Transcriptome-wide map of m6A circRNAs identified in a rat model of hypoxia mediated pulmonary hypertension

Abstract Background: Hypoxia mediated pulmonary hypertension (HPH) is a lethal disease and lacks effective therapy. CircRNAs play significant roles in physiological process. Recently, circRNAs are found to be m 6 A-modified. The abundance of circRNAs was influenced by m 6 A. Furthermore, the significance of m 6 A circRNAs has not been elucidated in HPH yet. Here we aim to investigate the transcriptome-wide map of m 6 A circRNAs in HPH. Results: Differentially expressed m 6 A abundance was detected in lungs of HPH rats. M 6 A abundance in circRNAs was significantly reduced in hypoxia in vitro . M 6 A circRNAs were mainly from protein-coding genes spanned single exons in control and HPH groups. Moreover, m 6 A influenced the circRNA–miRNA–mRNA co-expression network in hypoxia. M 6 A circXpo6 and m 6 A circTmtc3 were firstly identified to be downregulated in HPH. Conclusion: Our study firstly identified the transcriptome-wide map of m 6 A circRNAs in HPH. M 6 A can influence circRNA–miRNA–mRNA network. Furthermore, we firstly identified two HPH-associated m 6 A circRNAs: circXpo6 and circTmtc3. However, the clinical significance of m 6 A circRNAs for HPH should be further validated. Key words: m 6 A circRNAs; hypoxia mediated pulmonary hypertension; m 6 A circXpo6; m 6 A circTmtc3