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1.
J Dairy Sci ; 106(1): 407-420, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36400619

RESUMO

Sperm motility is directly related to the ability of sperm to move through the female reproductive tract to reach the ovum. Sperm motility is a complex trait that is influenced by environmental and genetic factors and is associated with male fertility, oocyte penetration rate, and reproductive success of cattle. In this study we carried out a GWAS in Italian Holstein bulls to identify candidate regions and genes associated with variations in progressive and total motility (PM and TM, respectively). After quality control, the final data set consisted of 5,960 records from 949 bulls having semen collected in 10 artificial insemination stations and genotyped at 412,737 SNPs (call rate >95%; minor allele frequency >5%). (Co)variance components were estimated using single trait mixed models, and associations between SNPs and phenotypes were assessed using a genomic BLUP approach. Ten windows that explained the greatest percentage of genetic variance were located on Bos taurus autosomes 1, 2, 4, 6, 7, 23, and 26 for TM and Bos taurus autosomes 1, 2, 4, 6, 8, 16, 23, and 26 for PM. A total of 150 genes for TM and 72 genes for PM were identified within these genomic regions. Gene Ontology enrichment analyses identified significant Gene Ontology terms involved with energy homeostasis, membrane functions, sperm-egg interactions, protection against oxidative stress, olfactory receptors, and immune system. There was significant enrichment of quantitative trait loci for fertility, calving ease, immune response, feed intake, and carcass weight within the candidate windows. These results contribute to understanding the architecture of the genetic control of sperm motility and may aid in the development of strategies to identify subfertile bulls and improve reproductive success.


Assuntos
Sêmen , Motilidade dos Espermatozoides , Animais , Bovinos/genética , Feminino , Masculino , Genômica , Locos de Características Quantitativas , Sêmen/fisiologia , Motilidade dos Espermatozoides/genética , Espermatozoides
2.
Anim Genet ; 51(2): 177-191, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31967365

RESUMO

The domestic Asian water buffalo (Bubalus bubalis) is found on all five continents, with a global population of some 202 million. The livelihoods of more people depend on this species than on any other domestic animal. The two distinct types (river and swamp) descended from different wild Asian water buffalo (Bubalus arnee) populations that diverged some 900 kyr BP and then evolved in separate geographical regions. After domestication in the western region of the Indian subcontinent (ca. 6300 years BP), the river buffalo spread west as far as Egypt, the Balkans and Italy. Conversely, after domestication in the China/Indochina border region ca. 3000-7000 years BP, swamp buffaloes dispersed through south-east Asia and China as far as the Yangtze River valley. Molecular and morphological evidence indicates that swamp buffalo populations have strong geographic genetic differentiation and a lack of gene flow, but strong phenotypic uniformity. In contrast, river buffalo populations show a weaker phylogeographic structure, but higher phenotypic diversity (i.e. many breeds). The recent availability of a high-quality reference genome and of a medium-density marker panel for genotyping has triggered a number of genome-wide investigations on diversity, evolutionary history, production traits and functional elements. The growing molecular knowledge combined with breeding programmes should pave the way to improvements in production, environmental adaptation and disease resistance in water buffalo populations worldwide.


Assuntos
Búfalos/genética , Domesticação , Variação Genética , Animais , Filogeografia
3.
Mol Ecol Resour ; 17(5): 1072-1089, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27801969

RESUMO

With the increasing availability of both molecular and topo-climatic data, the main challenges facing landscape genomics - that is the combination of landscape ecology with population genomics - include processing large numbers of models and distinguishing between selection and demographic processes (e.g. population structure). Several methods address the latter, either by estimating a null model of population history or by simultaneously inferring environmental and demographic effects. Here we present samßada, an approach designed to study signatures of local adaptation, with special emphasis on high performance computing of large-scale genetic and environmental data sets. samßada identifies candidate loci using genotype-environment associations while also incorporating multivariate analyses to assess the effect of many environmental predictor variables. This enables the inclusion of explanatory variables representing population structure into the models to lower the occurrences of spurious genotype-environment associations. In addition, samßada calculates local indicators of spatial association for candidate loci to provide information on whether similar genotypes tend to cluster in space, which constitutes a useful indication of the possible kinship between individuals. To test the usefulness of this approach, we carried out a simulation study and analysed a data set from Ugandan cattle to detect signatures of local adaptation with samßada, bayenv, lfmm and an FST outlier method (FDIST approach in arlequin) and compare their results. samßada - an open source software for Windows, Linux and Mac OS X available at http://lasig.epfl.ch/sambada - outperforms other approaches and better suits whole-genome sequence data processing.


