Project description:In the current study, we expanded our previous work to identify miRNAs implicated in the myogenesis regulation through the comparison of miRNAs transcriptome in skeletal muscle tissues between broilers and layers. To address that, we firstly performed Solexa deep sequencing to profile miRNAs expressed in chicken skeletal muscle tissues. Sequence tags analyses not only enable us to report a group of highly abundant known miRNAs expressed in skeletal muscles but most importantly to identify novel putative chicken miRNAs from skeletal muscle tissue. Further miRNA transcriptome comparison and real-time RT-PCR validation experiments revealed seveal differentially expressed miRNAs between broilers and layers.
Project description:Breast muscle myopathies in broilers compromise meat quality and continue to plague the poultry industry. Broiler breast muscle myopathies are characterized by impaired satellite cells (SC)-mediated repair, and localized tissue hypoxia and dysregulation of oxygen homeostasis have been implicated as contributing factors. The present study was designed to test the hypothesis that hypoxia disrupts the behavior of SC essential for multinucleated myotube formation in vitro, and to determine the extent to which effects are reversed by restoration of oxygen tension. Primary SC was isolated from pectoralis major of young (5 d) Cobb 700 chicks and maintained in growth conditions or induced to differentiate under normoxic (20% O2) or hypoxic (1% O2) conditions for up to 48 h. Hypoxia enhanced SC proliferation while inhibiting myogenic potential, with decreased fusion index and suppressed myotube formation. Reoxygenation after hypoxia partially reversed effects on both proliferation and myogenesis. Western blotting showed that hypoxia diminished myogenin expression, activated AMPK, upregulated proliferation markers, and increased molecular signaling of cellular stress. Hypoxia also promoted accumulation of lipid droplets in myotubes. Targeted RNAseq identified numerous differentially expressed genes across differentiation under hypoxia, including several genes that have been associated with myopathies in vivo. Altogether, these data demonstrate localized hypoxia may influence SC behavior in ways that disrupt muscle repair and promote the formation of myopathies in broilers.
Project description:The genetic closeness and divergent muscle growth rates of broilers and layers make them great models for myogenesis study. In order to discover the molecular mechanisms determining the divergent muscle growth rates and muscle fiber sizes in different chicken lines, we systematically identified differentially expressed genes between broilers and layers during muscle development (postnatal 1 day, 2 weeks, 4 weeks, 6 weeks and 8 weeks) by microarray hybridization experiment. Taken together, 543 differentially expressed probe sets were found between broilers and layers across different developmental stages, including genes related to muscle growth and hypertrophy, fatty acid transportation and metabolism, protein degradation, and several important signaling pathways. The expression profiles of a few differentially expressed genes were highly correlated with the growth rates of broilers and layers. We also identified SNPs within upstream transcription factor binding sites of a few differentially expressed genes, indicating that these SNPs might be the causing factor of the expression differences of these genes between broilers and layers. These studies provided new clues for deciphering mechanisms underlining muscle development and organ size control in different chicken lines, will shed light on the study of human muscle related disease as well. Experiment Overall Design: Pectoralis major muscles were sampled from broilers and layers at indicated developmental stage (postnatal 1 day, 2 weeks, 4 weeks, 6 weeks and 8 weeks). Trizol extraction of total RNA was performed according to the manufacturer's instructions. Biotinylated cRNA were prepared according to the standard Affymetrix protocol from 2 ug total RNA. Affymetrix Gene Chip array hybridization was carried out according to Affymetrix Expression Analysis Technical Manual by GeneTech Biotechnology Limited Company (Shanghai, China). Following labeled cRNA fragmentation, 15 ug of cRNA were hybridized for 16 hr at 45â on Affymetrix Chicken Genome Array. After standard washing and staining, GeneChips were scanned using the Affymetrix GeneChip Scanner 7G.
Project description:The genetic closeness and divergent muscle growth rates of broilers and layers make them great models for myogenesis study. In order to discover the molecular mechanisms determining the divergent muscle growth rates and muscle fiber sizes in different chicken lines, we systematically identified differentially expressed genes between broilers and layers during muscle development (embyonic day 10, 12, 14 and 18) by microarray hybridization experiment.
