Long non-coding RNA (lncRNA) is a transcription product of the mammalian genome that regulates the development and growth in the body. The present study aimed to analyze the expression dynamics of lncRNA in sika antler mesenchymal and cartilage tissues by high-throughput sequencing. Bioinformatics was applied to predict differentially expressed lncRNAs and target genes and screen lncRNAs and mRNAs related to osteogenic differentiation, cell proliferation, and migration. Finally, the expression of the lncRNAs and target genes were analyzed by qRT-PCR. The results showed that compared to the cartilage tissue, the transcription levels of lncRNA and mRNA, 1212 lncRNAs and 518 mRNAs, in mesenchymal tissue were altered significantly. Thus, a complex interaction network was constructed, and the lncRNA-mRNA interaction network correlation related to osteogenic differentiation, cell proliferation, and migration was analyzed. Among these, the 26 lncRNAs and potential target genes were verified by qRT-PCR, and the results of qRT-PCR were consistent with high-throughput sequencing results. These data indicated that lncRNA promotes the differentiation of deer antler mesenchymal tissue into cartilage tissue by regulating the related osteogenic factors, cell proliferation, and migration-related genes and accelerating the process of deer antler regeneration and development.

Transforming growth factor (TGF‐β) plays an important role in the development of deer antlers. The purpose of this study was to investigate the role of long noncoding RNA in the transcriptional regulation of TGF‐β1 and its relationship with the proliferation and differentiation of antler chondrocytes. High‐throughput sequencing was used to screen lncRNAs related to TGF‐β1. Next, the overexpression plasmid and interference sequence of target lncRNA27785.1 were constructed and transfected into chondrocytes. We found that lncRNA27785.1 inhibited the proliferation and migration of chondrocytes and delayed the transition of cells from G1 to S phase. qRT‐PCR and Western blot analysis indicated that the overexpression of lncRNA27785.1 may downregulate mRNA and protein expression of TGF‐BR2, Smad3, pSmad3, and Smad4. Our findings highlight lncRNA27785.1 as an inhibitor of chondrocytes proliferation and differentiation by negatively regulating the TGF‐β/Smad signaling pathway; this implicates an important regulatory role for long noncoding RNA in the regeneration of antler.

The antler is the unique mammalian organ found to be able to regenerate completely and periodically after loss, and the continuous proliferation and differentiation of mesenchymal cells and chondrocytes together complete the regeneration of the antler. Circular non-coding RNAs (circRNAs) are considered to be important non-coding RNAs that regulate body development and growth. However, there are no reports on circRNAs regulating the antler regeneration process. In this study, full-transcriptome high-throughput sequencing was performed on sika deer antler interstitial and cartilage tissues, and the sequencing results were verified and analyzed. The competing endogenous RNA (ceRNA) network related to antler growth and regeneration was further constructed, and the differentially expressed circRNA2829 was screened out from the network to study its effect on chondrocyte proliferation and differentiation. The results indicated that circRNA2829 promoted cell proliferation and increased the level of intracellular ALP. The analysis of RT-qPCR and Western blot demonstrated that the mRNA and protein expression levels of genes involved in differentiation rose. These data revealed that circRNAs play a crucial regulatory role in deer antler regeneration and development. CircRNA2829 might regulate the antler regeneration process through miR-4286-R+1/FOXO4.