AIM

To characterize the N-methyladenosine (mA) modification patterns in long non-coding RNAs (lncRNAs) in sporadic congenital cataract (CC) and age-related cataract (ARC).

METHODS

Anterior capsule of the lens were collected from patients with CC and ARC. Methylated RNA immunoprecipitation with next-generation sequencing and RNA sequencing were performed to identify mA-tagged lncRNAs and lncRNAs expression. Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses and Gene Ontology annotation were used to predict potential functions of the mA-lncRNAs.

RESULTS

Large amount of mA peaks within lncRNA were identified for both CC and ARC, while the level was much higher in ARC (49 870 peaks) than that in CC (18 688 peaks), yet those difference between ARC in younger age group (ARC-1) and ARC in elder age group (ARC-2) was quite slight. A total of 1305 hypermethylated and 1178 hypomethylated lncRNAs, as well as 182 differential expressed lncRNAs were exhibited in ARC compared with CC. On the other hand, 5893 hypermethylated and 5213 hypomethylated lncRNAs, as well as 155 significantly altered lncRNA were identified in ARC-2 compared with ARC-1. Altered lncRNAs in ARC were mainly associated with the organization and biogenesis of intracellular organelles, as well as nucleotide excision repair.

CONCLUSION

Our results for the first time present an overview of the mA methylomes of lncRNA in CC and ARC, providing a solid basis and uncovering a new insight to reveal the potential pathogenic mechanism of CC and ARC.