Project description:Tail fat in sheep (Ovis aries), has evolved mainly in response to cold weather for better energy storage. As things stand, too much tail fat in sheep can lead to a reduction in feed utilisation and is also unpopular with consumers due to the excessive fat content in the tail of sheep. Therefore, the need to find the mechanism of tail fat formation is obvious. In this study, we elected to utilise Kazakh sheep, prolific Suffolk sheep, and their hybrid F2 generation as research objects. Sheep transcriptome sequencing technology was employed to screen and explore target candidate genes related to sheep tail fat deposition. Comparison with RNA-seq data from fat-tailed and thin-tailed tissue, the LncRNA-mRNA-miRNA axis was identified as main functional pathway in the formation of fat in tail. Our results offer valuable insights into the fat deposition of sheep and provide a significant genomic resource for future genetic studies and the enhancement of genome-assisted breeding in sheep and other domestic animals.
Project description:Chinese indigenous sheep can be classified into two types according to their tail morphology: fat-rumped and thin-tailed sheep, of which the typical breeds are Altay sheep and Tibetan sheep, respectively. To identify the differentially expressed proteins (DEPs) underlying the phenotypic differences between tail types, we used iTRAQ combined with multi-dimensional liquid chromatography tandem mass spectrometry (LC-MS/MS) technology to detect candidate proteins. We then subjected these to a database search, and identified the DEPs. Finally, bioinformatics technology was used to carry out GO functional and KEGG pathway analyses. A total of 3248 proteins were identified, of which 44 were up-regulated and 40 were down-regulated DEPs. Analyzing their GO function terms and KEGG pathways revealed that the functions of these DEPs are mainly binding, catalytic activity, structural molecule activity, molecular function regulator, and transporter activity. Among the genes encoding the DEPs, APOA2, GALK1, ADIPOQ, and NDUFS4 are associated with fat formation and metabolism.
Project description:Here we present a high-density in situ synthesized microarray for Ovis aries, named Aristaeus, designed by means of a pipeline of software instruments that, starting from non-annotated redundant EST sequences, selects oligonucleotides suitable for in situ generation on chip. The chip was tested by comparing the gene expression profiles of two sheep breeds with different phenotype, Sarda and Gentile di Puglia. We carried out microarray experiments on liver and udder tissues from lactating individuals and identified a relevant number of differentially expressed genes, all involved in metabolism pathways. The results are consistent with literature knowledge, while selected differential gene expressions have been confirmed by quantitative real-time polymerase chain reaction analyses. Tissue samples of liver were collected from 4 lactating individuals of two sheep (Ovis aries) breeds, Gentile di Puglia and Sarda. Biopsies of liver tissue were taken at second lactation stage (first record, stage 01: 6 days after lambing; second record, stage 02: 44 days after lambing) in both breeds. Tissues from liver were immersed in RNAlater (Sigma) immediately after biopsy and stored at -20°C. Samples were pooled by breed and then reverse labeled (cy5 and cy3), resulting in four raw data sets.
Project description:The sheep (Ovis aries) plays a major socio-economic role in the world. Copy number variations (CNVs) are increasingly recognized as a key and potent source of genetic variation and phenotypic diversity, but little is known about the extent to which CNVs contribute to genetic variation in Chinese sheep breeds. Analyses of CNVs in the genomes of eight sheep breeds were performed using the sheep SNP50 BeadChip genotyping array. A total of 111 CNV regions (CNVRs) were obtained from 160 Chinese sheep breeds. These CNVRs covered 13.75 Mb of the sheep genome sequence. A total of 22 Go terms and 17 candidate genes were obtained from the functional analysis. Ten CNVRs were selected for validation, of which 7 CNVRs were further experimentally confirmed by quantitative PCR. Four candidate genes were selected to confirm the results of the functional analysis. These results provide a resource for furthering understanding of ruminant biology, and for further improving the genetic quality of sheep breeds.
Project description:An essential tissue involved in the development and regulation of lipid metabolism in animals is adipose tissue. The “fat-tail” can supply energy for sheep during migration and winter when a low amount of dry matter intake is available. Tail fat content affects meat quality and varies significantly among the different breeds of sheep. Ghezel (fat-tailed) and Zel (thin-tailed) are two important local Iranian sheep breeds that show different patterns of fat storage. The current study presents the transcriptome characterization of tail fat using RNA-sequencing in order to get a better comprehension of the molecular mechanism of lipid storage in the two sheep breeds. The results of sequencing were analyzed with bioinformatics methods, including differentially expressed genes (DEGs) identification, functional enrichment analysis, structural classification of proteins, protein–protein interaction (PPI), network analysis and module analysis. The results revealed a total of332 DEGs between the Zel and Ghezel breed, with78 up-regulated and 254 down-regulated DEGs in the Zel breed. Identification of differential genes showed that some DEGs, such as IL-6, LIPG, SAA1, SOCS3 and HIF-1α, with the largest fold change had close association with lipid deposition. Also, important lipid storage genes such as FASN and SCPEP1 had high levels of expression. Furthermore, functional enrichment analysis revealed some pathways associated with fat deposition, such as “Fatty acid metabolism”, “Fatty acid biosynthesis” and“HIF-1 signaling pathway”. In addition, structural classification of proteins showed major DEGs in transcription factor classes such as JUNB, NR4A3, FOSL1, MAFF, NR4A1, CREB3L1 and ATF3 were up-regulated in the Zel breed. IL-6, JUNB, and related DEGs were up-regulated in the PPI network.HMGCS1, SUCLA2 and STT3B and related DEGs were down-regulated in the PPI network and had high topology scores as hub genes. This implies the DEGs of these modules are important candidate genes for tail fat metabolism and, therefore, can be further studied.