Project description:The genetic closeness and divergent muscle growth rates of broilers and layers make them great models for myogenesis study. In order to discover the molecular mechanisms determining the divergent muscle growth rates and muscle fiber sizes in different chicken lines, we systematically identified differentially expressed genes between broilers and layers during muscle development (postnatal 1 day, 2 weeks, 4 weeks, 6 weeks and 8 weeks) by microarray hybridization experiment. Taken together, 543 differentially expressed probe sets were found between broilers and layers across different developmental stages, including genes related to muscle growth and hypertrophy, fatty acid transportation and metabolism, protein degradation, and several important signaling pathways. The expression profiles of a few differentially expressed genes were highly correlated with the growth rates of broilers and layers. We also identified SNPs within upstream transcription factor binding sites of a few differentially expressed genes, indicating that these SNPs might be the causing factor of the expression differences of these genes between broilers and layers. These studies provided new clues for deciphering mechanisms underlining muscle development and organ size control in different chicken lines, will shed light on the study of human muscle related disease as well. Keywords: Time-course studies of two different intra-species breeds
Project description:In the current study, we expanded our previous work to identify miRNAs implicated in the myogenesis regulation through the comparison of miRNAs transcriptome in skeletal muscle tissues between broilers and layers. To address that, we firstly performed Solexa deep sequencing to profile miRNAs expressed in chicken skeletal muscle tissues. Sequence tags analyses not only enable us to report a group of highly abundant known miRNAs expressed in skeletal muscles but most importantly to identify novel putative chicken miRNAs from skeletal muscle tissue. Further miRNA transcriptome comparison and real-time RT-PCR validation experiments revealed seveal differentially expressed miRNAs between broilers and layers. Examination of miRNA transcriptome in skeletal muscle of two kinds of chickens
Project description:The genetic closeness and divergent muscle growth rates of broilers and layers make them great models for myogenesis study. In order to discover the molecular mechanisms determining the divergent muscle growth rates and muscle fiber sizes in different chicken lines, we systematically identified differentially expressed genes between broilers and layers during muscle development (embyonic day 10, 12, 14 and 18) by microarray hybridization experiment. Time-course studies of two different intra-species breeds
Project description:Gene expression profiling of clostridium perfringens infection in broilers on medicated and non-medicated diets using chicken 44k agilent microarray. To elucidate molecular and ceelular mechanisms of bacitracin effect on CP infection in chickens by microarray technology.
Project description:White Striping and Wooden Breast (WS/WB) are abnormalities increasingly occurring in the fillets of high breast yield and growth rate chicken hybrids. These defects lead to consistent economic losses for poultry meat industry, as affected broilers fillets present an impaired visual appearance that negatively affects consumers’ acceptability. Previous studies have highlighted in affected fillets a deeply damaged muscle, showing profound inflammation, fibrosis and lipidosis. The present study investigated the differentially expressed genes and pathways linked to the compositional changes observed in WS/WB breast muscles, in order to outline a more complete framework of the gene networks related to the occurrence of this complex pathological picture. The biochemical composition was performed on 20 Pectoralis major samples obtained from high breast yield and growth rate broilers (10 affected vs. 10 normal) and 12 out of the 20 samples were used for the microarray gene expression profiling (6 affected vs. 6 normal). The obtained results indicate strong changes in muscle mineral composition, coupled to an increased deposition of fat. In addition, 204 differentially expressed genes (DEG) were found: 102 up-regulated and 102 down-regulated in affected breasts. The gene expression pathways found more altered in WS/WB muscles are those related to muscle development, polysaccharide metabolic processes, proteoglycans synthesis, inflammation and calcium signaling pathway. On the whole, the findings suggest that a multifactorial and complex etiology is associated with the occurrence of WS/WB muscle abnormalities, contributing to further define the transcription patterns associated to these myopathies.
Project description:Chicken (Gallus gallus) were first domesticated from a wild form called red jungle fowl that still runs wild in most of southeast Asia. After then the grey jungle fowl (G. sonneratii) was hybridized, which was occurred probably about 8,000 years ago, and domestic chickens have been selected to have ideal economic traits such as a meat and a laying breed. In these breeds, a meat breed such as broiler is the most distributed in poultry industry. In addition, calcium is essential for normal cellular function and blood coagulation. However, it caused the hypocalcemia and the hypercalcemia if calcium intake was less and more than adequate calcium intake such as hypocalcemia and hypercalcemia, which is related to hypertension and blood pressure. So, we generated RNA-seq data from nine chicken broilers according to calcium intake (0.8, 1.0 and 1.2percent) for gene expression profiling. As a result, we identified differentially expressed genes (DEGs) using cufflinks (128 DEGs between 0.8 versus 1.0 percent, 141 DEGs between 0.8 versus 1.2 percent and 103 DEGs between 1.0 versus 1.2 percent), also 12 DEGs were identified by generalized linear model (GLM) within edgeR. We identified that these DEGs were related to hypertension and blood pressure through the KEGG pathway enrichment, the co-occurrence and the protein/protein interaction (PPI) network analysis. In summary, the objective of this study was to investigate the influence of increasing calcium intake in chicken broilers kidney. Therefore, we suggested that higher calcium intake than adequate in chicken broilers can caused the hypertension and high blood pressure.