Identifying long non-coding RNAs and characterizing their functional roles in swine mammary gland from colostrogenesis to lactogenesis

The landscape of long noncoding RNA expression in the goat brain

The brain regulates multiple metabolic processes, such as food intake, energy expenditure, insulin secretion, hepatic glucose production, and glucose and fatty acid metabolism in adipose tissue, which are fundamental for the maintenance of energy and glucose homeostasis during lactation and pregnancy. In addition, brain expression has a fundamental impact on the development of maternal behavior. Although brain functions are partly regulated by long noncoding RNAs (lncRNAs), their expression profiles have not been characterized in depth in any ruminant species. We have sequenced the transcriptome of 12 brain tissues from 3 goats that were 1 mo pregnant and 4 nonpregnant goats to investigate their lncRNA expression patterns. Between 4,363 (adenohypophysis) and 4,604 (olfactory bulb) lncRNAs were expressed in brain tissues, leading us to establish a set of 794 already annotated lncRNAs and 5,098 novel lncRNA candidates. The detected lncRNAs shared features with those of other mammals, and tissue-specific lncRNAs were enriched in brain development-related terms. Differential expression analyses between goats that were 1 mo pregnant and nonpregnant goats showed that the lncRNA expression profiles of certain brain regions experience substantial changes associated with early pregnancy (238 lncRNAs are differentially expressed in the olfactory bulb), but others do not. Enrichment analysis showed that differentially expressed lncRNAs from the olfactory bulb are co-expressed with genes previously linked to behavioral changes related to pregnancy. These findings provide a first characterization of the landscape of lncRNA expression in the goat brain and provides valuable clues to understand the molecular events triggered by early pregnancy in the central nervous system.

Karrow N, Mao Y. Identification and Classification of Long Non-Coding RNAs in the Mammary Gland of the Holstein Cow

The mammary glands, responsible for milk secretion, are regulated at a local level by various hormones, growth factors, non-coding RNAs, and other elements. Recent research has discovered the presence of lncRNAs in these glands, with suggestions that they may be essential for the maintenance and function of mammary glands. Besides directly controlling the gene and protein expression, lncRNAs are believed to play a significant part in numerous physiological and pathological processes. This study focused on examining the mammary gland tissues of Chinese Holstein cows, to identify and categorize long non-coding RNAs (lncRNAs). The research intended to distinguish lncRNAs in the mammary tissues of Holstein cows and contrast them between lactation and non-lactation periods. In this study, mammary gland tissues were sampled from three Holstein cows in early lactation (n = 3, 30 days postpartum) and non-lactation (n = 3, 315 days postpartum) on a large dairy farm in Jiangsu province. Mammary tissue samples were collected during early lactation and again during non-lactation. In total, we detected 1905 lncRNAs, with 57.3% being 500 bp and 612 intronic lncRNAs. The exon count for lncRNAs varied from 2 to 10. It was observed that 96 lncRNA expressions markedly differed between the two stages, with 83 genes being upregulated and 53 downregulated. Enrichment analysis results revealed that Gene Ontology (GO) analysis was primarily abundant in cellular processes. The Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis indicated that target genes were predominantly abundant in metabolic pathways, fatty acid biosynthesis, the immune system, and glycosphingolipid biosynthesis. This study analyzed the expression profile and characteristics of lncRNAs in the mammary gland tissues of Holstein cows during both lactation and non-lactation stages, forming a foundation for further investigation into the functional roles of lncRNAs in Holstein cows throughout lactation.