Small heat shock proteins play a pivotal role in maintaining protein homeostasis under abiotic stress conditions and are indispensable for plant viability. In the present study, a comprehensive characterization of this gene family in Allium sativum was conducted through genome-wide sequence identification, phylogenetic reconstruction, conserved motif analysis, promoter cis-element profiling, transcriptomic investigation, quantitative real-time PCR, subcellular localization, and yeast-based functional assays. A total of 114 small heat shock protein genes were identified across eight chromosomes and subsequently classified into ten phylogenetic subgroups. All encoded proteins conserved the α-crystallin domain, whereas their exon–intron architectures and promoter elements responsive to environmental stress or phytohormones exhibited considerable diversity. The predicted proteins range from 130 to 364 amino acids, with isoelectric points (pI) spanning 3.97 to 9.95 and GRAVY values from −1.131 to −0.014, indicating predominantly hydrophilic characteristics. Subcellular localization analysis revealed a broad distribution across the cytoplasm, chloroplasts, mitochondria, and other compartments, with the majority (74 proteins) localized in the cytoplasm. Synteny analysis uncovered two segmentally duplicated gene pairs (AsHSP20-80/31, and AsHSP20-81/32), both showing strong purifying selection (Ka/Ks = 0.0459 and 0.2545, respectively), suggesting functional conservation. Expression profiling demonstrated predominant transcript accumulation in bulbs and floral organs, with significant induction under heat, salinity, and jasmonic acid treatments. qRT–PCR validation further confirmed that several candidate genes, notably AsHSP20-94 and AsHSP20-79, were strongly and consistently upregulated across multiple stress conditions, underscoring their roles as core stress-responsive regulators. Subcellular localization experiments demonstrated that representative proteins are targeted to the cytoplasm, nucleus and chloroplasts. Furthermore, heterologous expression of AsHSP20-79 in yeast conferred marked thermotolerance. Collectively, these findings reveal extensive expansion and functional divergence of the small heat shock protein gene family in garlic and provide valuable candidate genes for improving stress resilience in this important crop species.

Yam (Dioscorea cayennensis subsp. rotundata,hereafter referred to as Dioscorea rotundata) is a staple tropical tuber crop with notable nutritional and economic value. Its development and yield depend on efficient sucrose allocation from source tissues. Sucrose transporters (SUTs), a conserved family of membrane proteins, mediate sucrose loading, translocation, and unloading. Although well-studied in model plants and cereals, SUTs in yam remain largely uncharacterized. This study aims to identify and characterize the SUT gene family in yam and explore their roles in sucrose transport and tuber development. We conducted a genome-wide analysis of yam SUT genes, including gene structure, subcellular localization, and phylogeny. Molecular docking was used to predict sucrose-binding residues, and qRT-PCR assessed gene expression across tissues and tuber developmental stages. Eight SUT genes were identified and classified based on sequence similarity and domain structure. Docking analysis revealed key residues involved in sucrose binding and possible conformational shifts influencing transport. Expression profiling showed that most SUT genes, especially in the tuber apex, were progressively upregulated during development, suggesting roles in sucrose unloading and cell expansion. Additionally, functional validation of DrSUT1 in Arabidopsis thaliana confirmed its involvement in sucrose transport, supporting its role in yam sucrose partitioning. Yam SUT genes, especially those highly expressed in sink tissues, are involved in sucrose partitioning and tuber development. These findings provide structural and functional insights into SUT-mediated sugar transport and lay a foundation for improving sucrose utilization and yield in yam and other tuber crops.

This study provides the first comprehensive genome-wide identification and characterization of the SWEET gene family in yam (Dioscorea rotundata), integrating structural bioinformatics, gene expression profiling, and functional validation to explore its roles in sucrose transport and tuber development. A total of 19 SWEET genes were identified and predicted to localize to the plasma membrane, and they showed high phylogenetic conservation with Arabidopsis thaliana, suggesting conserved functions in sugar distribution. Yeast substrate assays revealed that DrSWEET6 and DrSWEET12 are capable of transporting both hexose and sucrose across the plasma membrane, with their expression predominantly observed in the tuber, implicating their involvement in sucrose unloading. Expression profiling indicated high expression levels of the SWEET genes at the tuber apex, which progressively increased during tuber development, underscoring their critical roles in sucrose unloading, cell expansion, and biomass accumulation. These findings provide novel insights into the structural and functional mechanisms of the SWEET-mediated sucrose transport in yam, laying a solid foundation for future crop improvement strategies aiming to optimize sucrose distribution and enhance tuber yield and quality.

Jasmonate ZIM-domain (JAZ) proteins are pivotal repressors in the jasmonate (JA) signaling pathway, yet their specific roles in garlic (Allium sativum) remain largely unexplored. In this study, 28 AsJAZ genes were identified through a genome-wide analysis. The expansion of this family was primarily driven by whole-genome duplication events, with a significant majority (71.43%) of members belonging to a lineage-specific clade, Subfamily E. While AsJAZ proteins harbor conserved TIFY and Jas domains, they exhibit diverse gene structures and subcellular localization patterns. Notably, AsJAZ17 is strictly localized to the nucleus, whereas AsJAZ16 shows a nucleocytoplasmic distribution, suggesting potential functional compartmentalization within the family. Transcriptomic and qRT–PCR analyses revealed that most AsJAZ genes are responsive to heat, salt, and methyl jasmonate (MeJA) treatments. Protein–protein interaction (PPI) modeling and yeast two-hybrid (Y2H) assays confirmed that AsJAZ17 physically interacts with the MYC2 transcription factor, identifying it as a key regulator within the conserved COI1-JAZ-MYC2 signaling module. Functional validation demonstrated that overexpression of AsJAZ17 in Arabidopsis significantly enhances salt tolerance. This improvement is attributed to an optimized growth-defense trade-off and a reinforced antioxidant defense system, as evidenced by the increased activities of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT), which collectively maintain reactive oxygen species (ROS) homeostasis under stress. These findings provide comprehensive insights into the evolutionary and functional landscape of the garlic JAZ family and identify AsJAZ17 as a promising candidate gene for molecular breeding to improve abiotic stress resilience in Allium crops.