The aim of this study was to explore the impact of molecular networks constructed by DE-circRNAs related to milk fat synthesis on milk fat synthesis in dairy cows through in-depth analysis. In this study, we used the circRNA library and transcriptome sequencing data of Holstein dairy cows with high and low milk fat percentage constructed previously to screen and identify DE-circ RNAs(circPRKAA2) related to milk fat synthesis, and further predicted their ceRNA regulatory network using Targetscan and miRanda software. Real-time fluorescence quantitative PCR, RNA pull down assay and dual luciferase reporter assay were used to verify the targeting relationship. Oil red O and BODIPY staining were used to investigate the effect of target miRNA on lipid droplet secretion in BMECs. The results indicated that the regulatory relationship of the ceRNA (circPRKAA2/miR-22-3p/SLC27A1) network was successfully predicted and verified, and 9 miRNAs and 10 candidate mRNAs were predicted, and it was clarified that circPRKAA2 and miR-22-3p were mainly distributed in the cytoplasm of BMECs. circPRKAA2 negatively regulated miR-22-3p during the process of milk fat synthesis in BMECs. miR-22-3p inhibited the secretion of lipid droplets, the production of triglycerides and cholesterol in BMECs, and negatively regulated SLC27A1. In conclusion, this study analyzed and verified the targeting relationship of circPRKAA2/miR-22-3p/SLC27A1 and its regulatory effect on milk fat synthesis, with the hope of providing new insights for improving milk quality.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |