oar-miR-29b: Oar-mir-29b is a microRNA that is involved in the regulation of various biological processes in sheep, including curly fleece growth and testicular development [PMC5948824] [PMC10035661] [PMC8017185]. It has been shown to interact with other microRNAs, such as oar-miR-22-3p, oar-miR-23a, and oar-miR-30a-5p, to regulate SIRT1 and follicular development [PMC5948824]. Oar-mir-29b is downregulated in sheep testes with the progression of age, and its expression negatively correlates with the expression of circ_024949, circ_026259, and IGF1 [PMC8017185]. Circ_026259 has been found to inhibit oar-mir-29b in Sertoli cells and promote the expression of IGF1 [PMC8017185]. In addition to its role in testicular development, oar-mir-29b has also been implicated in modulating the expression of CD80 and CD86 [PMC9428447]. The expression patterns of circ_024949, circ_026259, oar-mir-29b, and IGF1 are similar in various testicular cells including germ cells, Leydig cells, and Sertoli cells [PMC8017185]. The regulatory effect of circ_026259 on IGF1 expression through oar-mir-29b has been confirmed using luciferase reporter assays [PMC8017185]. Overall, this research provides insights into the role of oar-mir-29b in sheep testicular function and its interactions with other molecules involved in this process [PMC8017185].