# Genome-Wide Identification and Evolutionary Analysis of m6A-Related Gene Family in Poplar Nanlin895

## TL;DR

This study identifies and analyzes m6A-related genes in a poplar species, revealing their evolutionary patterns and roles in stress responses.

## Contribution

The first comprehensive identification and evolutionary analysis of m6A-related genes in Populus deltoides × P. euramericana (NL895).

## Key findings

- 39 m6A-related genes were identified, including 8 writers, 13 erasers, and 18 readers.
- Gene expansion in writers and readers is linked to whole-genome duplication events.
- Promoter analysis shows enrichment of cis-acting elements related to stress and hormone responses.

## Abstract

Background: N6-methyladenosine (m6A) is the most prevalent chemical modification of eukaryotic RNA, playing a crucial role in regulating plant growth and development, stress responses, and other essential biological processes. The enzymes involved in m6A modification—methyltransferases (writers), demethylases (erasers), and recognition proteins (readers)—have been identified in various plant species; however, their roles in the economically significant tree species Populus deltoides × P. euramericana (NL895) remain underexplored. Results: In this study, we identified 39 m6A-related genes in the NL895 genome, comprising 8 writers, 13 erasers, and 18 readers. Evolutionary analysis indicated that the expansion of writers and readers primarily resulted from whole-genome duplication events. Purifying selection pressures were observed on all duplicated gene pairs, suggesting their essential roles in functional differentiation. Phylogenetic analysis revealed that writers, erasers, and readers are categorized into six, four, and two groups, respectively, with these genes being more conserved among dicotyledonous plants. Gene structure, protein domains, and motifs exhibited greater conservation within the same group. Promoter analysis of m6A-related genes showed enrichment of cis-acting elements associated with responses to light, phytohormones, and stress, indicating their potential involvement in gene expression regulation. Under cadmium treatment, the expression of all writers was significantly upregulated in both the aboveground and root tissues of NL895. Conclusions: This study systematically identified m6A-related gene families in Populus deltoides × P. euramericana (NL895), elucidating their evolutionary patterns and expression regulation characteristics. These findings provide a theoretical foundation for analyzing the molecular mechanisms of m6A modification in poplar growth, development, and stress adaptation, and offered candidate genes for molecular breeding in forest trees.