Project description:An essential tissue involved in the development and regulation of lipid metabolism in animals is adipose tissue. The “fat-tail” can supply energy for sheep during migration and winter when a low amount of dry matter intake is available. Tail fat content affects meat quality and varies significantly among the different breeds of sheep. Ghezel (fat-tailed) and Zel (thin-tailed) are two important local Iranian sheep breeds that show different patterns of fat storage. The current study presents the transcriptome characterization of tail fat using RNA-sequencing in order to get a better comprehension of the molecular mechanism of lipid storage in the two sheep breeds. The results of sequencing were analyzed with bioinformatics methods, including differentially expressed genes (DEGs) identification, functional enrichment analysis, structural classification of proteins, protein–protein interaction (PPI), network analysis and module analysis. The results revealed a total of332 DEGs between the Zel and Ghezel breed, with78 up-regulated and 254 down-regulated DEGs in the Zel breed. Identification of differential genes showed that some DEGs, such as IL-6, LIPG, SAA1, SOCS3 and HIF-1α, with the largest fold change had close association with lipid deposition. Also, important lipid storage genes such as FASN and SCPEP1 had high levels of expression. Furthermore, functional enrichment analysis revealed some pathways associated with fat deposition, such as “Fatty acid metabolism”, “Fatty acid biosynthesis” and“HIF-1 signaling pathway”. In addition, structural classification of proteins showed major DEGs in transcription factor classes such as JUNB, NR4A3, FOSL1, MAFF, NR4A1, CREB3L1 and ATF3 were up-regulated in the Zel breed. IL-6, JUNB, and related DEGs were up-regulated in the PPI network.HMGCS1, SUCLA2 and STT3B and related DEGs were down-regulated in the PPI network and had high topology scores as hub genes. This implies the DEGs of these modules are important candidate genes for tail fat metabolism and, therefore, can be further studied.
Project description:Milk and dairy products are an essential food and an economic resource in many countries. Milk component synthesis and secretion by the mammary gland involve expression of a large number of genes whose nutritional regulation remains poorly defined. We aim at understanding the genomic influence on milk quality and synthesis by comparing two sheep breeds, with different milking attitude, Sarda and Gentile di Puglia, using sheep-specific microarray technology. From sheep ESTs deposited at NCBI, we generated the first annotated microarray developed for sheep with a covering of most of the genome. Whole tissue samples of mammary gland were collected from 4 lactating individuals of two sheep (Ovis aries) breeds, Gentile di Puglia and Sarda. Biopsies of lactating mammary tissue were taken at two lactation stages (first record, stage 01: 6 days after lambing; second record, stage 02: 44 days after lambing) in both breeds. Tissues from mammary gland were immersed in RNAlater (Sigma) immediately after biopsy and stored at -20°C.
Project description:Here we present a high-density in situ synthesized microarray for Ovis aries, named Aristaeus, designed by means of a pipeline of software instruments that, starting from non-annotated redundant EST sequences, selects oligonucleotides suitable for in situ generation on chip. The chip was tested by comparing the gene expression profiles of two sheep breeds with different phenotype, Sarda and Gentile di Puglia. We carried out microarray experiments on liver and udder tissues from lactating individuals and identified a relevant number of differentially expressed genes, all involved in metabolism pathways. The results are consistent with literature knowledge, while selected differential gene expressions have been confirmed by quantitative real-time polymerase chain reaction analyses.
Project description:Milk can mediate maternal-neonatal signal transmission by the bioactive component-extracellular vesicles (EVs), which select specific types of miRNA to encapsulate. The miRNA profiling of sheep milk EVs was characterized by sequencing and compared with that of cow milk. Sheep milk EVs contained various small RNAs, including tRNA, Cis-regulatory element, rRNA, snRNA, other Rfam RNA, and miRNA, which held about 36% of all the small RNAs. Totally 84 types of miRNAs were annotated with Ovis aries by miRBase (version 22.0) in sheep milk EVs, with 75 shared types of miRNAs in all samples. Fourteen sheep milk EV-miRNAs in the top 20, occupying 98% of the total expression, were immune-related.