# Genome-Wide Characterization and Analysis of the FH Gene Family in Medicago truncatula Under Abiotic Stresses

## TL;DR

This study explores the FH gene family in Medicago truncatula and how it responds to environmental stresses like cold, drought, and salt.

## Contribution

The study identifies 18 FH genes in Medicago truncatula and reveals their roles in stress response and cytoskeleton regulation.

## Key findings

- MtFH genes show significant transcriptional responsiveness to cold, drought, and salt stress.
- MtFH genes are regulated by 22 miRNAs at the post-transcriptional level.
- Phylogenetic analysis shows Medicago truncatula and soybean have closer relationships in FH gene evolution.

## Abstract

Background: The formin family proteins play an important role in guiding the assembly and nucleation of linear actin and can promote the formation of actin filaments independently of the Arp2/3 complex. As a key protein that regulates the cytoskeleton and cell morphological structure, the formin gene family has been widely studied in plants such as Arabidopsis thaliana and rice. Methods: In this study, we conducted comprehensive analyses, including phylogenetic tree construction, conserved motif identification, co-expression network analysis, and transcriptome data mining. Results: A total of 18 MtFH gene family members were identified, and the distribution of these genes on chromosomes was not uniform. The phylogenetic tree divided the FH proteins of the four species into two major subgroups (Clade I and Clade II). Notably, Medicago truncatula and soybean exhibited closer phylogenetic relationships. The analysis of cis-acting elements revealed the potential regulatory role of the MtFH gene in light response, hormone response, and stress response. GO enrichment analysis again demonstrated the importance of FH for reactions such as actin nucleation. Expression profiling revealed that MtFH genes displayed significant transcriptional responsiveness to cold, drought, and salt stress conditions. And there was a temporal complementary relationship between the expression of some genes under stress. The protein interaction network indicated an interaction relationship between MtFH protein and profilin, etc. In addition, 22 miRNAs were screened as potential regulators of the MtFH gene at the post-transcriptional level. Conclusions: In general, this study provides a basis for deepening the understanding of the physiological function of the MtFH gene and provides a reference gene for stress resistance breeding in agricultural production.