Comprehensive Analysis of the Transcriptome-Wide m6A Methylome in Pterygium by MeRIP Sequencing

Abstract

AimPterygium is a common ocular surface disease, which is affected by a variety of factors. Invasion of the cornea can cause severe vision loss. N6-methyladenosine (m6A) is a common post-transcriptional modification of eukaryotic mRNA, which can regulate mRNA splicing, stability, nuclear transport, and translation. To our best knowledge, there is no current research on the mechanism of m6A in pterygium.MethodsWe obtained 24 pterygium tissues and 24 conjunctival tissues from each of 24 pterygium patients recruited from Shanghai Yangpu Hospital, and the level of m6A modification was detected using an m6A RNA Methylation Quantification Kit. Expression and location of METTL3, a key m6A methyltransferase, were identified by immunostaining. Then we used m6A-modified RNA immunoprecipitation sequencing (MeRIP-seq), RNA sequencing (RNA-seq), and bioinformatics analyses to compare the differential expression of m6A methylation in pterygium and normal conjunctival tissue.ResultsWe identified 2,949 dysregulated m6A peaks in pterygium tissue, of which 2,145 were significantly upregulated and 804 were significantly downregulated. The altered m6A peak of genes were found to play a key role in the Hippo signaling pathway and endocytosis. Joint analyses of MeRIP-seq and RNA-seq data identified 72 hypermethylated m6A peaks and 15 hypomethylated m6A peaks in mRNA. After analyzing the differentially methylated m6A peaks and synchronously differentially expressed genes, we searched the Gene Expression Omnibus database and identified five genes related to the development of pterygium (DSP, MXRA5, ARHGAP35, TMEM43, and OLFML2A).ConclusionOur research shows that m6A modification plays an important role in the development of pterygium and can be used as a potential new target for the treatment of pterygium in the future.

The mRNA m6A reader YTHDF2 suppresses the proliferation and migration of pterygium fibroblasts

“…Our results showed an increased expression of m6A in pterygium, contrary to the other published report 25 . Under normal circumstances, YTHDF2 is an m6A reader, which could recognize and attaches to the m6A modi ed site and degrades mRNA, reducing m6A levels 20,26 .…”

Atypical U3 snoRNA Suppresses the Process of Pterygium Through Modulating 18S Ribosomal RNA Synthesis

“…The criteria for grading the severity of pterygium were as described in previous studies. 25 Pterygium tissues and a small piece of normal conjunctiva tissue from an autograft at the contralateral corneal limbus were surgically obtained from one patient. Patients with other ocular diseases and/or those who underwent ophthalmic surgery were excluded from the study.…”

Recent progress in N6-methyladenosine modification in ocular surface diseases

“…In histopathology, pterygium specimens are classified by squamous metaplasia of the conjunctival epithelium, goblet cell hyperplasia, disruption of Bowman's layer, and degeneration of subconjunctival collagen and elastin fibers [55] . Jiang et al [56] explored the potential relationship between m6A modifications and pterygium-related genes. Based on a comprehensive data and bioinformatical analysis of the m6Amodified RNA sequence, pterygium and normal conjunctiva were compared for differences in expression of m6A methylation.…”