Assuntos
Biota , Biologia Computacional/métodos , Ecossistema , Exposição Ambiental , Genômica/métodos , Adaptação Biológica , Animais , Bovinos , Genética Populacional , Genótipo , Seleção Genética
4.
Anim Genet ; 47(4): 463-70, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26953226

RESUMO

Iranian livestock diversity is still largely unexplored, in spite of the interest in the populations historically reared in this country located near the Fertile Crescent, a major livestock domestication centre. In this investigation, the genetic diversity and differentiation of 10 Iranian indigenous fat-tailed sheep breeds were investigated using 18 microsatellite markers. Iranian breeds were found to host a high level of diversity. This conclusion is substantiated by the large number of alleles observed across loci (average 13.83, range 7-22) and by the high within-breed expected heterozygosity (average 0.75, range 0.72-0.76). Iranian sheep have a low level of genetic differentiation, as indicated by the analysis of molecular variance, which allocated a very small proportion (1.67%) of total variation to the between-population component, and by the small fixation index (FST  = 0.02). Both Bayesian clustering and principal coordinates analysis revealed the absence of a detectable genetic structure. Also, no isolation by distance was observed through comparison of genetic and geographical distances. In spite of high within-breed variation, signatures of inbreeding were detected by the FIS indices, which were positive in all and statistically significant in three breeds. Possible factors explaining the patterns observed, such as considerable gene flow and inbreeding probably due to anthropogenic activities in the light of population management and conservation programmes, are discussed.


Assuntos
Variação Genética , Genética Populacional , Carneiro Doméstico/genética , Alelos , Animais , Teorema de Bayes , Genótipo , Heterozigoto , Endogamia , Irã (Geográfico) , Repetições de Microssatélites
5.
J Dairy Sci ; 99(5): 3646-3653, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26971153

RESUMO

Accurate pedigrees are essential to optimize genetic improvement and conservation of animal genetic resources. In goats, the use of mating groups and kidding management procedures hamper the identification of parentage. Small panels of single nucleotide polymorphisms (SNP) have been proposed in other species to substitute microsatellites for parentage assessment. Using data from the current GoatSNP50 chip, we developed a new 3-step procedure to identify a low-density SNP panel for highly accurate parentage assessment. Methodologies for SNP selection used in other species are less suitable in the goat because of uncertainties in the genome assembly. The procedure developed in this study is based on parent-offspring identification and on estimation of Mendelian errors, followed by canonical discriminant analysis identification and stepwise regression reduction. Starting from a reference sample of 109 Alpine goats with known pedigree relationships, we first identified a panel of 200 SNP that was further reduced to 2 final panels of 130 and 114 SNP with random coincidental match inclusion of 1.51×10(-57) and 2.94×10(-34), respectively. In our reference data set, all panels correctly identified all parent-offspring combinations, revealing a 40% pedigree error rate in the information provided by breeders. All reference trios were confirmed by official tests based on microsatellites. Panels were also tested on Saanen and Teramana breeds. Although the testing on a larger set of breeds in the reference population is still needed to validate these results, our findings suggest that our procedure could identify SNP panels for accurate parentage assessment in goats or in other species with unreliable marker positioning.


Assuntos
Cabras/genética , Polimorfismo de Nucleotídeo Único , Animais , Cruzamento , Repetições de Microssatélites , Linhagem
6.
Anim Genet ; 47(1): 19-27, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26559490

