisteína/análise , Genisteína/metabolismo , Genisteína/uso terapêutico , Humanos , Isoflavonas/química , Modelos Moleculares , Estresse Oxidativo/efeitos dos fármacos , Casca de Planta/química
6.
J Appl Microbiol ; 107(5): 1687-96, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19457036

RESUMO

AIMS: As a toxic metal, cadmium (Cd) affects microbial and plant metabolic processes, thereby potentially reducing the efficiency of microbe or plant-mediated remediation of Cd-polluted soil. The role of siderophores produced by Streptomyces tendae F4 in the uptake of Cd by bacteria and plant was investigated to gain insight into the influence of siderophores on Cd availability to micro-organisms and plants. METHODS AND RESULTS: The bacterium was cultured under siderophore-inducing conditions in the presence of Cd. The kinetics of siderophore production and identification of the siderophores and their metal-bound forms were performed using electrospray ionization mass spectrometry. Inductively coupled plasma spectroscopy was used to measure iron (Fe) and Cd contents in the bacterium and in sunflower plant grown in Cd-amended soil. Siderophores significantly reduced the Cd uptake by the bacterium, while supplying it with iron. Bacterial culture filtrates containing three hydroxamate siderophores secreted by S. tendae F4 significantly promoted plant growth and enhanced uptake of Cd and Fe by the plant, relative to the control. Furthermore, application of siderophores caused slightly more Cd, but similar Fe uptake, compared with EDTA. Bioinoculation with Streptomyces caused a dramatic increase in plant Fe content, but resulted only in slight increase in plant Cd content. CONCLUSION: It is concluded that siderophores can help reduce toxic metal uptake in bacteria, while simultaneously facilitating the uptake of such metals by plants. Also, EDTA is not superior to hydroxamate siderophores in terms of metal solubilization for plant uptake. SIGNIFICANCE AND IMPACT OF THE STUDY: The study showed that microbial processes could indirectly influence the availability and amount of toxic metals taken up from the rhizosphere of plants. Furthermore, although EDTA is used for chelator-enhanced phytoremediation, microbial siderophores would be ideal for this purpose.


Assuntos
Cádmio/metabolismo , Helianthus/efeitos dos fármacos , Sideróforos/metabolismo , Streptomyces/metabolismo , Helianthus/química , Helianthus/crescimento & desenvolvimento , Ácidos Indolacéticos/metabolismo , Ferro/análise , Cinética , Brotos de Planta/química , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/crescimento & desenvolvimento , Sideróforos/farmacologia , Espectrometria de Massas por Ionização por Electrospray , Streptomyces/efeitos dos fármacos
7.
FEMS Microbiol Rev ; 18(1): 65-87, 1996 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8672296

RESUMO

In order to achieve genetic rearrangement in a sexual cycle, eukaryotes go through the processes of meiosis and mating. Different mating types assure that mating is only possible between two genetically diverse individuals. Basidiomycetous fungi display thousands of different mating types that are determined by two genetically unlinked loci. One locus is multiallelic and contains genes for homeodomain transcription factors which are able to form heterodimers. The activation of target genes is dependent on heterodimers formed from the monomeric transcription factor proteins originating from different alleles of this genetic locus. The interactions between the two monomeric transcription factors and the activation of target genes by the heterodimeric proteins make this regulatory system both complex and interesting. The second locus contains a pheromone receptor system: the pheromone receptor is similar to the G protein-linked serpentine receptors in Saccharomyces cerevisiae that activate the pheromone response via a phosphorylation signal transduction cascade in S. cerevisiae. This pheromone perception is a trigger of sexual development and not, as with yeast, itself under control of mating type genes. Rather it directly senses diversity at the mating type loci. Whereas heterobasidiomycetes display a bi-allelic structure for this locus with recognition between one receptor and the opposite pheromone, homobasidiomycetes contain multiple specificities for pheromone receptors and pheromones.


