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1.
Genet Sel Evol ; 51(1): 62, 2019 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-31703548

RESUMO

BACKGROUND: White spotting of the coat is a characteristic trait of various domestic species including cattle and other mammals. It is a hallmark of Holstein-Friesian cattle, and several previous studies have detected genetic loci with major effects for white spotting in animals with Holstein-Friesian ancestry. Here, our aim was to better understand the underlying genetic and molecular mechanisms of white spotting, by conducting the largest mapping study for this trait in cattle, to date. RESULTS: Using imputed whole-genome sequence data, we conducted a genome-wide association analysis in 2973 mixed-breed cows and bulls. Highly significant quantitative trait loci (QTL) were found on chromosomes 6 and 22, highlighting the well-established coat color genes KIT and MITF as likely responsible for these effects. These results are in broad agreement with previous studies, although we also report a third significant QTL on chromosome 2 that appears to be novel. This signal maps immediately adjacent to the PAX3 gene, which encodes a known transcription factor that controls MITF expression and is the causal locus for white spotting in horses. More detailed examination of these loci revealed a candidate causal mutation in PAX3 (p.Thr424Met), and another candidate mutation (rs209784468) within a conserved element in intron 2 of MITF transcripts expressed in the skin. These analyses also revealed a mechanistic ambiguity at the chromosome 6 locus, where highly dispersed association signals suggested multiple or multiallelic QTL involving KIT and/or other genes in this region. CONCLUSIONS: Our findings extend those of previous studies that reported KIT as a likely causal gene for white spotting, and report novel associations between candidate causal mutations in both the MITF and PAX3 genes. The sizes of the effects of these QTL are substantial, and could be used to select animals with darker, or conversely whiter, coats depending on the desired characteristics.

2.
Genet Sel Evol ; 51(1): 3, 2019 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-30678637

RESUMO

BACKGROUND: Over many years, artificial selection has substantially improved milk production by cows. However, the genes that underlie milk production quantitative trait loci (QTL) remain relatively poorly characterised. Here, we investigate a previously reported QTL located at the CSF2RB locus on chromosome 5, for several milk production phenotypes, to better understand its underlying genetic and molecular causes. RESULTS: Using a population of 29,350 taurine dairy cows, we conducted association analyses for milk yield and composition traits, and identified highly significant QTL for milk yield, milk fat concentration, and milk protein concentration. Strikingly, protein concentration and milk yield appear to show co-located yet genetically distinct QTL. To attempt to understand the molecular mechanisms that might be mediating these effects, gene expression data were used to investigate eQTL for 11 genes in the broader interval. This analysis highlighted genetic impacts on CSF2RB and NCF4 expression that share similar association signatures to those observed for lactation QTL, strongly implicating one or both of these genes as responsible for these effects. Using the same gene expression dataset representing 357 lactating cows, we also identified 38 novel RNA editing sites in the 3' UTR of CSF2RB transcripts. The extent to which two of these sites were edited also appears to be genetically co-regulated with lactation QTL, highlighting a further layer of regulatory complexity that involves the CSF2RB gene. CONCLUSIONS: This locus presents a diversity of molecular and lactation QTL, likely representing multiple overlapping effects that, at a minimum, highlight the CSF2RB gene as having a causal role in these processes.


Assuntos
Bovinos/genética , Subunidade beta Comum dos Receptores de Citocinas/genética , Lactação/genética , Fenótipo , Locos de Características Quantitativas , Regiões 3' não Traduzidas , Animais , Subunidade beta Comum dos Receptores de Citocinas/metabolismo , Feminino , Masculino , Leite/metabolismo , Fosfoproteínas/genética
3.
RNA ; 25(3): 319-335, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30530731