RESUMO

Local breeds of livestock are of conservation significance as components of global biodiversity and as reservoirs of genetic variation relevant to the future sustainability of agriculture. One such rare historic breed, the Chillingham cattle of northern England, has a 350-year history of isolation and inbreeding yet shows no diminution of viability or fertility. The Chillingham cattle have not been subjected to selective breeding. It has been suggested previously that the herd has minimal genetic variation. In this study, high-density SNP genotyping with the 777K SNP chip showed that 9.1% of loci on the chip are polymorphic in the herd, compared with 62-90% seen in commercial cattle breeds. Instead of being homogeneously distributed along the genome, these loci are clustered at specific chromosomal locations. A high proportion of the Chillingham individuals examined were heterozygous at many of these polymorphic loci, suggesting that some loci are under balancing selection. Some of these frequently heterozygous loci have been implicated as sites of recessive lethal mutations in cattle. Linkage disequilibrium equal or close to 100% was found to span up to 1350 kb, and LD was above r(2) = 0.25 up to more than 5000 kb. This strong LD is consistent with the lack of polymorphic loci in the herd. The heterozygous regions in the Chillingham cattle may be the locations of genes relevant to fitness or survival, which may help elucidate the biology of local adaptation in traditional breeds and facilitate selection for such traits in commercial cattle.


Assuntos
Bovinos/genética , Heterozigoto , Endogamia , Polimorfismo de Nucleotídeo Único , Animais , Conservação dos Recursos Naturais , Inglaterra , Feminino , Loci Gênicos , Genótipo , Técnicas de Genotipagem , Masculino
7.
Eur J Endocrinol ; 172(5): 603-8, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25693592

RESUMO

OBJECTIVES: Pituitary stem cells play a role in the oncogenesis of human adamantinomatous craniopharyngiomas (aCPs). We hypothesized that crosstalk between the Wnt/ß-catenin and Sonic Hedgehog (SHH) pathways, both of which are important in normal pituitary development, would contribute to the pathogenesis of aCPs. DESIGN: To explore the mRNA and protein expression of components of the SHH signaling pathway in aCPs and their relationship with the identification of CTNNB1/ß-catenin mutations and patients outcomes. PATIENTS AND METHODS: In 18 aCP samples, CTNNB1 was sequenced, and the mRNA expression levels of SHH pathway members (SHH, PTCH1, SMO, GLI1, GLI2, GLI3, and SUFU) and SMO, GLI1, GLI3, SUFU, ß-catenin, and Ki67 proteins were evaluated by quantitative real-time PCR and immunohistochemistry respectively. Anterior normal pituitaries were used as controls. Associations between molecular findings and clinical data were analyzed. RESULTS: The aCPs presented higher mRNA expression of SHH (+400-fold change (FC); P<0.01), GLI1 (+102-FC; P<0.001), and GLI3 (+5.1-FC; P<0.01) than normal anterior pituitaries. Longer disease-free survival was associated with low SMO and SUFU mRNA expression (P<0.01 and P=0.02 respectively). CTNNB1/ß-catenin mutations were found in 47% of the samples. aCPs with identified mutations presented with higher mRNA expression of SMO and GLI1 (+4.3-FC; P=0.02 and +10.2-FC; P=0.03 respectively). SMO, GLI1, GLI3, and SUFU staining was found in 85, 67, 93, and 64% of the samples respectively. Strong GLI1 and GLI3 staining was detected in palisade cells, which also labeled Ki67, a marker of cell proliferation. CONCLUSIONS: The upregulation of SHH signaling occurs in aCPs. Thus, activation of Wnt/ß-catenin and SHH pathways, both of which are important in pituitary embryogenesis, appears to contribute to the pathogenesis of aCP.


Assuntos
Craniofaringioma/metabolismo , Proteínas Hedgehog/metabolismo , Neoplasias Hipofisárias/metabolismo , Adolescente , Adulto , Criança , Craniofaringioma/genética , Feminino , Proteínas Hedgehog/genética , Humanos , Masculino , Mutação , Neoplasias Hipofisárias/genética , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Receptor Cross-Talk , Transdução de Sinais/genética , Regulação para Cima , Adulto Jovem , beta Catenina/metabolismo
9.
Anim Genet ; 44(1): 69-78, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22506921

