Project description:This SuperSeries is composed of the following subset Series:; GSE15019: Transcriptome analysis of bovine mammary gland tissue treated with E. coli for 6 hours; GSE15020: Transcriptome analysis of bovine mammary gland tissue treated with E. coli for 24 hours; GSE15022: Transcriptome analysis of bovine mammary gland tissue of an udder quarter adjacent to an E.coli treated one for 24 hrs Experiment Overall Design: Refer to individual Series
Project description:MicroRNAs (miRNAs) are small noncoding RNAs that participate in regulation of gene expression. Their role during mammary gland development is still largely unknown. In the present study, we performed a microarray analysis to identify miRNAs associated with high mammogenic potential of bovine mammary gland. We identified 54 miRNAs differing significantly between mammary tissue of dairy (Holstein-Friesian, HF) and beef (Limousine, LM) post-pubertal heifers. Fifty two miRNAs had higher expression in the mammary tissue of LM heifers. Enrichment analyses for targeted genes revealed that the major differences between miRNA expression in the mammary gland of HF vs. LM were associated with regulation of signalling pathways crucial for mammary gland development, such as: TGF-beta, insulin, WNT and inflammatory pathways. Moreover, a number of genes potentially targeted by differentially expressed miRNAs was associated with mammary stem cells’ activity. These data indicate that in dairy cattle high developmental potential of the mammary gland, leading to high milk productivity, not only depends on central neuro-endocrine regulation but also on specific miRNA expression pattern.