RESUMO

Post-transcriptional RNA editing may regulate transcript expression and diversity in cells, with potential impacts on various aspects of physiology and environmental adaptation. A small number of recent genome-wide studies in Drosophila, mouse, and human have shown that RNA editing can be genetically modulated, highlighting loci that quantitatively impact editing of transcripts. The potential gene expression and physiological consequences of these RNA-editing quantitative trait loci (edQTL), however, are almost entirely unknown. Here, we present analyses of RNA editing in a large domestic mammal (Bos taurus), where we use whole-genome and high-depth RNA sequencing to discover, characterize, and conduct genetic mapping studies of novel transcript edits. Using a discovery population of nine deeply sequenced cows, we identify 2413 edit sites in the mammary transcriptome, the majority of which are adenosine to inosine edits (98.6%). Most sites are predicted to reside in double-stranded secondary structures (85.1%), and quantification of the rates of editing in an additional 355 cows reveals editing is negatively correlated with gene expression in the majority of cases. Genetic analyses of RNA editing and gene expression highlight 152 cis-regulated edQTL, of which 15 appear to cosegregate with expression QTL effects. Trait association analyses in a separate population of 9989 lactating cows also shows 12 of the cis-edQTL coincide with at least one cosegregating lactation QTL. Together, these results enhance our understanding of RNA-editing dynamics in mammals, and suggest mechanistic links by which loci may impact phenotype through RNA editing mediated processes.


Assuntos
Regulação da Expressão Gênica , Mamíferos/genética , Edição de RNA , Animais , Sequência de Bases , Mapeamento Cromossômico , Biologia Computacional/métodos , Sequência Consenso , Estudo de Associação Genômica Ampla , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Locos de Características Quantitativas , Característica Quantitativa Herdável
4.
BMC Genomics ; 18(1): 968, 2017 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-29246110

RESUMO

BACKGROUND: Lactose provides an easily-digested energy source for neonates, and is the primary carbohydrate in milk in most species. Bovine lactose is also a key component of many human food products. However, compared to analyses of other milk components, the genetic control of lactose has been little studied. Here we present the first GWAS focussed on analysis of milk lactose traits. RESULTS: Using a discovery population of 12,000 taurine dairy cattle, we detail 27 QTL for lactose concentration and yield, and subsequently validate the effects of 26 of these loci in a distinct population of 18,000 cows. We next present data implicating causative genes and variants for these QTL. Fine mapping of these regions using imputed, whole genome sequence-resolution genotypes reveals protein-coding candidate causative variants affecting the ABCG2, DGAT1, STAT5B, KCNH4, NPFFR2 and RNF214 genes. Eleven of the remaining QTL appear to be driven by regulatory effects, suggested by the presence of co-locating, co-segregating eQTL discovered using mammary RNA sequence data from a population of 357 lactating cows. Pathway analysis of genes representing all lactose-associated loci shows significant enrichment of genes located in the endoplasmic reticulum, with functions related to ion channel activity mediated through the LRRC8C, P2RX4, KCNJ2 and ANKH genes. A number of the validated QTL are also found to be associated with additional milk volume, fat and protein phenotypes. CONCLUSIONS: Overall, these findings highlight novel candidate genes and variants involved in milk lactose regulation, whose impacts on membrane transport mechanisms reinforce the key osmo-regulatory roles of lactose in milk.


Assuntos
Lactose/metabolismo , Proteínas de Membrana Transportadoras/genética , Leite/metabolismo , Locos de Características Quantitativas , Alelos , Animais , Bovinos , Feminino , Expressão Gênica , Variação Genética , Estudo de Associação Genômica Ampla , Transporte de Íons/genética , Lactação/genética , Fenótipo , Polimorfismo de Nucleotídeo Único , Análise de Sequência de DNA , Análise de Sequência de RNA
5.
Sci Rep ; 7: 44793, 2017 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-28322319

RESUMO

A major pleiotropic quantitative trait locus (QTL) located at ~25 Mbp on bovine chromosome 14 affects a myriad of growth and developmental traits in Bos taurus and indicus breeds. These QTL have been attributed to two functional variants in the bidirectional promoter of PLAG1 and CHCHD7. Although PLAG1 is a good candidate for mediating these effects, its role remains uncertain given that these variants are also associated with expression of five additional genes at the broader locus. In the current study, we conducted expression QTL (eQTL) mapping of this region using a large, high depth mammary RNAseq dataset representing 375 lactating cows. Here we show that of the seven previously implicated genes, only PLAG1 and LYN are differentially expressed by QTL genotype, and only PLAG1 bears the same association signature of the growth and body weight QTLs. For the first time, we also report significant association of PLAG1 genotype with milk production traits, including milk fat, volume, and protein yield. Collectively, these data strongly suggest PLAG1 as the causative gene underlying this diverse range of traits, and demonstrate new effects for the locus on lactation phenotypes.