RESUMO

Since its domestication, about 5000 years ago, the donkey (Equus asinus) has been extensively used as a work or draft animal in agricultural activities and for the transportation of people and goods. In the last century, technology improvement and growing mechanization strongly affected agriculture and the management and use of this livestock species in the industrialized countries. Nowadays, the use of donkeys for work or transport has almost disappeared, together with the need for mules or hinny breeding. During the last five decades, Italian autochthonous donkey populations suffered from a severe reduction in population size, which led to the extinction of several breeds. At present, eight breeds remain, all classified by FAO as critically endangered or endangered: Asinara, Pantesco, Grigio Siciliano, Romagnolo, Amiatino, Sardo Grigio, Martina Franca, and Ragusano. To evaluate the extant genetic variability of Italian donkeys, we typed 16 microsatellite loci in 258 individuals from these breeds. The results highlighted moderate levels of inbreeding ( F (IS) = 0.127) and a significant partition of genetic variation into breeds, as suggested by fixation index ( F (ST) = 0.109) and analysis of molecular variance (10.86% of total variation assigned to the between-breeds level) analyses. This was confirmed by a Bayesian clustering procedure that also highlighted a further partitioning at lower hierarchical levels corresponding to the farms of origin. This evidence suggests that an effective management strategy for Italian donkey populations should focus on breeds as conservation units. However, this requires a synergic management strategy at the farm level to maintain diversity and avoid inbreeding.


Assuntos
Equidae/genética , Variação Genética , Repetições de Microssatélites , Alelos , Criação de Animais Domésticos , Animais , Teorema de Bayes , Núcleo Celular/genética , Conservação dos Recursos Naturais , Demografia , Itália , Modelos Genéticos , Densidade Demográfica
10.
G Ital Dermatol Venereol ; 147(4): 341-8, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23007209

RESUMO

AIM: Sexually transmitted infections (STIs) are increasing worldwide, mostly due to changing sexual behavior s (larger numbers of sexual partners, concurrent relationships, increasing proportion of adolescents engaging in sexual intercourse at young age, and inconsistent condom use with new partners). In Italy, few data are available about STI spread, since most infections are not subjected to mandatory notification. METHODS: In this article, the occurrence of STIs in a random sample attending a STI Unit in Florence, Italy, is reported. Results were obtained through the administration of an anonymous questionnaire that patients could complete spontaneously in the waiting room while waiting for the visit. Self-reported questions allowed to collect information about socio-demographic and clinical data, sexual behavior and perception of risk. RESULTS: Overall, 469 patients (321 males, 148 females) participated in the study. Age ranged from 16 to 70 years. Male patients who referred to engage sexual intercourse with men (MSM) were 133; females who had sex with women (FSF) were 5, while 24 patients declared to have sex with both males and females (bisexual); 59.7% (N.=280) of participants reported they had a stable relationship, but 20% of these reported they had had sex with more than five partners during the last 12 months. The use of condoms is declared to be very infrequent, especially in the two extreme age ranges. Fifty percent of patients had been diagnosed an STI in their life, particularly syphilis (39.3%), genital warts (64.6%) and chlamydial infections (42.9%). Among those subjects who had contracted an STI (including non-curable viral infections, i.e., HIV and herpes genitalis) 32.4% referred they never used condoms. CONCLUSION: The authors discuss their results compared to the existing literature, and focus on identification of risk factors associated with self-reported STIs. Although conducted on a small population, this study provides a basis for targeting prevention and control strategies on our high-risk patients.


Assuntos
Infecções Sexualmente Transmissíveis/epidemiologia , Adolescente , Adulto , Idoso , Feminino , Humanos , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Comportamento Sexual , Fatores Socioeconômicos , Adulto Jovem
11.
Anim Genet ; 41 Suppl 1: 47-63, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20500755

RESUMO

In livestock genetic resource conservation, decision making about conservation priorities is based on the simultaneous analysis of several different criteria that may contribute to long-term sustainable breeding conditions, such as genetic and demographic characteristics, environmental conditions, and role of the breed in the local or regional economy. Here we address methods to integrate different data sets and highlight problems related to interdisciplinary comparisons. Data integration is based on the use of geographic coordinates and Geographic Information Systems (GIS). In addition to technical problems related to projection systems, GIS have to face the challenging issue of the non homogeneous scale of their data sets. We give examples of the successful use of GIS for data integration and examine the risk of obtaining biased results when integrating datasets that have been captured at different scales.


