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[Display omitted] • Milk fat is an important indicator of milk quality. • Milk fat synthesis involves a dynamic and intricate regulatory network comprising a series of genes. • TAG synthesis is based on two mechanisms: de novo synthesis in mammary epithelial cells and absorption from circulating blood. • Noncoding RNA participates in milk fat synthesis. With the rapid development of China's economy and dairy industry, the people's requirement for milk quality is increasing. Milk fat is a crucial indicator of milk quality. Therefore, exploring the regulatory mechanisms of milk fat synthesis is important. Depending on chain length, milk fatty acids are produced through two mechanisms: de novo synthesis in mammary epithelial cells and uptake from circulating blood. Milk fat synthesis involves many enzymes, proteins and regulatory factors and is a complex and dynamic process. In this paper, recent progress in the transcriptional regulation of milk fat synthesis is reviewed with a focus on the de novo synthesis of fatty acids, the uptake and transport of preformed fatty acids, fatty acid desaturation, triglyceride formation and lipid droplet secretion. In particular, the recently discovered regulatory roles of noncoding RNA are emphasized. Our paper will provide a reference for future research on milk fat derived from dairy cows. [ABSTRACT FROM AUTHOR]

Abstract The pituitary gland is a key endocrine organ responsible for growth and development. To get closer to understanding important molecular mechanisms at work in the bovine pituitary and identifying the core genes controlling growth, in the present study we have analyzed the transcriptome profiling of the pituitary glands of two cattle breeds (Wenshan and Simmental cattle) with extreme growth differences using high-throughput RNA sequencing. Our study revealed that the overall gene expression levels are quite similar between the two breeds. A total of 18,065 annotated genes were identified, which accounted for 85% of the annotated genes in cattle. The five most abundant hormone genes (GH , PRL , POMC , CGA , and LHB) were relatively stable in both breeds, indicating their pivotal roles in maintaining the basic functions of the pituitary. In addition, 105 genes were identified as differentially expressed between Wenshan and Simmental pituitary glands, including 83 known and 22 novel genes. Functional association analyses of the differentially expressed genes between the breeds revealed 60 enriched gene ontology terms and 3 Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. Interestingly, the most enriched KEGG pathway, cell adhesion molecules, can modulate pituitary hormone secretion by cell-cell contact. Our findings demonstrated that SYTL2, SLC38A4, and NCAM2 are new candidates for crucial functions in the secretory pathways of the pituitary gland. These results will further understanding of the important molecular mechanisms at work in the bovine pituitary. Highlights • A total of 105 genes were differentially expressed. • SYTL2 and SLC38A4 are new candidates for crucial functions in the secretory pathway. • Cell adhesion molecules are the most significantly enriched Kyoto Encyclopedia of Genes and Genomes pathway. [ABSTRACT FROM AUTHOR]