Assuntos
Peso Corporal/genética , Bovinos/genética , Proteínas de Ligação a DNA/genética , Pleiotropia Genética , Leite/química , Animais , Cromossomos de Mamíferos/genética , Indústria de Laticínios , Regulação da Expressão Gênica , Estudo de Associação Genômica Ampla , Polimorfismo de Nucleotídeo Único/genética , Locos de Características Quantitativas/genética , Característica Quantitativa Herdável , Reprodutibilidade dos Testes
6.
J Cell Physiol ; 232(8): 2075-2082, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27608413

RESUMO

To examine tight junction protein abundance and apoptosis of epithelial cells at the onset of involution in rodent mammary glands, milk accumulation and mammary engorgement were induced by teat-sealing with an adhesive for 0, 6, 12, 18, 24, and 36 h (n = 6 per group) at peak lactation. In non-sealed control glands, histological analysis confirmed a lactating phenotype, indicating suckling by pups throughout the experiment. In contrast, alveoli of teat-sealed glands were distended within 6 h, with maximal luminal size observed by 12 h of non-suckling. By 18 h following teat-sealing, an involuting phenotype was observed, indicated by alveolar lumina engorged with milk vesicles and increased leukocytes. Relative to non-sealed glands, mammary apoptosis was increased in engorged glands 18 h following teat-sealing. The abundance of ZO-1 and occludin proteins was decreased in engorged glands by 12 and 18 h, respectively, following teat-sealing. In contrast, the claudin-1 22 kDa band was increased by 6 h and peaked at 12-18 h, whereas the 28 kDa band declined by 36 h, relative to controls. There were no temporal changes in ZO-1, occludin, and claudin-1 22 kDa proteins within control glands, although there were minor differences in claudin-1 28 kDa. These data indicate that intramammary milk accumulation due to cessation of milk removal is associated with mammary apoptosis. The apoptotic event is preceded by a rapid loss of abundance of ZO-1, occludin and an initial increase in claudin-1. The loss of cell-cell communication may initiate involution and apoptosis of mammary epithelial cells and is a localized intramammary event, occurring only in non-suckled glands. J. Cell. Physiol. 232: 2075-2082, 2017. © 2016 Wiley Periodicals, Inc.


Assuntos
Apoptose , Células Epiteliais/metabolismo , Lactação , Glândulas Mamárias Animais/metabolismo , Proteínas de Junções Íntimas/metabolismo , Junções Íntimas/metabolismo , Desmame , Animais , Claudina-1/metabolismo , Células Epiteliais/patologia , Feminino , Glândulas Mamárias Animais/patologia , Ocludina/metabolismo , Fenótipo , Gravidez , Ratos Sprague-Dawley , Transdução de Sinais , Junções Íntimas/patologia , Fatores de Tempo , Proteína da Zônula de Oclusão-1/metabolismo
7.
Sci Rep ; 6: 25376, 2016 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-27146958

RESUMO

The mammary gland is a prolific lipogenic organ, synthesising copious amounts of triglycerides for secretion into milk. The fat content of milk varies widely both between and within species, and recent independent genome-wide association studies have highlighted a milk fat percentage quantitative trait locus (QTL) of large effect on bovine chromosome 5. Although both EPS8 and MGST1 have been proposed to underlie these signals, the causative status of these genes has not been functionally confirmed. To investigate this QTL in detail, we report genome sequence-based imputation and association mapping in a population of 64,244 taurine cattle. This analysis reveals a cluster of 17 non-coding variants spanning MGST1 that are highly associated with milk fat percentage, and a range of other milk composition traits. Further, we exploit a high-depth mammary RNA sequence dataset to conduct expression QTL (eQTL) mapping in 375 lactating cows, revealing a strong MGST1 eQTL underpinning these effects. These data demonstrate the utility of DNA and RNA sequence-based association mapping, and implicate MGST1, a gene with no obvious mechanistic relationship to milk composition regulation, as causally involved in these processes.