Assuntos
Fungos/genética , Basidiomycota/genética , Basidiomycota/crescimento & desenvolvimento , Basidiomycota/fisiologia , Evolução Biológica , Cruzamentos Genéticos , Fungos/crescimento & desenvolvimento , Fungos/fisiologia , Proteínas de Ligação ao GTP/fisiologia , Fator de Acasalamento , Meiose , Peptídeos/genética , Peptídeos/fisiologia , Feromônios/genética , Feromônios/fisiologia , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/crescimento & desenvolvimento , Saccharomyces cerevisiae/fisiologia , Schizophyllum/genética , Schizophyllum/crescimento & desenvolvimento , Schizophyllum/fisiologia , Transdução de Sinais , Fatores de Transcrição/genética , Fatores de Transcrição/fisiologia
8.
Obes Rev ; 16(5): 424-32, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25752592

RESUMO

Obesity rates have increased dramatically in recent decades, and it has proven difficult to treat. An attentional bias towards food cues may be implicated in the aetiology of obesity and influence cravings and food consumption. This review systematically investigated whether attentional biases to food cues exist in overweight/obese compared with healthy weight individuals. Electronic database were searched for relevant papers from inception to October 2014. Only studies reporting food-related attentional bias between either overweight (body mass index [BMI] 25.0-29.9 kg m(-2)) or obese (BMI ≥ 30) participants and healthy weight participants (BMI 18.5-24.9) were included. The findings of 19 studies were reported in this review. Results of the literature are suggestive of differences in attentional bias, with all but four studies supporting the notion of enhanced reactivity to food stimuli in overweight individuals and individuals with obesity. This support for attentional bias was observed primarily in studies that employed psychophysiological techniques (i.e. electroencephalogram, eye-tracking and functional magnetic resonance imaging). Despite the heterogeneous methodology within the featured studies, all measures of attentional bias demonstrated altered cue-reactivity in individuals with obesity. Considering the theorized implications of attentional biases on obesity pathology, researchers are encouraged to replicate flagship studies to strengthen these inferences.


Assuntos
Sinais (Psicologia) , Comportamento Alimentar/psicologia , Obesidade/psicologia , Sobrepeso/psicologia , Percepção Visual , Adulto , Atenção , Viés , Humanos , Motivação , Obesidade/fisiopatologia , Sobrepeso/fisiopatologia , Estimulação Luminosa
9.
FEMS Microbiol Lett ; 145(3): 451-5, 1996 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-8978100

RESUMO

The multiallelic mating type locus B alpha 1 of Schizophyllum commune encodes a pheromone receptor and putative pheromone genes. A comparison of two alleles encoding receptors that share the same specificity B alpha 1 was performed using strains of different geographic origin. The amino acid sequence alignment revealed strong conservation of the largest part of the receptor. Only in the distal C-terminus major amino acid was divergence encountered. This C-terminal region of 117 of the total of 639 amino acids was shown to be unnecessary for function in vivo by transformation experiments.


Assuntos
Células Quimiorreceptoras/fisiologia , Schizophyllum/genética , Alelos , Sequência de Aminoácidos , Proteínas de Bactérias , Evolução Biológica , Southern Blotting , DNA Complementar , Escherichia coli/genética , Genes Fúngicos/genética , Genes Fúngicos Tipo Acasalamento , Variação Genética , Dados de Sequência Molecular , Mapeamento por Restrição , Schizophyllum/química , Especificidade da Espécie , Transformação Genética
10.
FEMS Microbiol Lett ; 119(1-2): 243-7, 1994 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-8039665

RESUMO

The basis of the auxotrophic ura1 phenotype in Schizophyllum commune has been investigated. Two point mutations causing changes in conserved amino acid positions 62 (from lysine to glutamate) and 79 (from leucine to phenylalanine) most likely are the cause for the observed phenotype, whereas the overall gene structure was unchanged. Since reversion rates in this locus are extremely low, a single point mutation could not be expected to be the cause for the mutation. Besides the two point mutations expected to be induced by UV mutagenesis, the two alleles investigated from independently isolated strains differ by approximately 7% in nucleic acid sequence and about 3% in amino acid sequence, indicating a distant relationship between the strains used.


