Genome-Wide Identification, Expression and Evolution Analysis of m6A Writers, Readers and Erasers in Aegilops_tauschii

Abstract

N6-methyladenosine modifications (m6A) is one of the most abundant and prevalent post-transcriptional RNA modifications in plants, playing the crucial role in plant growth and development and stress adaptation. However, the m6A regulatory machinery in Aegilops_tauschii, the D genome progenitor of common wheat, is not well understood at present. Here, we systematically identified the m6A-related genes in Aegilops with a genome-wide search approach. In total, 25 putative m6A genes composed of 5 writers, 13 readers and 7 erasers were obtained. A phylogenetic analysis clearly grouped them into three subfamilies with the same subfamily showing similar gene structures and conserved domains. These m6A genes were found to contain a large number of cis-acting elements associating with plant hormones, regulation of growth and development as well as stress response, suggesting their widespread regulation function. Furthermore, the expression profiling of them was investigated using RNA-seq data to obtain stress-responsive candidates, of which 5 were further validated with a qPCR analysis. Finally, the genetic variation of m6A-related genes was investigated between Aegilops and D subgenome of wheat based on re-sequencing data, and an obvious genetic bottleneck occurred on them during the wheat domestication process. The promising haplotype association with domestication and agronomic traits was also detected. This study provided some insights on the genomic organization and evolutionary features of m6A-related genes in Aegilops, which will facilitate the further functional study and also contribute to broaden the genetic basis for genetic improvement in wheat and other crops.

Transcriptome-Wide N6-Methyladenosine (m6A) Methylation Analyses in a Compatible Wheat–Puccinia striiformis f. sp. tritici Interaction

“…In eukaryotic mRNA, m 6 A is the most abundant methylation type which is also found in bacteria and RNA viruses [3]. The m 6 A RNA modification is a preserved regulatory system across highly diverse organisms; the system encompasses the methyltransferase complexes known as "writers" that add methyl groups to mRNA, demethylases termed "erasers" that remove these modifications for dynamic regulation, and m 6 A-binding proteins or "readers" which recognize and interact with methylated RNA sites, collectively playing a crucial role in mRNA function by impacting processes such as stability, splicing, localization, and translation, thereby illustrating the evolutionary significance of m 6 A modifications [4,5]. There are several m 6 A methyltransferases, called m 6 A writers, including mRNA adenosine methylases (MTA and MTB), VIRILIZER (VIR), FK506-binding protein 12 (FKBP12)-interacting protein 37 (FIB37), and the E3 ubiquitin ligase HAKAI [6].…”