Assuntos
Estudo de Associação Genômica Ampla/métodos , Glutationa Transferase/genética , Leite/química , Locos de Características Quantitativas , Animais , Teorema de Bayes , Bovinos , Mapeamento Cromossômico/veterinária , Cromossomos de Mamíferos/genética , Estudo de Associação Genômica Ampla/veterinária , Polimorfismo de Nucleotídeo Único , Análise de Sequência de DNA/veterinária , Análise de Sequência de RNA/veterinária
8.
Sci Rep ; 5: 8484, 2015 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-25719731

RESUMO

Selective breeding has strongly reduced the genetic diversity in livestock species, and contemporary breeding practices exclude potentially beneficial rare genetic variation from the future gene pool. Here we test whether important traits arising by new mutations can be identified and rescued in highly selected populations. We screened milks from 2.5 million cows to identify an exceptional individual which produced milk with reduced saturated fat content, and improved unsaturated and omega-3 fatty acid concentrations. The milk traits were transmitted dominantly to her offspring, and genetic mapping and genome sequencing revealed a new mutation in a previously unknown splice enhancer of the DGAT1 gene. Homozygous carriers show features of human diarrheal disorders, and may be useful for the development of therapeutic strategies. Our study demonstrates that high-throughput phenotypic screening can uncover rich genetic diversity even in inbred populations, and introduces a novel strategy to develop novel milks with improved nutritional properties.


Assuntos
Diacilglicerol O-Aciltransferase/genética , Leite/metabolismo , Mutação de Sentido Incorreto , Animais , Sequência de Bases , Bovinos/genética , Ácidos Graxos/biossíntese , Feminino , Estudos de Associação Genética , Metabolismo dos Lipídeos/genética , Masculino , Linhagem , Fenótipo , Polimorfismo de Nucleotídeo Único
9.
Nat Commun ; 5: 5861, 2014 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-25519203

RESUMO

Lactation, hair development and homeothermy are characteristic evolutionary features that define mammals from other vertebrate species. Here we describe the discovery of two autosomal dominant mutations with antagonistic, pleiotropic effects on all three of these biological processes, mediated through the prolactin signalling pathway. Most conspicuously, mutations in prolactin (PRL) and its receptor (PRLR) have an impact on thermoregulation and hair morphology phenotypes, giving prominence to this pathway outside of its classical roles in lactation.


Assuntos
Regulação da Temperatura Corporal/genética , Cabelo/metabolismo , Lactação/genética , Mutação , Prolactina/genética , Transdução de Sinais , Sequência de Aminoácidos , Animais , Sequência de Bases , Temperatura Corporal , Bovinos , Feminino , Expressão Gênica , Pleiotropia Genética , Genótipo , Cabelo/ultraestrutura , Homeostase , Humanos , Dados de Sequência Molecular , Fenótipo , Prolactina/metabolismo , Receptores da Prolactina/genética , Receptores da Prolactina/metabolismo , Pele/anatomia & histologia , Pele/metabolismo
10.
J Dairy Res ; 81(3): 340-9, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25052435

RESUMO

The objective of this study was to estimate heritability and crossbreeding parameters (breed and heterosis effects) of various fatty acid (FA) concentrations in milk fat of New Zealand dairy cattle. For this purpose, calibration equations to predict concentration of each of the most common FAs were derived with partial least squares (PLS) using mid-infrared (MIR) spectral data from milk samples (n=850) collected in the 2003-04 season from 348 second-parity crossbred cows during peak, mid and late lactation. The milk samples produced both, MIR spectral data and concentration of the most common FAs determined using gas chromatography (GC). The concordance correlation coefficients (CCC) between the concentration of a FA determined by GC and the PLS equation ranged from 0.63 to 0.94, suggesting that some prediction equations can be considered to have substantial predictive ability. The PLS calibration equations were then used to predict the concentration of each of the fatty acids in 26,769 milk samples from 7385 cows that were herd-tested during the 2007-08 season. Data were analysed using a single-trait repeatability animal model. Shorter chain FA (16:0 and below) were significantly higher (P<0.05) in Jersey cows, while longer chain, including unsaturated longer chain FA were higher in Holstein-Friesian cows. The estimates of heritabilities ranged from 0.17 to 0.41 suggesting that selective breeding could be used to ensure milk fat composition stays aligned to consumer, market and manufacturing needs.