Assuntos
Alelos , Orotidina-5'-Fosfato Descarboxilase/genética , Schizophyllum/genética , Sequência de Aminoácidos , Sequência de Bases , Dados de Sequência Molecular , Mutação , Fenótipo , Reação em Cadeia da Polimerase , Transformação Genética
11.
J Med Microbiol ; 42(6): 404-10, 1995 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7791204

RESUMO

The pheno- and genotypes of Shiga-like toxins (SLTs) in non-O157 Escherichia coli strains from patients with haemolytic uraemic syndrome were determined. The clinical isolates investigated were from Italy and Germany and belonged to serotypes O22:H8, O26:H-, O26:H11, O91:H-, O111:H- and O128:H-; one isolate was non-typable. SLT genotypes were analysed by complete nucleotide sequence analysis of the B-subunit genes. The results showed that 14 strains possessed slt-I alone, two contained slt-II alone and five isolates harboured both slt-I and slt-II genes. In only two strains were slt-II-related genes found, together with either slt-I or slt-II. These findings indicate that variants of SLT-II are rarely found in non-O157 E. coli isolates from patients with haemolytic uraemic syndrome. Polymerase chain reaction (PCR) with Taq cycle sequencing was found to be a suitable method for classification of slt genotypes.


Assuntos
Toxinas Bacterianas/genética , Infecções por Escherichia coli/microbiologia , Escherichia coli/genética , Síndrome Hemolítico-Urêmica/microbiologia , Sequência de Bases , Southern Blotting , Citotoxinas/genética , Primers do DNA/química , Enterotoxinas/genética , Escherichia coli/classificação , Genes Bacterianos , Genótipo , Alemanha , Humanos , Itália , Dados de Sequência Molecular , Testes de Neutralização , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Análise de Sequência , Sorotipagem , Toxina Shiga I , Toxina Shiga II
12.
Microbiol Res ; 153(4): 377-88, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10052159

RESUMO

The internal transcribed spacer sequences spanning the regions between the 17S and 25S rRNAs (ITS1 and ITS2) and including the complete sequence of the 5.8S rRNA were used for phylogenetic analyses. This approach to define phylogenetic relationships within the genus Tricholoma was tested using different isolates of T. terreum. Fruitbodies identified in nature were analysed in order to allow use of morphology for taxonomy. The isolates from different locations were closely related as could be expected for one species. Thus, the method could be applied to different Tricholoma species. Three clusters within the genus Tricholoma can be distinguished with four additional species not included in any of these clusters. Molecular analyses of two Cortinarius species confirm a phylogenetically distinct genus.


Assuntos
Agaricales/classificação , Agaricales/genética , Filogenia , Agaricales/crescimento & desenvolvimento , Sequência de Bases , DNA Fúngico/genética , DNA Ribossômico/genética , Dados de Sequência Molecular , Reação em Cadeia da Polimerase/métodos , RNA Fúngico/genética , RNA Ribossômico/genética , Alinhamento de Sequência , Análise de Sequência de DNA , Especificidade da Espécie
14.
Appl Microbiol Biotechnol ; 56(5-6): 602-12, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11601606

RESUMO

Mushroom production is dependent on the quality of the spawn used to inoculate the cultures. In order to produce high-quality spawn, breeding programs for strains resistant to certain diseases and able to form high-quality fruit bodies under standard growth conditions are necessary. The investigation of the molecular basis for mating provides access to the use of mating-type genes in order to facilitate breeding. For research purposes, two mushroom-forming homobasidiomycetes have been used due to their easy cultivation and sexual propagation on defined minimal media: Schizophyllum commune and Coprinus cinereus. The mating-type genes control formation of the dikaryon from two haploid strains. Only the dikaryon is fertile and able to form mushrooms under the right environmental conditions. These genes are now used in mating-type-assisted breeding programs for economically important mushrooms, especially the white button mushroom, Agaricus bisporus, and the oyster mushroom, Pleurotus ostreatus, aiming at high-yield and high-quality standard mushroom production. Most mushroom species posses two mating-type loci that control their breeding. The genes encoded in the A loci lead to the formation of transcription factors that belong to the class of homeodomain proteins. Active transcription factors are formed by heterodimerization of two proteins of different allelic specificities. In nature, this is only the case if two cells of different mating type have fused to combine the different proteins in one cytoplasm. While fusion in homobasidiomycetes is found irrespectively of mating type, exchange of nuclei between mating mycelia is dependent on the products of the B mating-type loci. The B genes form a pheromone and receptor system that enables the fungi to initiate nuclear migration. The molecular details of the two genetic systems controlling breeding in basidiomycetes are presented in this review.


