Comprehensive analysis of differences of N-methyladenosine of lncRNAs between atrazine-induced and normal Xenopus laevis testis.

Background: Increasing evidence suggested N-methyladenosine (mA) modification is crucial for male germline development. However, mA modification of lncRNAs gains a little attention in amphibians in recent years. Xenopus laevis (X. laevis) was chosen to be an ideal model organism for testing environmental endocrine disrupting chemicals (EDCs) exposure and resultant effects. Atrazine (AZ) as an endocrine disrupt can effect development of testis in amphibians. Our previous study revealed that mA is a highly conserved modification across the species.

Results: The results of mA sequences showed that mA-methylated lncRNAs enriched in intergenic region in testes of X. laevis. We further examined the differential expression of lncRNAs mA sites in testes of AZ-exposed and compared with that in animals from control group. The results indicated that up to 198 differentially methylated mA sites were detected within 188 lncRNAs, in which 89 significantly up-methylated sites and 109 significantly down-methylated sites. Data from KEGG pathway analysis indicated that AZ-affected lncRNAs mA sites were mainly involved in 10 pathways in which 3 mutual pathways were found in the result of differentially mA-methylated mRNAs.

Conclusions: These findings suggested that differentially mA-methylated lncRNAs and these 3 pathways may act on regulatory roles in abnormal testis development of AZ-exposed X. laevis. This study for the first time provides insights into the profile of lncRNAs mA modifications in amphibian species.