# Genome Identification, Expression Profile Analysis, and Abiotic Stress Response Mechanism of Longan BES1 Gene

## TL;DR

This study identifies and analyzes BES1 genes in longan, revealing their roles in growth, development, and stress responses.

## Contribution

The study provides the first comprehensive analysis of BES1 genes in longan, including their genomic structure and expression patterns.

## Key findings

- Eight BES1 genes were identified and classified into four subgroups with conserved motifs and structures.
- Promoter analysis showed hormone-related elements, suggesting roles in stress responses and hormonal signaling.
- Differential expression was observed in roots, seeds, and under temperature and IAA treatments.

## Abstract

BES1 (BRI1 EMS SUPPRESSOR 1) is a critical transcription factor involved in plant growth, development, and stress responses. Although BES1 genes have been characterized in several species, their roles in longan (Dimocarpus longan Lour.) remain unclear. This study identified and analyzed eight BES1 genes in the longan genome. Phylogenetic analysis classified these genes into four subgroups (I-IV), with conserved motifs and intron–exon structures indicating potential functional similarities within subgroups. Cis-element analysis revealed that the promoters of DlBES1 genes contain numerous hormone-related elements, including ABRE, TGACG, and TCA motifs, suggesting their involvement in hormonal signaling and stress responses. Expression profiling showed differential expression patterns of DlBES1 genes across nine tissues, with notable up-regulation in roots and seeds. Additionally, DlBES1 genes exhibited distinct expression trends under varying temperatures and in response to IAA treatment, indicating potential roles in temperature stress adaptation and hormone signaling. These findings provide novel insights into the regulatory mechanisms of BES1 genes in longan and highlight their potential significance in stress tolerance and growth regulation.