Project description:In this study, two small RNA libraries were constructed using dry period and peak lactation dairy goat mammary gland tissues and sequenced by the Illumina Solexa high-throughput sequencing system. A total of 346 conserved and 95 novel miRNAs were identified in the dairy goat. The expression of miRNAs was confirmed by qRT-PCR in nine tissues and the mammary gland during development cycles. In addition, several candidate miRNAs that may be involved in mammary gland development and lactation were found by the comparison of miRNA expression profiles among different tissue and developmental stages of the mammary gland. This study provides the identification and profile of miRNAs related to the biology of the mammary gland in the dairy goat. The identification of these miRNAs could contribute to understanding the molecular mechanisms of lactation physiology and the development of the mammary gland in the dairy goat.
Project description:We investigated miRNA expression in Holstein dairy cow of mammary gland with different producing quality milk using high-throughput sequence and qRT-PCR techniques. miRNA libraries were constructed from mammary gland tissues taken from a high producing quality milk and a low producing quality milk Holstein dairy cow, the small RNA digitalization analysis based on HiSeq high-throughput sequencing takes the SBS-sequencing by synthesis.The libraries included 4732 miRNAs. A total of 124 miRNAs in the high producing quality milk mammary gland showed significant differences in expression compared to low producing quality milk mammary gland (P<0.05). Conclusion: Our study provides a broad view of the bovine mammary gland small RNA expression profile characteristics. Differences in types and expression levels of miRNAs were observed between high producing quality milk and a low producing quality milk Holstein dairy cow
Project description:We report the application of Solexa high-throuthput sequencing technology for miRNA differential expression profiles. Using an optimized data analysis workflow, we mapped about 30 million sequence reads per sample to Ovis aries genome. The results were validated by qRT-PCR. Our study represents the first detailed analysis of miRNA expression profiles in goat mammary gland tissues, with biologic replicates generated by RNA-seq technology. miRNA expression profiles of goat mammary gland tissues between peak lactation and late lactation were generated by Illumina/Solexa sequencing
Project description:Effect of breed in mid lactation Holstein (H) and Montbéliarde (M) cows on mammary glande miRNA profile. Genetic polymorphisms are known to influence milk production and composition. However, genomic mechanisms involved in the genetic regulation of milk component synthesis are not completely understood. MicroRNAs (miRNA) regulate gene expression. The objective of the present study was to compare mammary gland miRNomes of two dairy cow breeds, Holstein and Montbéliarde, with different dairy performances. Milk, fat, protein, and lactose yields were lower in Montbéliarde than in Holstein cows. MiRNomes obtained using RNA-Seq technology from the mammary glands of Holstein (n = 5) and Montbéliarde (n = 6) lactating cows revealed 623 distinct expressed miRNAs, among which 596 were known and 27 were predicted miRNAs. The comparison of their abundance in the mammary gland of Holstein versus Montbéliarde cows showed 22 differentially expressed miRNAs (Padj ≤ 0.05). Among them, 11 presented a fold change ≥2, with 2 highly expressed miRNAs (miR-100 and miR-146b). Without taking into account the fold change, the differential miRNA with the highest abundance was miR-186, which is known to inhibit cell proliferation and epithelial-to-mesenchymal transition. Data mining showed that the 17 differentially expressed miRNAs with more than 20 reads on average, regulate mammary gland plasticity and may be related to the observed differences in milk production between Holstein and Montbéliarde, which are two breeds with different mammogenic potential. Some of the 17 miRNAs could potentially target mRNAs involved in signaling pathways (such as mTOR) and in lipid metabolism, thereby suggesting that they could influence milk composition. In conclusion, we showed differences in mammary gland miRNomes of two dairy bovine breeds. These differences suggest a potential role of miRNAs in mammary gland plasticity and in milk component synthesis related to milk production and composition.
Project description:Differential expression analysis of miRNAs in goat (Capra hircus) mammary gland between peak and late lactation by Solexa sequencing