PUBLICATION

PCB126 exposure revealed alterations in m6A RNA modifications in transcripts associated with AHR activation

Authors
Aluru, N., Karchner, S.I.
ID
ZDB-PUB-201020-39
Date
2020
Source
Toxicological sciences : an official journal of the Society of Toxicology   179(1): 84-94 (Journal)
Registered Authors
Karchner, Sibel
Keywords
dioxin-like PCBs, MeRIP, development, epitranscriptomics, m6A, zebrafish
Datasets
GEO:GSE153436
MeSH Terms
  • Animals
  • Methylation
  • Polychlorinated Biphenyls*/toxicity
  • RNA/metabolism
  • Transcriptome
  • Zebrafish/genetics
  • Zebrafish/metabolism
PubMed
33064826 Full text @ Toxicol. Sci.
CTD
33064826
Abstract
Chemical modifications of proteins, DNA and RNA moieties play critical roles in regulating gene expression. Emerging evidence suggests the RNA modifications (epitranscriptomics) have substantive roles in basic biological processes. One of the most common modifications in mRNA and noncoding RNAs is N6-methyladenosine (m6A). In a subset of mRNAs, m6A sites are preferentially enriched near stop codons, in 3' UTRs, and within exons, suggesting an important role in the regulation of mRNA processing and function including alternative splicing and gene expression. Very little is known about the effect of environmental chemical exposure on m6A modifications. As many of the commonly occurring environmental contaminants alter gene expression profiles and have detrimental effects on physiological processes, it is important to understand the effects of exposure on this important layer of gene regulation. Hence, the objective of this study was to characterize the acute effects of developmental exposure to PCB126, an environmentally relevant dioxin-like PCB, on m6A methylation patterns. We exposed zebrafish embryos to PCB126 for 6 hours starting from 72 hours post-fertilization and profiled m6A RNA using methylated RNA immunoprecipitation followed by sequencing (MeRIP-seq). Our analysis revealed 117 and 217 m6A peaks in the DMSO and PCB126 samples (FDR 5%), respectively. The majority of the peaks were preferentially located around the 3'UTR and stop codons. Statistical analysis revealed 15 m6A marked transcripts to be differentially methylated by PCB126 exposure. These include transcripts that are known to be activated by AHR agonists (e.g., ahrra, tiparp, nfe2l2b) as well as others that are important for normal development (vgf, cebpd, sned1). These results suggest that environmental chemicals such as dioxin-like PCBs could affect developmental gene expression patterns by altering m6A levels. Further studies are necessary to understand the functional consequences of exposure-associated alterations in m6A levels.
Genes / Markers
Figures
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Antibodies
Orthology
Engineered Foreign Genes
Mapping