Q-type C2H2 zinc-finger protein (C2H2-ZFP) transcription factors are associated with many plant growth development and environmental stress responses. To date, there have been few analyses of the Q-type C2H2-ZFP gene family in alfalfa (Medicago sativa subsp. sativa). In this study, we identified 58 Q-type C2H2-ZFPs across the entire alfalfa genome, and the gene structure, motif composition, chromosomal mapping, and cis-regulatory elements were explored, as well as the expression profiles of specific tissues and the response under different abiotic stresses. According to their phylogenetic features, these 58 MsZFPs were divided into 12 subgroups. Synteny analysis showed that duplication events play a vital role in the expansion of the MsZFP gene family. The collinearity results showed that a total of 26 and 42 of the 58 MsZFP genes were homologous with Arabidopsis and M. truncatula, respectively. The expression profiles showed that C2H2-ZFP genes played various roles in different tissues and abiotic stresses. The results of subsequent quantitative real-time polymerase chain reaction (qRT-PCR) showed that the nine selected MsZFP genes were rapidly induced under different abiotic stresses, indicating that C2H2-ZFP genes are closely related to abiotic stress. This study provides results on MsZFP genes, their response to various abiotic stresses, and new information on the C2H2 family in alfalfa.

The common vetch (Vicia sativa L.) seed is an ideal plant-based protein food for humans, but its edible value is mainly limited by the presence of cyanogenic glycosides that hydrolyze to produce toxic hydrogen cyanide (HCN), and the genes that regulate HCN synthesis in common vetch are unknown. In this study, seeds from common vetch at 5, 10, 15, 20, 25, 30, and 35 days after anthesis were sampled, and the seven stages were further divided into five developmental stages, S1, S2, S3, S4, and S5, based on morphological and transcriptome analyses. A total of 16,403 differentially expressed genes were identified in the five developmental stages. The HCN contents of seeds in these five stages were determined by alkaline titration, and weighted gene coexpression network analysis was used to explain the molecular regulatory mechanism of HCN synthesis in common vetch seeds. Eighteen key regulatory genes for HCN synthesis were identified, including the VsGT2, VsGT17 and CYP71A genes, as well as the VsGT1 gene family. VsGT1, VsGT2, VsGT17 and CYP71A jointly promoted HCN synthesis, from 5 to 25 days after anthesis, with VsGT1-1, VsGT1-4, VsGT1-11 and VsGT1-14 playing major roles. The HCN synthesis was mainly regulated by VsGT1, from 25 to 35 days after anthesis. As the expression level of VsGT1 decreased, the HCN content no longer increased. In-depth elucidation of seed HCN synthesis lays the foundations for breeding common vetch with low HCN content.

The GRAS gene family encodes a group of plant-specific transcription factors essential for regulating plant growth, development and stress responses. While the GRAS gene family has been extensively studied in various plant species, a comprehensive characterization of the GRAS gene family in Medicago ruthenica has not yet been conducted. In this study, a total of 62 MrGRAS gene family members were identified through a comprehensive whole-genome analysis of M. ruthenica, and phylogenetic analysis categorized these 62 genes into 13 distinct groups. Gene structure and conserved domain analysis showed that MrGRAS genes from the same evolutionary branch share similar exon–intron architecture and conserved motifs. A large number of hormone-responsive, growth and development and stress-responsive cis-regulatory elements were detected in the upstream sequences of MrGRAS genes. RT-qPCR analysis showed that drought stress significantly induced the expression of nine selected MrGRAS genes. Overall, this study analyzed the phylogenetic relationships, conserved domains, cis-regulatory elements and expression patterns of the GRAS gene family in M. ruthenica, filling the gap in the identification of the MrGRAS gene family and laying the foundation for functional analysis of the MrGRAS gene family.