Assuntos
Animais Domésticos/genética , Biodiversidade , Sistemas de Informação Geográfica , Doenças dos Animais/epidemiologia , Animais , Animais Domésticos/fisiologia , Conservação dos Recursos Naturais
12.
Anim Genet ; 41 Suppl 1: 64-77, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20500756

RESUMO

The genetic diversity of the world's livestock populations is decreasing, both within and across breeds. A wide variety of factors has contributed to the loss, replacement or genetic dilution of many local breeds. Genetic variability within the more common commercial breeds has been greatly decreased by selectively intense breeding programmes. Conservation of livestock genetic variability is thus important, especially when considering possible future changes in production environments. The world has more than 7500 livestock breeds and conservation of all of them is not feasible. Therefore, prioritization is needed. The objective of this article is to review the state of the art in approaches for prioritization of breeds for conservation, particularly those approaches that consider molecular genetic information, and to identify any shortcomings that may restrict their application. The Weitzman method was among the first and most well-known approaches for utilization of molecular genetic information in conservation prioritization. This approach balances diversity and extinction probability to yield an objective measure of conservation potential. However, this approach was designed for decision making across species and measures diversity as distinctiveness. For livestock, prioritization will most commonly be performed among breeds within species, so alternatives that measure diversity as co-ancestry (i.e. also within-breed variability) have been proposed. Although these methods are technically sound, their application has generally been limited to research studies; most existing conservation programmes have effectively primarily based decisions on extinction risk. The development of user-friendly software incorporating these approaches may increase their rate of utilization.


Assuntos
Animais Domésticos/genética , Conservação dos Recursos Naturais/métodos , Animais , Cruzamento , Variação Genética , Seleção Genética
13.
Anim Genet ; 40(1): 18-26, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19016674

RESUMO

The effectiveness of single nucleotide polymorphisms (SNPs) for the assignment of cattle to their source breeds was investigated by analysing a panel of 90 SNPs assayed on 24 European breeds. Breed assignment was performed by comparing the Bayesian and frequentist methods implemented in the STRUCTURE 2.2 and GENECLASS 2 software programs. The use of SNPs for the reallocation of known individuals to their breeds of origin and the assignment of unknown individuals was tested. In the reallocation tests, the methods implemented in STRUCTURE 2.2 performed better than those in GENECLASS 2, with 96% vs. 85% correct assignments respectively. In contrast, the methods implemented in GENECLASS 2 showed a greater correct assignment rate in allocating animals treated as unknowns to a reference dataset (62% vs. 51% and 80% vs. 65% in field tests 1 and 2 respectively). These results demonstrate that SNPs are suitable for the assignment of individuals to reference breeds. The results also indicate that STRUCTURE 2.2 and GENECLASS 2 can be complementary tools to assess breed integrity and assignment. Our findings also stress the importance of a high-quality reference dataset in allocation studies.


Assuntos
Bovinos/genética , Polimorfismo de Nucleotídeo Único , Algoritmos , Animais , Teorema de Bayes , Especificidade da Espécie
14.
Horm Metab Res ; 39(6): 425-9, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17578759

RESUMO

Only few studies have addressed the interindividual variation and tissue specificity of glucocorticoid (GC) sensitivity in healthy individuals, a phenomenon observed in pathological conditions. Alternative splicing of the glucocorticoid receptor (GR) produces alpha and beta isoforms. GRbeta has dominant-negative effects on hormone-induced GRalpha effects, and an increased expression of the GRbeta has been associated with glucocorticoid resistance. We determined, using a simple, rapid, and accurate Real-Time PCR assay, the individual mRNAs expression of GRalpha and GRbeta in 26 normal subjects (mean+/-SE, age 30+/-6 years; 12 males and 14 females), in order to evaluate the role of these isoforms in glucocorticoid sensitivity in health. Glyceraldehydes-3-phosphate dehydrogenase (GAPDH) was used as a housekeeper gene. GRalpha/GAPDH, GRbeta/GAPDH and GRalpha/GRbeta ratios showed a normal distribution. We observed a higher expression of GRalpha compared to GRbeta and an interindividual variability in the GRalpha, GRbeta, and GAPDH gene expressions in the young healthy population. In addition, no correlation was observed between GRalpha/GRbeta ratio and the dexamethasone (DEX) doses needed to suppress plasma cortisol, GRalpha/GRbeta ratio and the concentration of DEX that caused inhibition of Con-A stimulated cell proliferation, and GRalpha/GRbeta ratio and the affinity of GR (Kd) of each subject. Therefore, the variability of GC sensitivity observed in normal subjects can not be ascribed to the variation in the GRalpha and GRbeta expression.


