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

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 m6A-modified. The abundance of circRNAs was influenced by m6A. Furthermore, the significance of m6A circRNAs has not been elucidated in HPH yet. Here we aim to investigate the transcriptome-wide map of m6A circRNAs in HPH. Differentially expressed m6A abundance was detected in lungs of HPH rats. M6A abundance in circRNAs was significantly reduced in hypoxia in vitro. M6A circRNAs were mainly from protein-coding genes spanned single exons in control and HPH groups. Moreover, m6A influenced the circRNA-miRNA-mRNA co-expression network in hypoxia. M6A circXpo6 and m6A circTmtc3 were firstly identified to be downregulated in HPH. Our study firstly identified the transcriptome-wide map of m6A circRNAs in HPH. M6A can influence circRNA-miRNA-mRNA network. Furthermore, we firstly identified two HPH-associated m6A circRNAs: circXpo6 and circTmtc3. However, the clinical significance of m6A circRNAs for HPH should be further validated.