# Genome-wide identification of ethylene receptor protein-coding gene families in wheat and their regulated expression during development and under multiple abiotic stresses

## TL;DR

This study identifies and characterizes ethylene receptor genes in wheat, revealing their roles in development and response to environmental stresses.

## Contribution

The first genome-wide identification and characterization of ethylene receptor genes in hexaploid wheat and its progenitors.

## Key findings

- Eighteen homoeologues of six TaETR genes were identified in hexaploid wheat.
- TaETR genes show tissue-specific expression and differential responses to abiotic stresses.
- Promoter analysis revealed cis-regulatory elements linked to hormone and stress responses.

## Abstract

Ethylene regulates many plant growth and developmental processes and mediates plant-environment interactions. Ethylene signal in plants is perceived by transmembrane ethylene receptor proteins (ETRs), which initiate a cascade downstream signaling events that regulate the expression of ethylene responsive genes. However, the identity and roles of ETRs in wheat remain to be investigated. This study performed genome-wide identification and characterization of ETR genes in hexaploid wheat (Triticum aestivum L.) and its tetraploid and diploid progenitors.

A total of 18 homoeologues of six TaETR genes were identified in the genome of hexaploid wheat, namely TaERS1, TaERS2, TaETR2, TaETR3, TaETR4 and TaETR5, which are distributed unevenly over 4 chromosomes in each of the three subgenomes. These genes typically consist of 1 to 7 exons and 0 to 6 introns, and the exons/introns number in TaETR homoeologues varies with their subgenome origin. The TaETR proteins consist of a minimum of 5 and a maximum of 7 domains, of which cGMP phosphodiesterases/adenylyl cyclases/FhlA (GAF) is a conserved domain. Analysis of the promoter sequences of TaETR genes revealed the presence of eight groups of cis-regulatory elements, which includes hormone and stress responsive elements. Using publicly available transcriptomic data and qRT-PCR, we found that TaETR genes exhibit tissue and stage specific expression patterns during wheat development and differential response to multiple abiotic stresses. The study also characterized ETR genes from the tetraploid and diploid progenitors of hexaploid wheat, T. turgidum ssp. dicoccoides and Aegilops tauschii, respectively.

Ethylene is an important regulator of crop traits of agronomic and economic importance. This study identified ETR genes of wheat and predicted their potential roles during wheat growth and development as well as its interaction with the surrounding environment.

The online version contains supplementary material available at 10.1186/s12870-026-08177-7.