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
Clock genes, such as cryptochrome 1 (CRY1), exhibit rhythmic expression in the reproductive organs. This gene is a key component of the circadian clock and is involved in various physiological processes, including reproduction, suggesting that it may be linked to ovarian activity via neuroendocrine pathways. However, the association between CRY1 variants and ovarian traits in dairy cows is unclear. In this study we used qRT-PCR to assay the mRNA expression of this gene, and found that CRY1 expression was highest in oocytes in several tissues; subsequently, we found that CRY1 expression was highest in the ovary in Chinese Holstein dairy cattle, followed by muscle and spleen tissues (p < 0.01). Next, we identified a six bp insertion/deletion (indel) locus within the CRY1 gene in Chinese Holstein dairy cattle. Only two genotypes were detected: II (n = 854, 83.7%) and ID (n = 166, 16.3%). Association analysis revealed that the identified indel was significantly associated with dominant follicle and corpus albicans diameters (p < 0.05) during metestrus. Specifically, individuals with the ID genotype exhibited smaller dominant follicles and corpus albicans than those with the II genotype. Our preliminary findings suggest that CRY1 is associated with specific ovarian morphological traits and may serve as a basis for further investigation of its potential role in bovine reproductive function.
Xuanbo Chen, Enhui Jiang, Yuta Yang et al.· Biomolecules· 0 citations