MSTRG3207 promotes apoptosis in zebrafish ZF4 cells via sponging dre-miR-736/bbc3/LOC101885512 axis during cold acclimation.

• The expression of MSTRG3207 is upregulated during cold acclimation in zebrafish ZF4 cells and negatively associated with dre-miR-736. • MSTRG3207 promotes apoptosis by targeting dre-miR-736. • Dre-miR-736 inhibits apoptosis during cold acclimation by downregulating apoptosis-related genes bbc3 and LOC101885512. Long non-coding RNAs (lncRNAs) play essential roles in a variety of biological processes. It has been recently reported that lncRNAs can regulate mRNA expression by binding to microRNAs (miRNAs) as competing endogenous RNAs (ceRNAs). However, the involvement of this regulatory mechanism during cold acclimation in fish remains unclear. In this study, we constructed a ceRNA network mediated by lncRNAs in cold-acclimated zebrafish ZF4 cells through bioinformatic analysis of the mRNA, miRNA, and lncRNA profiles obtained from ZF4 cells cultured at 18 °C for 30 days. A previously uncharacterized lncRNA, MSTRG3207, was selected for further analysis. MSTRG3207 was upregulated and dre-miR-736 was downregulated during cold acclimation. MSTRG3207 was cloned by rapid amplification of cDNA ends (RACE) and functionally characterized. The binding of MSTRG3207 to dre-miR-736 was validated by dual-luciferase reporter assay. Under cold acclimation, MSTRG3207 promoted apoptosis by sponging dre-miR-736 and upregulating bbc3 and LOC101885512, two apoptotic genes targeted by dre-miR-736. Taken together, our findings indicate that MSTRG3207 upregulation promotes apoptosis by sponging dre-miR-736 during cold acclimation in fish. [ABSTRACT FROM AUTHOR]