Assuntos
Glucocorticoides/farmacologia , Receptores de Glucocorticoides/genética , Adulto , Feminino , Humanos , Masculino , RNA Mensageiro/análise , Receptores de Glucocorticoides/fisiologia
15.
Anim Genet ; 38(2): 147-53, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17326802

RESUMO

The verification of the breed origin of animal products is relevant for food safety and authenticity. We assessed the suitability of AFLP molecular markers in the assignment of cattle individuals to their breed of origin. Three hundred and ninety-six animals belonging to 16 cattle breeds genotyped with 141 AFLP markers were used as reference data set. Assignment was performed with likelihood (aflpop) and Bayesian (structure) methods. The Bayesian approach was superior to the likelihood algorithm with respect to (i) the correct assignment of simulated individuals to their breed of origin (93% vs. 81% respectively), (ii) the correct assignment of 44 sampled Romagnola animals (91% vs. 45% respectively) and (iii) the correct classification of animals belonging to a breed that was not included within the reference dataset. Thus, AFLP profiling in combination with the Bayesian approach seems a useful tool for breed assignment.


Assuntos
Cruzamento/métodos , Bovinos/classificação , Bovinos/genética , Marcadores Genéticos/genética , Animais , Teorema de Bayes , Estudos de Avaliação como Assunto , Genótipo , Funções Verossimilhança , Modelos Genéticos , Técnicas de Amplificação de Ácido Nucleico , Polimorfismo de Fragmento de Restrição
16.
Neurochem Int ; 38(1): 75-82, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10913690

RESUMO

Choline-O-acetyltransferase (ChAT) is the enzyme which catalyses the biosynthesis of the neurotransmitter acetylcholine in cholinergic neurons. Here we show that in mouse cholinergic NS-20Y neuroblastoma cells cultured in the presence of either okadaic acid (serine/threonine phosphatases 1 and 2A inhibitor) or KN-62 (CaM kinase inhibitor) ChAT activity and mRNA either increased or decreased as a function of the drug concentration, respectively. After 24 h exposure, okadaic acid exerted a dramatic effect on cell morphology; cells became round and had no more neurites. On the contrary, KN-62 induced a slight morphological differentiation of the cells. The present results suggest that phosphatases 1 and 2A and CaM kinase could mediate regulation of ChAT gene expression.


Assuntos
1-(5-Isoquinolinasulfonil)-2-Metilpiperazina/análogos & derivados , Proteínas Quinases Dependentes de Cálcio-Calmodulina/fisiologia , Colina O-Acetiltransferase/biossíntese , Inibidores Enzimáticos/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Proteínas de Neoplasias/biossíntese , Neuroblastoma/patologia , Ácido Okadáico/farmacologia , Fosfoproteínas Fosfatases/fisiologia , 1-(5-Isoquinolinasulfonil)-2-Metilpiperazina/farmacologia , Animais , Proteínas Quinases Dependentes de Cálcio-Calmodulina/antagonistas & inibidores , Colina O-Acetiltransferase/genética , Indução Enzimática/efeitos dos fármacos , Camundongos , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/genética , Neuroblastoma/enzimologia , Fosfoproteínas Fosfatases/antagonistas & inibidores , Fosforilação/efeitos dos fármacos , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , RNA Neoplásico/biossíntese , RNA Neoplásico/genética , Células Tumorais Cultivadas/efeitos dos fármacos , Células Tumorais Cultivadas/enzimologia
17.
Eur J Neurosci ; 10(5): 1644-53, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9751137

RESUMO

Choline acetyltransferase (ChAT), the enzyme which catalyses the biosynthesis of the neurotransmitter acetylcholine, exists in a soluble and membrane-bound form in cholinergic nerve terminals of different animal species. This study was performed on the enzyme present in Drosophila central nervous system. We show that the two forms of the enzyme have the same apparent molecular weight (75 kDa) when analysed by immunoblotting using an antibody we raised against the recombinant enzyme. According to different authors, membrane-bound enzyme might be associated with synaptic vesicles or plasma membrane. Subfractionation of Drosophila head homogenates in linear glycerol gradients showed that ChAT does not associate with synaptic vesicles. Analysis of ChAT activity and immunoreactivity showed that two peaks of ChAT were produced. One peak was present in fractions containing soluble components and the other was associated with rapidly sedimenting membranes containing plasma membranes. ChAT in the first peak was mainly hydrophilic. A large proportion of ChAT associated with rapidly sedimenting membranes was amphiphilic. Further fractionation of these membranes by flotation in sucrose gradients showed that membrane-associated ChAT sedimented in fractions containing plasma membrane marker. Membrane-bound ChAT was neither solubilized nor converted to hydrophilic enzyme after membrane treatment with 1 M hydroxylamine, suggesting that the enzyme is not palmitoylated and therefore not anchored to membrane through thioester-linked long chain fatty acid. Partial solubilization of ChAT present on membranes with urea and carbonate suggests that this form of ChAT is a peripheral membrane protein. Carbonate solubilization of membrane-bound ChAT converted the enzyme from hydrophobic to hydrophilic protein.


