Musk Secretion In Muskrats (Ondatra Zibethicus L.): Association With Lipid And Cholesterol Metabolism-Related Pathways

Male muskrats (Ondatra zibethicus L.) secrete musk from their scent glands during musk secretion season. Musk plays an important role as a communication pheromone during the breeding season. In this study, gas chromatography-mass spectrometry (GC-MS) was used to analyze the main components of musk. The GC-MS results after methyl esterification showed that 71.55% of the musk is composed of fatty acids. The other components of muskrat musk include cholesterol (9.31%) and other organics. Transcriptome comparison between musk secretion and non-secretion seasons showed significant changes in the scent glands for 53 genes involved in fatty acid and cholesterol synthesis and metabolism regulatory pathways, which include fatty acid biosynthesis, elongation, and metabolism; steroid biosynthesis; steroid hormone biosynthesis pathways. A reverse transcription-polymerase chain reaction analysis confirmed these detected changes. Overall, our results indicated that lipid synthesis and metabolism play important roles in musk compound synthesis by providing energy for musk production, and the produced musk provides a mechanism for male muskrats to communicate with females during the breeding season.