Identification, characterization, and evolutionary analysis of aldehyde dehydrogenase (ALDH) genes superfamily in Medicago truncatula L.

Aldehydes are reactive compounds that play crucial roles in various metabolic processes within plants. However, their accumulation can lead to toxic effects, Aldehyde dehydrogenases (ALDHs) represent a diverse family of enzymes that catalyze the oxidation of aldehydes to carboxylic acids. ALDHs help mitigate the toxic effects of these compounds and maintain cellular homeostasis in plants. In this study, a bioinformatics analysis of the Medicago truncatula genome identified 27 MtALDHs, which were classified into ten distinct groups based on their phylogenetic relationships. The distribution of these families across the chromosomes of M. truncatula is uneven, with segmental duplications being the primary factor contributing to the expansion of this gene family within the species. The gene structure and motif analysis within each ALDH family in M. truncatula, along with its orthologous genes in Arabidopsis, exhibits a high degree of conservation. The promoter region analysis of these genes reveals a rich abundance of cis-regulatory elements that respond to various environmental stresses and hormones. Furthermore, examination of the expression patterns of MtALDH genes using available microarray data indicated that several of these genes exhibit high expression levels throughout all developmental stages in M. truncatula. Additionally, some genes display tissue-specific expression and are induced in response to salt stress, suggesting a significant role for these genes in growth processes and stress responses within M. truncatula. The findings from this study provide essential insights and data necessary for the functional evaluation of each MtALDH gene during developmental stages and in response to environmental stresses.