摘要
Genome duplication events,comprising whole-genome duplication and single-gene duplication,produce a complex genomic context leading to multiple levels of genetic changes.However,the characteristics of m^(6)A modification,the most widespread internal eukaryotic mRNA modification,in polyploid species are still poorly understood.This study revealed the characteristics of m^(6)A methylomes within the early formation and following the evolution of allopolyploid Brassica napus.We found a complex relationship between m^(6)A modification abundance and gene expression level depending on the degree of enrichment or presence/absence of m^(6)A modification.Overall,the m^(6)A genes had lower gene expression levels than the non-m^(6)A genes.Allopolyploidization may change the expression divergence of duplicated gene pairs with identical m^(6)A patterns and diverged m^(6)A patterns.Compared with duplicated genes,singletons with a higher evolutionary rate exhibited higher m^(6)A modification.Five kinds of duplicated genes exhibited distinct distributions of m^(6)A modifications in transcripts and gene expression level.In particular,tandem duplication-derived genes showed unique m^(6)A modification enrichment around the transcript start site.Active histone modifications(H3K27ac and H3K4me3)but not DNA methylation were enriched around genes of m^(6)A peaks.These findings provide a new understanding of the features of m 6A modification and gene expression regulation in allopolyploid plants with sophisticated genomic architecture.
基金
This work was supported by the National Natural Science Foundation of China(31970241).