Assuntos
Basidiomycota/genética , Basidiomycota/fisiologia , Proteínas Fúngicas/genética , Genes Fúngicos , Genes Fúngicos Tipo Acasalamento , Cruzamentos Genéticos , Proteínas Fúngicas/metabolismo , Engenharia Genética/métodos , Reprodução
15.
Fungal Genet Biol ; 27(2-3): 146-52, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10441440

RESUMO

In the homobasidiomycete Schizophyllum commune the mating type genes of the B locus encode pheromones and pheromone receptors in multiple allelic specificities. Interaction of non-self pheromones and receptors leads to induction of B-regulated development easily scored in S. commune by the "flat" phenotype which lacks aerial mycelium formation and shows aberrant hyphal morphology. In contrast, self pheromones are not recognized and B-regulated development is not induced. Natural and mutant alleles of receptors have been analyzed for their specificity in transformation assays, and parts of the receptor involved in ligand discrimination can be described. The biological role of pheromone response in S. commune is assumed to be connected to nuclear migration based on the observation that wild-type cells with a receptor gene of different specificity lead to cells capable of nuclear uptake. Other possible roles for pheromone function are discussed.


Assuntos
Proteínas Fúngicas/genética , Regulação Fúngica da Expressão Gênica , Feromônios/genética , Schizophyllum/genética , Schizophyllum/fisiologia , Alelos , Sequência de Aminoácidos , Proteínas Fúngicas/metabolismo , Genes Fúngicos , Genes Fúngicos Tipo Acasalamento , Dados de Sequência Molecular , Feromônios/metabolismo
16.
Curr Genet ; 35(5): 551-6, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10369963

RESUMO

To identify genes regulated by the B mating-type genes a differential RNA display was established for the homobasidiomycete Schizophyllum commune and a gene, brt1, was identified. The mRNA concerned is highly abundant in monokaryotic mycelia and is down-regulated in matings in which either the B genes alone or else both the A and B genes are different between the mates. This places the gene brt1 under the control of the pheromone response system of S. commune encoded by the B mating-type loci. Sequence analysis revealed similarity to a novel protein family, two members of which have been shown to inhibit translational re-initiation.


Assuntos
Proteínas Fúngicas/genética , Regulação Fúngica da Expressão Gênica , Schizophyllum/genética , Sequência de Bases , Northern Blotting , Mapeamento Cromossômico , Clonagem Molecular , Cruzamentos Genéticos , Desoxirribonuclease BamHI/genética , Regulação para Baixo , Proteínas Fúngicas/metabolismo , Deleção de Genes , Marcadores Genéticos , Técnicas Genéticas , Hibridização In Situ/métodos , Dados de Sequência Molecular , RNA Fúngico , Reprodução/genética , Schizophyllum/crescimento & desenvolvimento , Homologia de Sequência de Aminoácidos , Transcrição Gênica
17.
Curr Genet ; 36(3): 159-64, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10501939

RESUMO

A gene that exhibits sexually induced transcript accumulation, mtd1, was identified physically linked to a locus that is also under control of the mating-type genes. Genomic and cDNA sequence analyses were performed to determine a large open reading frame which starts with the amino-acid sequence M-A-T-E-D. The ORF showed similarities to a novel family of peptide transporters with at least 12 putative transmembrane structures. A gene disruption resulted in a growth-phenotype with slow aerial mycelium formation that could be complemented with peptone or uracil added to the growth medium.


