The Role of BMP7 in the Proliferation of Hu Sheep Dermal Papilla Cells Is Influenced by DNA Methylation

Abstract

Simple Summary Dermal papilla cells (DPCs) play a key role in the growth and development of hair follicles, and their number can regulate the shape and size of hair. Previous studies found that the BMP7 gene is differentially expressed in Hu sheep lamb skin of different pattern types and plays a key role in the proliferation of Hu sheep DPCs. However, the molecular mechanism of the differential expression of the BMP7 gene remains unclear. Here, we aim to investigate the cause of the BMP7 gene differentially expressed in Hu sheep lamb skin of different pattern types. Our findings demonstrate that DNA methylation modification can affect the expression of the BMP7 gene and can regulate the proliferation and cell cycle of Hu sheep DPCs. Abstract Previous studies have shown that the BMP7 gene is differentially expressed in Hu sheep lamb skin of different pattern types, and its expression level is significantly correlated with hair follicle indices of different pattern types, but the molecular mechanism of the differential expression of the BMP7 gene remains unclear. This study investigated the effect of DNA methylation on the transcriptional expression of BMP7. Firstly, we found that the mRNA expression of the BMP7 gene and the activity of the core promoter of the BMP7 gene were upregulated after 5-Aza-Deoxycytidine-induced demethylation treatment using qRT-PCR and double luciferase reporter assay. Then, we found that the proliferation of Hu sheep DPCs in vitro was promoted after 5-Aza-Deoxycytidine-induced demethylation treatment through qRT-PCR, CCK-8, and EdU assay, and that the overexpression of DNMT1 in DPCs induced the opposite effect. In addition, the results of the cell cycle assay reveal that the percentage of cells in the S phase was increased after 5-Aza-Deoxycytidine-induced demethylation treatment, and that the percentage of cells in the S phase was decreased after overexpression of DNMT1 in DPCs. This study indicated that the differential expression of the BMP7 gene in different patterns of Hu sheep lamb skin may be regulated by DNA methylation modification. In addition, DNA methylation can regulate the proliferation and cell cycle of DPCs in Hu sheep.