Adipose tissue development significantly influences meat quality and economic traits in beef cattle. In this study, we identified a novel circular RNA derived from two exons (exons 3 and exons 9) of the NID2 gene, designated as circNID2, which exhibits high structural stability and marked upregulation during bovine adipocyte differentiation. Functional assays demonstrated that circNID2 suppresses the proliferation and apoptosis of bovine preadipocytes while robustly promoting adipogenic differentiation and lipid accumulation. Although containing several putative open reading frames, circNID2 lacks protein-coding potential. Mechanistically, circNID2 functions as a competing endogenous RNA by sponging miR-339a, thereby relieving the post-transcriptional repression of its downstream target, Neuronatin (NNAT). Functional rescue experiments further validated that circNID2 partially neutralizes the regulatory effects of miR-339a on preadipocyte proliferation, apoptosis, and differentiation. Collectively, these findings demonstrate that circNID2 regulates bovine preadipocyte function through the newly established circNID2/miR-339a/NNAT axis. This study provides novel insights into the post-transcriptional mechanisms governing mammalian adipogenesis and highlights circNID2 as a potential molecular target for improving fat deposition traits in cattle.
Yue Liu, Mengyang Zhang, Zhuoyuan He et al.· Biomolecules· 0 citations
The genetic and physiological variations among individuals of Holstein dairy cattle contribute to variations in milk yield. Selecting high-yield cows is critical for improving lactation performance. The present study aimed to identify functional genetic variants of the 3′ untranslated region (3′ UTR) in the ELF5 gene associated with milk production traits and to elucidate their underlying molecular mechanisms. A total of 1314 Chinese Holstein cows were genotyped, and a novel single nucleotide polymorphism (SNP), ELF5 g.32793 G>T, was identified in the 3′ UTR of ELF5. This SNP was significantly associated with milk production, such as milk yield, milk fat percentage, milk protein percentage, and somatic cell score. Bioinformatic prediction and dual-luciferase reporter assays demonstrated that the ELF5 g.32793 G>T affects the interaction between bta-miR-487a and the ELF5 3′ UTR. Functional analyses in bovine mammary epithelial (MAC-T) cells showed that bta-miR-487a suppressed cell proliferation by inducing G0/G1 phase arrest and reduced the expression of proliferation-related proteins. Collectively, these findings suggested that bta-miR-487a participates in the regulation of MAC-T cell growth and that the ELF5 g.32793 G>T polymorphism may influence lactation performance through an miRNA-associated mechanism. Therefore, the variant can be used as a functional marker for marker-assisted selection in dairy cattle breeding.
Lin Ma, Li Sun, Haotian Zhang et al.· Biomolecules· 0 citations
