Alternations of N6-methyladenosine RNA methylation landscape in pulmonary arterial hypertension

Abstract

Abstract Background N6-methyladenosine (m6A) methylation is the most prevalent and abundant RNA modifications in eukaryotes. Deregulation of m6A changes by m6A-specific enzymes can affect the stability and function of transcripts. However, the relevance of m6A mRNA and m6A-specific enzymes in pulmonary arterial hypertension (PAH) have not been extensively explored. Objectives This study aimed to analyze m6A methylation transcriptomic profiling in the pulmonary arteries of PAH rats, and to find potential m6A regulators corelated with PAH epi-transcriptomic changes. Methods MeRIP-seq and RNA-seq were applied to identify differences in m6A methylation and gene expression in pulmonary artery tissues from control and monocrotaline PAH rats. The expression of a m6A regulator in pulmonary arteries was further analyzed by western blot, flow cytometry, immunohistochemical staining and immunofluorescence. The proliferation and apoptosis assays were further performed in primary rat pulmonary artery smooth muscle cells (PASMCs). Results Twenty-seven differentially expressed genes with hypermethylated or hypomethylated m6A modifications were identified. These differentially expressed genes were mainly linked to the extracellular matrix and structure, MAPK and PI3K-Akt signaling pathways. Furthermore, we firstly detected a m6A reader leucine rich pentatricopeptide repeat containing (LRPPRC) with downregulated expression in PAH rats. PASMCs with a siRNA knockdown of the LRPPRC promoted proliferation and apoptotic resistance. Conclusion This study showed that altered m6A transcriptome-wide landscape and relevant regulatory mechanisms of the PAH pulmonary artery tissues in rats, which might provide a new and potential target for therapeutic interventions in PAH.LRPPRC functional studies in PASMCs