Project description:Genome-wide gene expression and DNA methylation reveals Genetic and Epigenetic differences in cloned piglets and conventionally bred normal piglets (MeDIP-Seq)
Project description:Genome-wide gene expression and DNA methylation reveals Genetic and Epigenetic differences in cloned piglets and conventionally bred normal piglets (RNA-Seq)
Project description:Weaning is a very critical period for piglets, typically accompanied by lower feed intake, weight loss after weaning and increased mortality. At weaning, piglets are exposed to many stressors, such as loss of mothering, mixing with other litters, end of lactational immunity, and a change in their environment and gut microbiota. After weaning, morphological and histological changes occur in the small intestine of piglets producing a rapid change of feeding regime which is critical for the immature digestive system. Sixteen female piglets were weaned to assess the effect of sorbic acid supplementation on the small intestine tissue transcriptome. At weaning day (T0), 4 piglets were sacrified and tissue samples collected. The remaining 12 piglets were weighted and randomly assigned to different post weaning (T5) diets. Diet A (n=6) contained 5 g/kg of sorbic acid. Diet B (n=6) is the same as Standard diet. Total RNA was isolated from ileum samples to be analyzed using the a CombiMatrix CustomArrayTM 90K platform . Even though diet had no detectable effect during the first 5 days after weaning, outcomes from this study highlighted some of the response mechanisms to the stress of weaning occurring in the piglet gut. A total of 205 differentially expressed genes were used for functional analysis using bioinformatics through BLAST2GO, Ingenuity Pathway Analysis 8.0, and the Dynamic Impact Aproach (DIA). Bioinformatics analysis revealed that Apoptosis, RIG-I-like and NOD-like receptor signaling were altered as a result of weaning. Results suggest that immune and inflammatory responses were activated and likely are a cause of small intestine atrophy as revealed by a decrease in villus height and villus/crypt ratio. Keywords: weaning, gut, gene expression, sorbic acid, microarray analysis
Project description:Most animals produced by somatic cell nuclear transfer (SCNT) are heteroplasmic for mitochondrial DNA (mtDNA). Oxidative phosphorylation (OXPHOS) in clones therefore requires the coordinated expression of genes encoded by the nuclear DNA and the two sources of mitochondria. Such interaction is rarely studied because most clones are generated using slaughterhouse oocytes of unrecorded origin. Here we traced the maternal lineages of seven diseased and five one-month-old live cloned piglets by sequencing their mtDNA (short SNP information in single mitochondrial gene). Additionally by using a 13K oligonucleotide microarray, we compared the expression profiles of nuclear and mtDNA-encoded genes that are involved in mitochondrial functions and regulation between the cloned groups and their age-matched controls (n=5 per group). We found that the oocytes used to generate the cloned piglets were of either the Large White or Duroc background, and oocyte genetic background was not related to the clones’ survival. Expression profiles of mtDNA-encoded genes in clones and controls showed intermixed clustering patterns without treatment or maternal lineage-dependency. In contract, clones and controls clustered separately for their global and nuclear DNA-encoded mitochondrial genes in the lungs for both the deceased and live groups. Functional annotation of differentially expressed genes encoded by both nuclear and mtDNA revealed abnormal gene expression in the mitochondrial OXPHOS pathway in deceased clones. Among the nine differentially expressed genes of the OXPHOS pathway, seven were down-regulated in deceased clones compared to controls, suggesting deficiencies in mitochondrial functions. Together, these data demonstrate that the coordination of expression of mitochondrial genes encoded by nuclear and mtDNA is disrupted in the lung of diseased clones.
Project description:In this study, we applied the isobaric tags for relative and absolute quantitation (iTRAQ) technique to detect alterations in the proteomic profile of the jejunal mucosa using a porcine model in which piglets were offered the protein-limited (PL) diet. Protein identification and quantification for iTRAQ experiments were performed using ProteinPilot (v4.0.8085) software. The LC-MS/MS data were searched against the UniProtKB (sus scrofa). To minimize the false discovery rate (FDR), a threshold for protein identification was applied, with the confident value > 95% (amount to the confident value “unused ProtScore” > 1.3 in ProteinPilot software), and at least one unique peptide was considered for protein identification. Proteins that were quantified with fold change > 2.0 were considered to be differentially expressed proteins. We identified 5275 proteins, 202 of which were differentially expressed. Furthermore, we adopted function annotation analysis of all identified proteins and function enrichment analysis of all differentially expressed proteins to explore more meaningful proteins and pathways.
Project description:Backgroud:Epigenetic modifications (especially altered DNA methylation) resulting in altered gene expression may be one reason for development failure or the abnormality of the cloned animals, but the underlying mechanism of the abnormal phenotype in the cloned piglets remains unrevealed. Some cloned piglets in our study showed abnormal phenotypes such as big tongue (longer and thicker), limp, and exomphalos, which is similar to the human BWS syndrome. Here we conducted DNA methylation (DNAm) immunoprecipitation binding high throughput sequencing (MeDIP-seq) and RNA sequencing (RNA-seq) of muscle tissues of cloned piglets to investigate the relationship of abnormal DNAm with gene dysregulation and the unusual phenotypes in cloned piglets. Results:Analysis of the methylomes revealed that abnormal cloned piglets suffered more hypomethylated differentially methylated regions (DMRs) than hypermethylated DMRs compared to the normal cloned piglets. The DNAm level in the CpG Island was higher in the abnormal cloned piglets. Some repetitive elements, such as SINE/tRNA-Glu Satellite/centr also showed significant differences. Besides we detected 1,711 differentially expressed genes (DEGs) between the two groups, of which 243 genes also changed methylation level in the abnormal cloned piglets. The altered DNA methylation mainly affected the low and silent expression genes. We also found some interesting pathways and genes, such as MAPK signalling pathway, hypertrophic cardiomyopathy pathway, TPM3 gene and the imprinted gene PLAGL1, which may played important roles in the abnormal phenotype development. Conclusions;The abnormal cloned piglets showed substantial change both in the DNAm and the gene expression levels. Our data may provide new insights into understanding the molecular mechanisms of the reprogramming of genetic information in cloned animals. We dissected the biceps femoris muscle from the abnormal cloned piglets and the normal cloned piglets, and analyzed the difference of MeDIP-seq and RNA-seq between the two groups.