Assuntos
Bovinos/genética , Ácidos Graxos/análise , Leite/química , Animais , Cromatografia Gasosa/veterinária , Feminino , Hibridização Genética/genética , Característica Quantitativa Herdável , Espectrofotometria Infravermelho/veterinária
11.
PLoS One ; 9(1): e85757, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24465687

RESUMO

Milk is composed of a complex mixture of lipids, proteins, carbohydrates and various vitamins and minerals as a source of nutrition for young mammals. The composition of milk varies between individuals, with lipid composition in particular being highly heritable. Recent reports have highlighted a region of bovine chromosome 27 harbouring variants affecting milk fat percentage and fatty acid content. We aimed to further investigate this locus in two independent cattle populations, consisting of a Holstein-Friesian x Jersey crossbreed pedigree of 711 F2 cows, and a collection of 32,530 mixed ancestry Bos taurus cows. Bayesian genome-wide association mapping using markers imputed from the Illumina BovineHD chip revealed a large quantitative trait locus (QTL) for milk fat percentage on chromosome 27, present in both populations. We also investigated a range of other milk composition phenotypes, and report additional associations at this locus for fat yield, protein percentage and yield, lactose percentage and yield, milk volume, and the proportions of numerous milk fatty acids. We then used mammary RNA sequence data from 212 lactating cows to assess the transcript abundance of genes located in the milk fat percentage QTL interval. This analysis revealed a strong eQTL for AGPAT6, demonstrating that high milk fat percentage genotype is also additively associated with increased expression of the AGPAT6 gene. Finally, we used whole genome sequence data from six F1 sires to target a panel of novel AGPAT6 locus variants for genotyping in the F2 crossbreed population. Association analysis of 58 of these variants revealed highly significant association for polymorphisms mapping to the 5'UTR exons and intron 1 of AGPAT6. Taken together, these data suggest that variants affecting the expression of AGPAT6 are causally involved in differential milk fat synthesis, with pleiotropic consequences for a diverse range of other milk components.


Assuntos
Bovinos/genética , Variação Genética , Glicerol-3-Fosfato O-Aciltransferase/genética , Lipogênese/genética , Leite/metabolismo , Animais , Sequência de Bases , Cromossomos de Mamíferos/genética , Cruzamentos Genéticos , Feminino , Estudo de Associação Genômica Ampla , Genótipo , Lactação/genética , Lipídeos/genética , Masculino , Glândulas Mamárias Animais/metabolismo , Dados de Sequência Molecular , Fenótipo , Locos de Características Quantitativas/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
12.
J Proteomics ; 75(14): 4429-35, 2012 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-22554911

RESUMO

The liver and the mammary gland have complementary metabolic roles during lactation. Glucose synthesized by the liver is released into the circulation and is taken up by the mammary gland where major metabolic products of glucose include milk sugar (lactose) and the glycerol backbone of milk fat (triglycerides). Hepatic synthesis of glucose is often accompanied by ß-oxidation in that organ to provide energy for glucose synthesis, while mammary gland synthesizes rather than oxidizes fat during lactation. We have therefore compared enzyme abundances between the liver and mammary gland of lactating Friesian cows where metabolic output is well established. Quantitative differences in protein amount were assessed using two-dimensional differential in-gel electrophoresis. As predicted, the abundances of enzymes catalysing gluconeogenesis and ß-oxidation were greatest in the liver, and enzyme abundances in mammary tissue were consistent with fat synthesis rather than ß-oxidation.


