Project description:Goat's alphaS1-casein (CSN1S1) polymorphism has a significant effect on milk protein and lipid composition, which affects the nutritional quality and technological properties of milk. Moreover, this polymorphism has a large impact on the morphology of mammary epithelial cells. To explore the metabolic pathways modulated in relation to this polymorphism, we compared the mammary gene expression profiles of two groups of lactating goats carrying either two reference or two defective alleles, using a bovine oligonucleotide microarray representing 8379 genes. We identified 41 differentially expressed genes between the two genotype groups. In particular, we showed a downregulation of two key lipogenic genes encoding fatty acid synthase and glycerol-3-phosphate acyltransferase in agreement with the low fat concentration associated with CSN1S1 deficiency. In addition, this study highlights changes in the expression level of several genes known to influence membrane fluidity, cell-cell interaction or chromatin organization. Our results open up new fields of investigation on structural modifications associated with CSN1S1 deficiency that could affect mammary gland function. Keywords: SuperSeries This SuperSeries is composed of the following subset Series: GSE6637: Impact of CSN1S1 polymorphism on mammary transcriptome of lactating goats GSE6642: Impact of CSN1S1 polymorphism on mammary transcriptome of food-deprived lactating goats. Refer to individual Series
Project description:Genetic (animal species, breed and genotype) has a considerable effect on milk composition. In particular, goats present a remarkable polymorphism at the alpha-S1-casein (CSN1S1) locus which results in large differences in milk protein content and indirectly in milk fat content and its fatty acids composition. In order to decipher the mammary metabolic pathways involved, we examined the effect of CSN1S1 polymorphism on the expression of 8,379 genes in caprine mammary gland using a bovine oligonucleotide microarray. Six 48-h food-deprived lactating goats were assigned to 2 groups based on their genotype at the CSN1S1 locus: High vs. Low genotype goats carrying, respectively, two reference alleles associated with high CSN1S1 synthesis and two defective alleles associated with low CSN1S1 synthesis. Keywords: Genotype comparison
Project description:Genetic (animal species, breed and genotype) has a considerable effect on milk composition. In particular, goats present a remarkable polymorphism at the alpha-S1-casein (CSN1S1) locus which results in large differences in milk protein content and indirectly in milk fat content and its fatty acids composition. In order to decipher the mammary metabolic pathways involved, we examined the effect of CSN1S1 polymorphism on the expression of 8,379 genes in caprine mammary gland using a bovine oligonucleotide microarray. Six lactating goats fed ad libitum were assigned to 2 groups based on their genotype at the CSN1S1 locus: High vs. Low genotype goats carrying, respectively, two reference alleles associated with high CSN1S1 synthesis and two defective alleles associated with low CSN1S1 synthesis. Keywords: Genotype comparison
Project description:Genetic (animal species, breed and genotype) has a considerable effect on milk composition. In particular, goats present a remarkable polymorphism at the alpha-S1-casein (CSN1S1) locus which results in large differences in milk protein content and indirectly in milk fat content and its fatty acids composition. In order to decipher the mammary metabolic pathways involved, we examined the effect of CSN1S1 polymorphism on the expression of 8,379 genes in caprine mammary gland using a bovine oligonucleotide microarray. Six lactating goats fed ad libitum were assigned to 2 groups based on their genotype at the CSN1S1 locus: High vs. Low genotype goats carrying, respectively, two reference alleles associated with high CSN1S1 synthesis and two defective alleles associated with low CSN1S1 synthesis. Keywords: Genotype comparison 6 slides were performed for a total of 3 independent comparisons (Comp1, Comp2, Comp3): each microarray was co-hybridized with one High CSN1S1 genotype goat sample and one Low CSN1S1 genotype goat sample; each hybridization was repeated in a dye-swap manner for a total of 4 spots per oligonucleotide (2 intra- and 2 inter-slides).
Project description:Genetic (animal species, breed and genotype) has a considerable effect on milk composition. In particular, goats present a remarkable polymorphism at the alpha-S1-casein (CSN1S1) locus which results in large differences in milk protein content and indirectly in milk fat content and its fatty acids composition. In order to decipher the mammary metabolic pathways involved, we examined the effect of CSN1S1 polymorphism on the expression of 8,379 genes in caprine mammary gland using a bovine oligonucleotide microarray. Six 48-h food-deprived lactating goats were assigned to 2 groups based on their genotype at the CSN1S1 locus: High vs. Low genotype goats carrying, respectively, two reference alleles associated with high CSN1S1 synthesis and two defective alleles associated with low CSN1S1 synthesis. Keywords: Genotype comparison 6 slides were performed for a total of 3 independent comparisons (CompA, CompB, CompC): each microarray was co-hybridized with one High CSN1S1 genotype goat sample and one Low CSN1S1 genotype goat sample; each hybridization was repeated in a dye-swap manner for a total of 4 spots per oligonucleotide (2 intra- and 2 inter-slides).
Project description:In dairy ruminants transcriptome profiling has enabled the identification of genes, pathways and regulatory networks activated in mammary tissues during experimental infection by various pathogens, including E. coli, S. aureus and S. uberis. Information in goats are still low and many host-pathogen interaction mechanisms have to be explained. The objectives of the present study were (1) to identify the network of genes that becomes activated in caprine blood and milk somatic cells in early response towards a S. aureus challenge in order to better understand the local and sistemic response and (2) to search any difference in this immune response by using two animal groups belonging to a caprine reference family established based on founders with adverse SCC breeding values.
Project description:Animal nutrition considerably affects milk composition that influences its nutritional quality. Milk component synthesis and secretion by the mammary gland involve the expression of a large number of genes whose nutritional regulation remains poorly defined. In this study, 16 lactating goats received 4 experimental diets differing in either forage to concentrate ratio (high forage, HF, or low forage, LF) supplemented, or not, with lipids (whole rapeseeds, RS, or sunflower oil, SO) in a 4 x 4 Latin Square design. To investigate the pathways regulated by nutrition, we examined the effect of these diets on the expression of approximately 8400 genes in caprine mammary gland using a bovine oligonucleotide microarray. Due to the limited quantity of mammary RNA available, equal amounts of total RNA sample from mammary gland of each goat belonging to the same Latin Square group were mixed together before labeling. Each mammary pooled sample (4 by dietary treatment) was then co-hybridized with a standard reference corresponding to a mixture of purified total RNA from several caprine tissues. Each hybridization was repeated in a dye-swap manner for a total of 32 slides (8 slides and 4 independent comparisons by dietary treatment).
Project description:In dairy ruminants transcriptome profiling has enabled the identification of genes, pathways and regulatory networks activated in mammary tissues during experimental infection by various pathogens, including E. coli, S. aureus and S. uberis. Information in goats are still low and many host-pathogen interaction mechanisms have to be explained. The objectives of the present study were (1) to identify the network of genes that becomes activated in caprine blood and milk somatic cells in early response towards a S. aureus challenge in order to better understand the local and sistemic response and (2) to search any difference in this immune response by using two animal groups belonging to a caprine reference family established based on founders with adverse SCC breeding values. Udders from ten healthy French Alpine goats were infected with S. aureus and samples of blood and milk cells were collected at 0, 24 and 30 hours after infection. Alterations in the transcriptome profile were investigated using a custom bovine DNA microarray containing 43.822 unique gene probes.