CircCOPS8 Inhibits the Proliferation of Buffalo Myoblasts by Binding to IGF2BP3 and Promoting ATR Gene Expression

Buffaloes are vital livestock in South-East Asia, attributed to their adaptation to hot and humid climates as well as their capacity to produce high-quality milk and meat. However, the texture of buffalo meat is suboptimal and its slow growth rate restricts the development of the buffalo farming industry. Consequently, studies exploring the key biochemical factors associated with buffalo muscle development have become a research focus. CircRNAs are a class of non-coding RNAs which can function as molecular sponges, participate in protein scaffold formation, and encode short peptides. Previous studies have shown that circRNAs are capable of regulating muscle development; however, relatively few reports have addressed their association with buffalo muscle development. In this study, data from Western blotting and RT-qPCR showed that circCOPS8 significantly enhanced the differentiation of buffalo myoblasts while inhibiting their proliferation (p < 0.05). In contrast, in a mouse model of muscular injury, circCOPS8 prevented the repair of injured muscles. Additionally, RIP-qPCR assays confirmed that circCOPS8 could bind to IGF2BP3 (p < 0.05). Furthermore RT-qPCR and transcriptome sequencing results revealed that circCOPS8 inhibited cell growth by upregulating the expression of genes such as ATR (p < 0.05). Our findings suggested that circCOPS8 promoted the differentiation and apoptosis of buffalo myoblasts while inhibiting their proliferation. The inhibition of cell proliferation was primarily mediated by the binding of circCOPS8 to IGF2BP3 and the promotion of ATR gene expression. This study investigated the role and underlying mechanism of circCOPS8 in buffalo myoblasts, which will extend our understanding of non-coding RNA-mediated regulation of buffalo muscle development, with the ultimate goal of improving the meat quality of buffaloes.