Assuntos
Bovinos/metabolismo , Lactação/metabolismo , Fígado/metabolismo , Glândulas Mamárias Animais/metabolismo , Proteoma/metabolismo , Animais , Feminino , Especificidade de Órgãos/fisiologia
13.
Nat Genet ; 43(5): 405-13, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21516082

RESUMO

We report mapping of a quantitative trait locus (QTL) with a major effect on bovine stature to a ∼780-kb interval using a Hidden Markov Model-based approach that simultaneously exploits linkage and linkage disequilibrium. We re-sequenced the interval in six sires with known QTL genotype and identified 13 clustered candidate quantitative trait nucleotides (QTNs) out of >9,572 discovered variants. We eliminated five candidate QTNs by studying the phenotypic effect of a recombinant haplotype identified in a breed diversity panel. We show that the QTL influences fetal expression of seven of the nine genes mapping to the ∼780-kb interval. We further show that two of the eight candidate QTNs, mapping to the PLAG1-CHCHD7 intergenic region, influence bidirectional promoter strength and affect binding of nuclear factors. By performing expression QTL analyses, we identified a splice site variant in CHCHD7 and exploited this naturally occurring null allele to exclude CHCHD7 as single causative gene.


Assuntos
Bovinos/anatomia & histologia , Bovinos/genética , Variação Genética , Alelos , Animais , Sequência de Bases , Mapeamento Cromossômico , Cruzamentos Genéticos , Primers do DNA/genética , Feminino , Estudo de Associação Genômica Ampla , Haplótipos , Desequilíbrio de Ligação , Masculino , Fases de Leitura Aberta , Polimorfismo de Nucleotídeo Único , Regiões Promotoras Genéticas , Locos de Características Quantitativas , Sítios de Splice de RNA , Regulon , Homologia de Sequência do Ácido Nucleico
14.
J Mammary Gland Biol Neoplasia ; 12(4): 237-47, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17992474

RESUMO

Key developments in the understanding of the immune functions of milk and colostrum are reviewed, focusing on their proteinaceous components. The topics covered include the immunoglobulins, immune cells, immunomodulatory substances, and antimicrobial proteins. The contributions of new technologies and the introduction of fresh approaches from other fields are highlighted, as are the contributions that mammary biology research has made to the development of other fields. Finally, a summary of some current outstanding questions and likely future directions of the field are given.


Assuntos
Colostro/imunologia , Leite Humano/imunologia , Leite/imunologia , Animais , História do Século XIX , História do Século XX , Humanos , Imunoglobulinas/imunologia , Imunoglobulinas/metabolismo , Leite/história
15.
J Proteome Res ; 6(1): 207-15, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17203965

RESUMO

Besides providing nutrition to the newborn, milk also protects the neonate and the mammary gland against infection. As well as the six major proteins, bovine milk contains minor proteins, not all of which have been characterized. In this study, we have subjected bovine skim milk, whey, and milk fat globule membrane (MFGM) fractions to both direct liquid chromatography-tandem mass spectrometry (LC-MS/MS), and two-dimensional electrophoresis (2-DE) followed by matrix assisted laser desorption ionization-time-of-flight (MALDI-TOF) mass spectrometry (MS) of individual protein spots to better characterize the repertoire of minor milk proteins, particularly those involved with host defense. Milk from peak lactation as well as during the period of colostrum formation and during mastitis were analyzed to gain a more complete sampling of the milk proteome. In total, 2903 peptides were detected by LC-MS and 2770 protein spots by 2-DE. From these, 95 distinct gene products were identified, comprising 53 identified through direct LC-MS/MS and 57 through 2-DE-MS. The latter were derived from a total of 363 spots analyzed with 181 being successfully identified. At least 15 proteins were identified that are involved in host defense. These results demonstrate that the proteome of milk is more complex than has previously been reported and a significant fraction of minor milk proteins are involved in protection against infection.


