FTO-dependent m6A modification of Plpp3 in circSCMH1-regulated vascular repair and functional recovery following stroke

Abstract Vascular repair is considered a key restorative measure to improve long-term outcomes after ischemic stroke. N 6 -methyladenosine (m 6 A), the most prevalent internal modification in eukaryotic mRNAs, functionally mediates vascular repair. However, whether circular RNA SCMH1 (circSCMH1) promotes vascular repair by m 6 A methylation after stroke remains to be elucidated. Here, we identify the role of circSCMH1 in promoting vascular repair in peri-infarct cortex of male mice and male monkeys after photothrombotic (PT) stroke, and attenuating the ischemia-induced m 6 A methylation in peri-infarct cortex of male mice after PT stroke. Mechanically, circSCMH1 increased the translocation of ubiquitination-modified fat mass and obesity-associated protein (FTO) into nucleus of endothelial cells (ECs), leading to m 6 A demethylation of phospholipid phosphatase 3 ( Plpp3 ) mRNA and subsequently the increase of Plpp3 expression in ECs. Our data demonstrate that circSCMH1 enhances vascular repair via FTO-regulated m 6 A methylation after stroke, providing insights into the mechanism of circSCMH1 in promoting stroke recovery.