Transcriptome-wide map of m(6)A circRNAs identified in a rat model of hypoxia mediated pulmonary hypertension

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.