Abstract
BACKGROUND: Shaanbei white cashmere goat is an excellent cashmere goat breed, and its market favored cashmere from the secondary hair follicles. Hair follicles mature around birth and each hair follicle repeatedly undergoes a growth cycle that comprises three distinct stages: anagen, catagen and telogen. Understanding the molecular mechanisms controlling cyclic hair follicle changes is essential for optimizing hair follicle function and improving cashmere production. METHODS: The circRNA expression profile in the hair follicle cycle was constructed and differentially expressed circRNAs were identified, with particular focus on circ 0020938, which was highly expressed during anagen. The functional assays were performed to assess the effect of circ 0020938 on hair follicle stem cells (HFSCs) proliferation. Competing endogenous RNA (ceRNA) network was constructed to investigate the interaction between circ 0020938, miR-142-5p, and DSG4. Rescue experiment was conducted to validate the impact of circ 0020938 on HFSCs proliferation and DSG4 expression. RESULTS: We found that circ 0020938 inhibited HFSCs proliferation. Further analysis revealed that circ 0020938 acted as a sponge for miR-142-5p, alleviating the repression of DSG4. Additionally, we confirmed that DSG4 inhibited HFSCs proliferation, suggesting that it play a key role in regulating the balance between proliferation and differentiation during the hair follicle cycle. Rescue experiments showed that the inhibition of HFSCs proliferation by circ 0020938 was partially reversed by miR-142-5p. CONCLUSION: Our study provides novel insights into the regulatory role of circRNA in HFSCs proliferation during the hair follicle cycle. The results demonstrate that circ 0020938 acts as a miRNA sponge and inhibits HFSCs proliferation through the miR-142-5p/DSG4 axis, thereby contributing to the proper progression of the hair follicle cycle.