Assuntos
Proteínas de Transporte/química , Proteínas de Transporte/genética , Proteínas de Transporte/fisiologia , Genes Fúngicos/genética , Genes Fúngicos Tipo Acasalamento , Proteínas de Membrana Transportadoras , Proteínas de Protozoários , Schizophyllum/citologia , Schizophyllum/genética , Sequência de Aminoácidos , Sequência de Bases , Northern Blotting , Clonagem Molecular , Deleção de Genes , Teste de Complementação Genética , Dados de Sequência Molecular , Fases de Leitura Aberta/genética , Fenótipo , RNA/análise , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos
18.
Fungal Genet Biol ; 30(3): 191-6, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11035940

RESUMO

The pheromone receptor system of the basidiomycete Schizophyllum commune is capable of ligand discrimination to confer mating specificity. The pheromone receptors of the B alpha locus were investigated for ligand discrimination in a strategy of domain swapping experiments. Several altered phenotypes of chimeric receptors have been found. These include constitutive pheromone receptors which need no ligand for activation of the downstream cascade of events. In addition, receptors still dependent on ligand were identified that had altered pheromone activation profiles, including promiscuous receptors that are activated by pheromones of all nine specificities, including the former self. In addition, highly discriminative receptors were created which are activated by only two of the eight non-self-specificities. The chimeric receptors identify the last third of the receptor as the determinant for B alpha 1 specificity, whereas B alpha 2 specificity resides in noncontiguous domains covering the first and middle parts of the receptor molecule.


Assuntos
Receptores de Peptídeos/química , Receptores de Peptídeos/metabolismo , Schizophyllum/fisiologia , Fatores de Transcrição , Sequência de Aminoácidos , Clonagem Molecular , Ligantes , Dados de Sequência Molecular , Fenótipo , Feromônios/metabolismo , Receptores de Fator de Acasalamento , Receptores de Peptídeos/genética , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Schizophyllum/genética , Transformação Genética
19.
Fungal Genet Biol ; 26(3): 190-7, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10361033

RESUMO

The homobasidiomycete Schizophyllum commune encodes a multiallelic pheromone receptor system that distinguishes more than 20 nonself from at least 2 self pheromones. The well-investigated pheromone response system of the yeast Saccharomyces cerevisiae was used to link the FUS1::lacZ reporter system to the heterologous pheromone receptors from S. commune. To investigate yeast G-protein binding, the unchanged heterologous receptor was compared to constructs carrying an exchange of the 3rd cytoplasmatic loop for the Ste2 sequence. A better coupling could be achieved with the altered constructs. In order to examine activation by single pheromones, an artificial peptide based on the sequence of a new putative pheromone gene, bap2(1), in the Balpha2 mating-type locus encoding the shortest pheromone found so far in fungal mating types was used. Thus, we have reassembled the pheromone recognition of the basidiomycete S. commune and constructed a system ideal for specificity analysis in the yeast S. cerevisiae.


Assuntos
Células Quimiorreceptoras/metabolismo , Genes Fúngicos , Genes Fúngicos Tipo Acasalamento , Schizophyllum/metabolismo , Sequência de Aminoácidos , Sequência de Bases , Genes Reporter/genética , Ligantes , Dados de Sequência Molecular , Schizophyllum/química , Schizophyllum/genética , Homologia de Sequência do Ácido Nucleico , Transfecção
20.
J Basic Microbiol ; 40(1): 65-70, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10746200

RESUMO

Using arbitrary primers for a PCR reaction on cDNA from different mating interactions, genes differentially expressed in a mating-type dependent manner have been identified. The cDNAs were prepared from mRNA extracted from liquid grown cultures of the fungus in order to prevent further steps in development and increase the possibility of identifying genes directly under control of the mating type system. A reaction using a monokaryotic strain was compared to a semicompatible mating reaction induced for B-regulated development and a reaction using a fully compatible mating. In the comparison of silver-stained, non-denaturing polyacrylamide gel separation of the PCR products bands differentially detected between the samples were cloned and subjected to further analysis. Bands were characterized which were present in both mating reactions but absent in the monokaryon while the third band was specifically absent in the fully compatible mating interaction. Sequence analysis allowed design of specific primers for verification of differential expression in a semi-quantitative PCR. Thus, use of radioactivity was not necessary for the fast and reproducible method identifying genes specifically regulated by mating reactions.


Assuntos
Genes Fúngicos , Genes Fúngicos Tipo Acasalamento , Reação em Cadeia da Polimerase/métodos , Schizophyllum/genética , Clonagem Molecular , Perfilação da Expressão Gênica , Reprodução/genética
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