Alteration of N6 -Methyladenosine mRNA Methylation in a Rat Model of Cerebral Ischemia–Reperfusion Injury

Abstract

AimThis study was conducted in order to reveal the alterations in the N6-methyladenosine (m6A) modification profile of cerebral ischemia–reperfusion injury model rats.Materials and MethodsRats were used to establish the middle cerebral artery occlusion and reperfusion (MCAO/R) model. MeRIP-seq and RNA-seq were performed to identify differences in m6A methylation and gene expression. The expression of m6A methylation regulators was analyzed in three datasets and detected by quantitative real-time polymerase chain reaction, western blot, and immunofluorescence.ResultsWe identified 1,160 differentially expressed genes with hypermethylated or hypomethylated m6A modifications. The differentially expressed genes with hypermethylated m6A modifications were involved in the pathways associated with inflammation, while hypomethylated differentially expressed genes were related to neurons and nerve synapses. Among the m6A regulators, FTO was specifically localized in neurons and significantly downregulated after MCAO/R.ConclusionOur study provided an m6A transcriptome-wide map of the MACO/R rat samples, which might provide new insights into the mechanisms of cerebral ischemia–reperfusion injury.

Characterization of N6-Methyladenosine in Domesticated Yak Testes Before and After Sexual Maturity

“…Next, we determined whether the identified m 6 A peaks shared any common motifs. We found that m 6 A modifications were typically present in 5-RRACH-3 (R = A or G; H = A, C, or U) sequences ( Figure 3D ), as reported previously ( Yi et al, 2021 ).…”

“…Among these, the most common internal modification in higher eukaryotes is m 6 A, which is important for mRNA metabolism and a variety of biological processes (Liu et al, 2018). m 6 A, discovered in the early 1970s, is a reversible and dynamic modification involving the methyltransferase complex (writer), demethylases (erasers), and binding proteins (readers) (Zhao Y. et al, 2021). Methyltransferase complexes, including methyltransferase-like 3 (METTL3), METTL14, and Wilms' tumor 1-associated protein (WTAP) (Lin et al, 2017), induce methylation, which can be reversed by fat mass and obesityassociated factor (FTO) and AlkB homologue 5 (ALKBH5) (Jia et al, 2011;Zheng et al, 2013a).…”

Regulation of N6-methyladenosine (m6A) RNA methylation in microglia-mediated inflammation and ischemic stroke

“…It is observed that m6A modification increases in conditions like oxygen-glucose deprivation/reoxygenation (OGD/R) or middle cerebral artery occlusion and reperfusion (MCAO/R) ( Chokkalla et al, 2019 ). Researchers found that the demethylases (ALKBH5 and FTO) primarily contribute to causing abnormal m6A modification in IS ( Xu et al, 2020a ; Yi et al, 2021 ). Yi et al (2021) conducted a study in cerebral ischemia-reperfusion injury (CIRI) rat model to discover the variations in the m6A modifications and identified 1,160 differentially expressed genes having hypermethylated or hypomethylated m6A modifications.…”

“…Researchers found that the demethylases (ALKBH5 and FTO) primarily contribute to causing abnormal m6A modification in IS ( Xu et al, 2020a ; Yi et al, 2021 ). Yi et al (2021) conducted a study in cerebral ischemia-reperfusion injury (CIRI) rat model to discover the variations in the m6A modifications and identified 1,160 differentially expressed genes having hypermethylated or hypomethylated m6A modifications. The genes that showed differential expression due to hypermethylation were found to participate in inflammation-related processes, while genes with hypomethylation modification were found to be associated with the functioning of neurons and nerve synapses.…”

“…FTO, a demethylase, was explicitly present in neurons. Its downregulation was observed following MCAO/R, which caused elevation in the m6A level ( Yi et al, 2021 ). Similarly, Xu et al (2020a) found that in rat models, m6A levels increased with ALKBH5 expression in the cerebral cortex and primary neurons following MCAO and OGD/R, respectively.…”