Assuntos
Sistema Nervoso Central/enzimologia , Colina O-Acetiltransferase/análise , Drosophila melanogaster/enzimologia , Isoenzimas/análise , Frações Subcelulares/enzimologia , Álcalis/farmacologia , Animais , Membrana Celular/enzimologia , Sistema Nervoso Central/ultraestrutura , Centrifugação com Gradiente de Concentração , Immunoblotting , Solubilidade , Extratos de Tecidos/química , Ureia/farmacologia , Água/química
18.
Prof Inferm ; 50(1): 37-40, 1997.
Artigo em Italiano | MEDLINE | ID: mdl-9248465

RESUMO

The Author analyses the psyco-physical conditions prevailing during illness and hospitalization: from the alterations taking place in the anti-stimulus barriers, to the damages in the oneself perception as a whole. Being at the same time a psychologist and a patient, the A focalizes the value she believes the most specific one of the nursing profession: to care for the body means to care for the person, while the awareness of the suffering conditions means to care for the fundamental needs of reassurance, psycho-physical integration and interpersonal communication.


Assuntos
Continuidade da Assistência ao Paciente , Enfermagem Holística/organização & administração , Relações Enfermeiro-Paciente , Assistência Centrada no Paciente/organização & administração , Psicofisiologia , Humanos
19.
J Neurosci Res ; 45(3): 195-201, 1996 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-8841980

RESUMO

Several neuronal and non-neuronal cell lines express a Ca(2+)-dependent mechanism of transmitter release that can be demonstrated after loading the cells with acetylcholine during culture. In contrast, a particular cell line, the neuroblastoma N18TG-2, was found to be deficient for release. We transfected N18TG-2 cells with a plasmid encoding Torpedo mediatophore, a protein able to translocate acetylcholine in response to calcium. The N18TG-2 cells expressed the Torpedo protein which reached their plasma membrane. At the same time, these cells acquired a Ca(2+)-dependent quantal release mechanism similar to the one naturally expressed by other cell lines. Hence, the presence of mediatophore in the plasma membrane seems essential for quantal release.


Assuntos
Acetilcolina/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Animais , Western Blotting , Neoplasias Encefálicas/metabolismo , Linhagem Celular , DNA Complementar/metabolismo , Eletroforese em Gel de Poliacrilamida , Eletrofisiologia , Humanos , Proteínas do Tecido Nervoso/genética , Neuroblastoma/metabolismo , Técnicas de Patch-Clamp , Torpedo , Transfecção , Células Tumorais Cultivadas , Xenopus
20.
Proc Natl Acad Sci U S A ; 93(11): 5203-7, 1996 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-8643553

RESUMO

Mediatophore is a protein of approximately 200 kDa able to translocate acetylcholine in response to calcium. It was purified from the presynaptic plasma membranes of the electric organ nerve terminals. Mediatophore is a homooligomer of a 16-kDa subunit, homologous to the proteolipid of V-ATPase. Cells of the N18TG-2 neuronal line are not able to produce quantal acetylcholine release. We show here that transfection of N18TG-2 cells with a plasmid encoding the mediatophore subunit restored calcium-dependent release. The essential feature of such a release was its quantal nature, similar to what is observed in situ in cholinergic synapses from which mediatophore was purified.


Assuntos
Acetilcolina/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Transfecção , Animais , Linhagem Celular , Células Clonais , Expressão Gênica , Cinética , Substâncias Macromoleculares , Proteínas do Tecido Nervoso/biossíntese , Neuroblastoma , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/metabolismo , Torpedo , Células Tumorais Cultivadas
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