Assuntos
Anti-Infecciosos/química , Proteínas do Leite/química , Proteômica/métodos , Animais , Bovinos , Cromatografia Líquida , Colostro/metabolismo , Eletroforese em Gel Bidimensional , Glicolipídeos/metabolismo , Glicoproteínas/metabolismo , Sistema Imunitário , Espectrometria de Massas , Proteínas do Leite/metabolismo , Ciências da Nutrição , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Proteínas do Soro do Leite
16.
Proteomics ; 6(21): 5826-33, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17001600

RESUMO

Previous investigations of bovine seminal plasma (BSP) have revealed the identities of the three major proteins, BSP-PDC109, BSP-A3 and BSP-30 kDa, which together constitute about half of the total protein, as well as about 30 of the minor proteins. Analyses of BSP by 2-DE have revealed about 250 protein spots, suggesting that much of the BSP proteome remains undescribed. In this study, BSP has been analyzed by 2-D LC-based and SDS-PAGE-based proteomic methods. Ninety-nine proteins were identified, including 49 minor proteins that have not previously been described in seminal plasma of any species.


Assuntos
Proteoma/análise , Proteômica/métodos , Sêmen/química , Proteínas de Plasma Seminal/química , Animais , Bovinos , Cromatografia Líquida , Bases de Dados Factuais , Bases de Dados de Proteínas , Eletroforese em Gel Bidimensional , Eletroforese em Gel de Poliacrilamida , Masculino , Peso Molecular , Proteínas de Plasma Seminal/metabolismo , Coloração e Rotulagem
17.
Mycoses ; 48(2): 95-100, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15743425

RESUMO

Reports about the safe and successful intravenous (i.v.) use of garlic derivatives in China against invasive fungal infections have been made, but little has been done to seriously investigate the in vivo use of these derivatives in the West. Laboratories have demonstrated impressive in vitro MICs using allitridium, one of these derivatives, against a range of medically important fungi. In addition, it has been demonstrated that allitridium shows in vitro synergy with amphotericin B, one of the main i.v. antifungal agents. Some of the breakdown products of allicin, the main parent antifungal compound in garlic, have been investigated for their general antimicrobial, anticancer and anticholesterol properties, and it appears that there is a common mode of action that underlies these activities. It appears that these small molecules have the ability to cross cell membranes and combine with sulfur-containing molecular groups in amino acids and proteins, thus interfering with cell metabolism. It has been suggested that the reason human cells are not poisoned by allicin derivatives is that they contain glutathione, a sulfur-containing amino acid that combines with the allicin derivative, thus preventing cell damage. In addition to their biochemical mechanism, these derivatives appear to stimulate cellular immunity, an important ability lacking in conventional antifungal chemotherapy. These derivatives appear to be safe, cheap, wide-spectrum and immunostimulatory, as well as possibly synergistic with conventional antifungal therapy, making them ideal candidates for investigation into their use as prophylactic antifungal agents.


Assuntos
Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Fungos/efeitos dos fármacos , Micoses/prevenção & controle , Ácidos Sulfínicos/farmacologia , Ácidos Sulfínicos/uso terapêutico , Anfotericina B/farmacologia , Anfotericina B/uso terapêutico , Antifúngicos/metabolismo , Sinergismo Farmacológico , Quimioterapia Combinada , Humanos , Imunidade Celular/efeitos dos fármacos , Micoses/microbiologia , Ácidos Sulfínicos/metabolismo
18.
J Cell Physiol ; 200(2): 318-25, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15174102

RESUMO

The mechanisms regulating involution of mammary glands after weaning are not clear, but engorgement with milk is a key trigger. Many cell types require to be anchored to an extracellular matrix (ECM) as a prerequisite for survival and this is achieved via intregrins binding to specific motifs and signalling their attachment, intracellularly, via focal adhesion kinase (FAK). We sought to determine firstly, if expression of beta1-integrin and FAK is reduced during the first stage of involution. Expression of beta1-integrin and FAK was significantly reduced at 6 h after sealing teats and this was accompanied with a decreased abundance of cytochrome C in mitochondria. Secondly, we sought to determine if expression of beta1-integrin and FAK was restored during the first, partially reversible stage of involution (at 24 h), but not during the second irreversible stage, which occurs after 72 h. Re-suckling restored full expression of the 80 kDa fragment of FAK, but not of the 125 kDa protein or beta1-integrin at 24 h after weaning. Re-suckling did not restore expression of either peptide after 72 h. Changes in expression of cytochrome C and pro-caspase-3 (apoptotic markers) were similar to that of the 80 kDa fragment of FAK. These data suggest that epithelial cells can restore partial contact with their basement membrane during the first, reversible stage, but not during the second irreversible stage of involution. We speculate that decreased contact between epithelial cells and their basement membrane initiates apoptosis in mammary glands at weaning. This process begins within 6 h of pup withdrawal.


