Genome-Wide Identification of the Trihelix Transcription Factor Family and Functional Analysis of the Drought Stress-Responsive Genes in Melilotus albus

The trihelix gene family is a plant-specific family of transcription factors that play an important role in many metabolic pathways, including plant growth and development and stress responses. Drought stress is a major factor limiting the distribution and yield of Melilotus albus. However, the distribution of this gene family in M. albus and its biological functions in response to drought stress have not been reported. To investigate the responses of functional genes to drought stress in M. albus, in this study, a total of 34 MaGTs were identified and characterized, of which 32 MaGT proteins were predicted to be nuclear-localized. Based on conserved motif and phylogenetic analyses, the MaGTs could be divided into five subgroups (GT-1, GT-2, SH4, GT-gamma, SIP1). Seven potential candidate genes for drought tolerance were screened and identified via qRT-PCR based on a transcriptome data analysis of drought stress in M. albus. The results indicated that MaGT17 was not only significantly upregulated in the roots after 24 h of drought stress, but also showed a significant induction in the shoots. This finding further confirms that MaGT17 is capable of responding to drought stress in M. albus. Taken together, these results will offer essential insights for understanding the underlying molecular mechanisms of the trihelix proteins and useful data for further research on the growth, development and stress responses of trihelix proteins in M. albus.

Automated summary

The trihelix gene family plays a crucial role in metabolic pathways and stress responses in plants. However, little is known about its distribution and functions in Melilotus albus, particularly in response to drought stress. In this study, 34 MaGTs were identified and characterized, and seven potential candidate genes for drought tolerance were identified. A key finding is the significant upregulation of MaGT17 in response to drought stress in both roots and shoots. These findings provide important insights into the molecular mechanisms and responses of trihelix proteins in M. albus.