Project description:Since the molecular mechanism underlying feed efficiency (FE) in slow-growing chickens is poorly understood. Thus, this study aimed to investigate the proteome differences and possible pathways associated with FE in male slow-growing chicken by using a label-free quantitative proteomic approach. At 10 weeks of ages duodenum samples from six animals (three high-FE and three low-FE chickens) were collected for differential abundant proteins (DAPs), protein networks, functional enrichment and pathway analysis. In this study, we found 40 DAPs significantly associated with FE pathways included glycolysis/gluconeogenesis, peroxisome, oxidative phosphorylation, tight junction, and cysteine and methionine metabolism. Thus, the differences of protein driving those pathways affected the FE potential of slow-growing chicken might be interesting candidate biomarkers for genomic selection of animals with a higher efficient feed utilization.
Project description:Gill transcriptome of fast- and slow-growing mussels reared under continuous food supply was recently analysed in order to ascertain the differential gene expression underlying interindividual differences in growth rate. The present study aims to analyse the gene expression differences between fast- and slow-growing mussels submitted to an air exposure of 8 hours a day during the rearing period. Transcriptome will be also compared with their continuously submerged counterparts in order to analyse the effect of air exposure on the gene expression of fast- and slow-growing individuals.
Project description:Slow-growing Korat chicken (KR) is an alternative to broiler chickens that has been used as a national tool to support smallholder farmers due to a higher selling price of KR meat. However, the individual variability of feed efficiency (FE) within a KR stockbreeding results in a lack of competitiveness. Therefore, improvement of FE of KR is of major importance to improve the profitability of livestock production enterprises. Here, we selected two groups of KR with divergent feed conversion ratios (FCR). We performed RNA-sequencing in order to profile KR jejunal transcriptome and to identify the transcriptional variations and biological pathways implied in response to divergent FCR. The biological pathways involved were revealed by enrichment of the Gene Ontology (GO) terms, and the Kyoto Encyclopedia of Gene and Genome (KEGG) pathways. The results showed that main pathways involved in KR FCR divergence were related to immune response, glutathione metabolism, vitamin transport and metabolism, lipid metabolism, and maturation, development and growth. This is the first study to investigate the molecular genetic mechanisms affecting the FCR values in jejunum of slow-growing chicken. This study will be useful in the line-breeding programs for slow growing chickens to improve FE in the stockbreeding and its profitability.
Project description:Chitin is the second most abundant biopolymer present in soils and is utilized by antibiotic-producing Streptomyces species. Its monomer, N-acetylglucosamine (NAG), regulates the developmental program of the model organism Streptomyces coelicolor. NAG blocks differentiation when growing on rich medium whilst it promotes development on poor culture media. We report here the negative effect of NAG on tacrolimus (FK506) production in Streptomyces tsukubaensis NRRL 18488 growing on a defined rich medium. Using microarrays technology, we found that GlcNAc represses the transcription of fkbN, encoding the main transcriptional activator of the tacrolimus biosynthetic cluster, and of ppt1, encoding a phosphopantheteinyltransferase involved in tacrolimus biosynthesis. On the contrary, NAG stimulated transcription of genes related to amino acid and nucleotide biosynthesis, DNA replication, RNA translation, glycolysis, pyruvate metabolism, and key gene members of the PHO regulon. The results obtained support those previously reported for S. coelicolor, but some important differences were observed
Project description:When Trypanosoma brucei parasites, the causative agent of sleeping sickness, colonize the adipose tissue, they rewire gene expression. Whether this adaptation affects population behavior and disease treatment remained unknown. By using a mathematical model, we estimate that the population of adipose tissue forms (ATFs) proliferates slower than blood parasites. Analysis of the ATFs proteome, measurement of protein synthesis and proliferation rates confirm that the ATFs divide on average every 12hr, instead of 6hr in the blood. Importantly, the population of ATFs is heterogeneous with parasites doubling times ranging between 5hr and 35hr. Slow-proliferating parasites remain capable of reverting to the fast proliferation profile in blood conditions. Intravital imaging shows that ATFs are refractory to drug treatment. We propose that in adipose tissue, a subpopulation of T. brucei parasites acquire a slow growing behavior, which contributes to disease chronicity and treatment failure.
Project description:Endogenously determined inter-individual differences in growth rate of bivalve molluscs have been widely analyzed at different organizational levels. Most studies have focused on the characterization of the physiological differences between fast (F) and slow (S) growing individuals. Although several genes have been described to be up regulated on fast growing individuals, the molecular basis underlying the mechanisms at the origin of growth variation is still poorly understood. In the present study we reared mussel spat of the species Mytilus galloprovincialis under diets below the pseudofaeces threshold (BP) and above the pseudofaeces threshold (AP). After 3 months, F and S mussels on each condition were selected, so that 4 experimental groups were obtained: FBP, SBP, FAP and SAP. We hypothesized that nurturing conditions during their growing period would modify the molecular basis of growth rate differences. However, results of feeding experiments showed that F mussels displayed higher clearance and ingestion rates and higher efficiencies of food selection prior to ingestion, as well as higher gill surface areas, irrespective of the rearing nutritional environment. To decipher molecular mechanism at the origin of growth variation, gills of the 4 mussel groups were dissected, and used for transcriptome analysis with a custom Agilent single channel microarray. Gene expression analysis revealed i) a low number (12) of genes differentially expressed associated to maintenance condition differences and ii) 117 genes differentially expressed when comparing fast and slow growing mussels (FBP + FAP vs. SBP + SAP). We further investigated this comparison: GO terms and KEGG pathway association of the differentially expressed genes allowed us to analyze the functions involved on the differentially expressed encoding. Transcriptomic differences between F and S mussels were mainly based on the up-regulation of response to stimulus, growth and cell activity Biological Process GO terms. Regarding the KEGG terms, carbohydrate metabolism and Krebs cycle were found to be up-regulated in F mussels whereas biosynthetic processes were up-regulated in S mussels. Among the differentially expressed genes that are annotated, the following ones were found to be up regulated in F mussels: i) Mucin, related to mucus secretion, known to be crucial in food acquisition and pre-ingestive selection processes in bivalves, ii) genes related to growth such as Myostatin or Insulin-like growth factor, iii) genes involved in feeding activity, such as Fibrocystin or Dynein and iv) genes involved in the energetic metabolism; Citrate synthase. S mussels mainly over-expressed genes related to immune system and defence (Leucine-rich repeat-containing protein, Metalloendopeptidase, Small heat shock protein 24, Multidrug resistance,…).The present results suggest that differences in feeding activity and in the allocation of metabolic energy between growth groups could account for the differences in growth rate in spat of Mytilus galloprovincialis. In accordance with their higher feeding rates and growth, fast growing mussels were found to mainly over-express genes involved in the development and maintenance of such activities, however, slow growing mussels needed to expend energy in immune and defence processes to ensure survival at the expense of growth rate.
Project description:We performed ribosome profiling which is the deep-sequencing of mRNA fragments protected by translating ribosome for two Streptomyces species through different growth phases to provide the translatome data