Assuntos
Células Epiteliais/metabolismo , Integrina beta1/metabolismo , Glândulas Mamárias Animais/metabolismo , Glândulas Mamárias Animais/fisiologia , Proteínas Tirosina Quinases/metabolismo , Animais , Apoptose , Western Blotting , Caspase 3 , Caspases/análise , Citocromos c/metabolismo , Feminino , Quinase 1 de Adesão Focal , Proteína-Tirosina Quinases de Adesão Focal , Imuno-Histoquímica , Integrina beta1/genética , Lactação , Glândulas Mamárias Animais/citologia , Mitocôndrias/enzimologia , Proteínas Tirosina Quinases/genética , Ratos , Ratos Sprague-Dawley
19.
J Dairy Res ; 71(2): 175-81, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15190945

RESUMO

A study was undertaken in cattle to evaluate changes in milk L-lactate in relation to mastitis. A healthy, rear quarter of the udder of each of ten cows in mid-lactation was infused with 1000 colony-forming units (cfu) of Streptococcus uberis following an afternoon milking. Foremilk samples were taken at each milking from control and treated quarters and antibiotic treatment was applied following the onset of clinical mastitis or after 72 h. One cow did not become infected. Six quarters showed clinical symptoms of mastitis within 24-40 h and this was associated with a more than 30-fold increase in milk L-lactate (to 3.3 mM) and an increase in somatic cell count (SCC) from 4.5 x 10(3) to 1 x 10(7) cells/ml. Three cows were subclinical, with cell counts ranging from 1.5 x 10(6) to 1 x 10(7) cells/ml. In these animals, milk lactate ranged from 0.7 to 1.5 mM in the infected quarters up to 40 h post-infection, compared with less than 0.1 mM in control quarters. Milk was examined from 137 cows in mid-lactation which were known to have mastitis. Foremilk samples were taken aseptically from control and infected quarters of cows on commercial farms. Mean milk L-lactate concentrations and SCC were 0.14 +/- 0.02 mM and 1.85 +/- 0.3 x 10(5) cells/ml, respectively, in control (bacteriologically negative) samples. However, L-lactate concentrations exceeded 2.5 mM in the presence of some types of infection, the level of the lactate response being closely related to the impact of the infection on SCC. L-Lactate concentrations were relatively elevated in milk samples taken post partum, declining from 0.8 to 0.14 mM oyer the first few days of lactation. In conclusion, milk L-lactate has potential as an indicator of clinical and subclinical mastitis in dairy cows.


Assuntos
Ácido Láctico/análise , Mastite Bovina/metabolismo , Leite/química , Animais , Apolipoproteínas/análise , Bovinos , Contagem de Células , Feminino , Mastite Bovina/microbiologia , Leite/citologia , Potássio/análise , Proteína Amiloide A Sérica/análise , Sódio/análise , Infecções Estreptocócicas
20.
J Antimicrob Chemother ; 51(3): 593-7, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12615859

RESUMO

The in vitro susceptibility of 20 medical isolates of Scedosporium prolificans to ajoene, allitridium and raw garlic extract derived from cloves of garlic (Allium sativum) was tested using the NCCLS reference method (with minor modifications) for broth microdilution. The results demonstrate that both garlic derivatives and raw garlic extract appear to have in vitro activity against S. prolificans.


Assuntos
Compostos Alílicos/farmacologia , Antifúngicos/farmacologia , Dissulfetos/farmacologia , Alho , Extratos Vegetais/farmacologia , Scedosporium/efeitos dos fármacos , Sulfetos/farmacologia , Antifúngicos/isolamento & purificação , Humanos , Testes de Sensibilidade Microbiana/estatística & dados numéricos , Extratos Vegetais/isolamento & purificação , Estruturas Vegetais , Scedosporium/isolamento & purificação
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