[Screening of the lncRNA SNHG3 regulating expression in the bovine hypothalamus].

This study aimed to screen for the long non-coding RNA (lncRNA) small nucleolar RNA host gene 3 (SNHG3) capable of regulating the expression of cocaine- and amphetamine-regulated transcriptional peptide (CART) in the bovine hypothalamus and elucidate the underlying mechanism. StarBase v2.0, NCBI, and DIANA tools were used to predict the lncRNAs targeting -381 and -491, which were responsible for inhibiting expression. The binding sites were analyzed, and the endogenous expression of the selected lncRNAs was determined by semi-quantitative RT-PCR of the hypothalamus tissue from three healthy adult Simmental cows. The dual-luciferase reporter gene assay was employed to detect the targeted binding relationship between -381/491 and lncRNAs. The over-expression vectors of lncRNAs, , and -381/491 mimics were constructed and transfected into 293T cells to reveal the mechanism of lncRNAs in regulating the expression. Animal experiments were conducted to analyze the regulatory function of the strongest lncRNA at the cellular level. The results showed that lncRNAs TUG1, SNHG3, H19, SNHG12, and DANCR were expressed in the bovine hypothalamus. The lncRNAs TUG1 and SNHG3 had binding sites for -381, and H19, SNHG12, and DANCR had binding sites for -491. The dual-luciferase reporter gene assay showed that -381 inhibited the relative luciferase activities of TUG1-WT ( < 0.05) and SNHG3-WT ( < 0.01), and -491 inhibited the luciferase activities of DANCR-WT ( < 0.05), H19-WT ( < 0.05), and SNHG12-WT ( < 0.01). SNHG3 and SNHG12 up-regulated the expression by specifically binding to -381 ( < 0.001) and -491 ( < 0.01), respectively, and SNHG3 had the strongest effect of regulating expression. The results from animal experiments showed that SNHG3 significantly up-regulated the mRNA and protein levels of CART by specifically binding to -381. This study confirmed that the lncRNA SNHG3, acting as a competing endogenous RNA of -381, significantly up-regulated expression at the transcriptional and post-transcriptional levels, laying a foundation for deciphering the mechanism of the molecular network regulation of CART in the bovine hypothalamus.