Basic Pentacysteine (BPC) represents a class of plant-exclusive transcription factors, serving pivotal roles in orchestrating developmental processes and mediating responses to both biotic and abiotic stressors. However, the genome-wide characteristics and low-temperature response mechanism of the BPC gene family in cotton remain unclear. Employing a genome-wide screening approach, this study characterized 60 distinct BPC transcription factor genes across ten Gossypium species. Conserved structural analysis showed that all BPC members carried a highly conserved GAGA-binding domain. Concurrently, the exploration of cis-acting elements within promoter regions demonstrated the potential involvement of these BPC transcription factors in modulating developmental processes, hormone signaling cascades, and abiotic stress adaptation mechanisms. Genomic collinearity analysis shows that segmental duplication is the core mechanism for the expansion of this gene family. Expression analysis indicated that the transcription level of GhBPC4 was significantly increased under low-temperature stress. Genetic function studies displayed that VIGS-mediated GhBPC4 silencing reduced cotton cold tolerance. This study systematically analyzed the genomic characteristics of the cotton BPC transcription factor family and functionally validated the molecular mechanism of GhBPC4-mediated cryogenic response. These findings establish an important foundation for subsequent analysis of multidimensional regulatory networks and the breeding of cold-resistant cotton germplasms.

This research centers on the sand-fixing plant known as Stipagrostis pennata, from which the β-glucosidase gene SpBGLU25 was successfully cloned using the molecular cloning method. SpBGLU25 encodes a hydrophilic and stable protein made up of 193 amino acids, located in the cell membrane. qRT-PCR analysis indicated that the expression of the SpBGLU25 is closely linked to the drought stress tolerance of S. pennata. Following this, functional validation was performed using an Arabidopsis overexpression system. The overexpression of transgenic Arabidopsis lines showed significantly improved drought tolerance under PEG and mannitol treatments. Assessments of germination, root length, and physiological indicators such as proline, malondialdehyde content, soluble sugars, and relative leaf water content (RLWC) further confirmed the enhanced performance of the overexpressing plants. Additionally, the comparative transcriptomic analysis of SpBGLU25-OE Arabidopsis compared to the wild-type (WT) showed that differentially upregulated genes were primarily enriched in categories of “cellular process,” “cell,” and “catalytic activity.” KEGG pathway enrichment analysis indicated that the genes were mainly concentrated in the pathways of phenylpropanoid biosynthesis and plant hormone signal transduction. These findings provide a crucial foundation for further investigation into the function of the SpBGLU25 and its role in regulating plant tissue development and adaptation to stress. This research is anticipated to offer new theoretical insights and genetic resources for enhancing plant stress tolerance through genetic engineering.

Background: The TGACG-BINDING FACTORS (TGA) gene family, a key subgroup of bZIP transcription factors, mediates plant stress responses and developmental processes by binding to the as-1 cis-element in target gene promoters to regulate transcriptional activation or repression. Despite its functional significance, systematic characterization of TGA genes in cotton (Gossypium spp.) remains insufficient. Methods: In this study, we performed a comprehensive genome-wide identification and phylogenetic analysis of TGA members across 10 Gossypium species and verified the functions of candidate genes using VIGS technology. Results: A total of 74 TGA homologous genes with conserved DOG1 and bZIP domains were identified. Evolutionary analysis revealed that the cotton TGA gene family can be classified into five distinct branches, suggesting functional diversification. Functional prediction analyses indicated these genes in cotton growth regulation and stress adaptation, potentially through hormone-mediated signaling pathways. Expression profiling demonstrated both tissue-specific expression patterns and salt-stress responsiveness in Gossypium hirsutum TGA genes, and GhTGA2 exhibited the most significant up-regulated expression under salt stress. Virus-induced gene silencing (VIGS)-mediated GhTGA2 silencing significantly reduced the salt tolerance in cotton. Conclusions: The TGA gene family is involved in regulating cotton growth, development, and stress responses, and plays a critical role in mediating salt stress tolerance in cotton. Our results provide mechanistic insights into cotton stress adaptation and establish a valuable genetic resource for developing elite salt-tolerant cotton cultivars, with direct implications for sustainable cotton production.

The SNAC (Stress-responsive NAC) subfamily, a key branch of the conserved NAC transcription factor family, plays a central role in regulating plant stress response. However, systematic characterization of the SNAC family in cotton (Gossypium spp.) remains unclear. Employing a genome-wide screening approach, this study characterized 75 distinct SNAC transcription factor genes across ten Gossypium species, with tetraploid cottons harboring twice as many as their diploid progenitors. Phylogenetic analysis categorized the genes into three subgroups, with members of the same subgroup exhibiting conserved motif compositions and gene structures. Chromosomal localization revealed a conserved distribution pattern of SNAC genes between the Dt and At subgenomes in tetraploid cotton. Genomic collinearity analysis suggested that the primary driver of SNAC family expansion was segmental duplication. Promoter analysis predicted 2974 cis-regulatory elements, including cold- and hormone-responsive motifs, indicating their potential involvement in stress regulation. These GhSNAC genes indicated significant induced expressions under stress conditions, and GhSNAC3D exhibited the most significant up-regulated expression under low temperature stress. Genetic function studies displayed that VIGS-mediated GhSNAC3D-silencing significantly reduced the cold tolerance in cotton. This study systematically analyzed the genomic characteristics of the cotton SNAC family and functionally validated the molecular mechanism of GhSNAC3D-mediated cryogenic response, which lays a foundation for subsequent research on cold resistance in cotton and stress-resistant breeding.

Background/Objectives: The TOPLESS (TPL) and TOPLESS-related (TPR) proteins represent a highly conserved class of transcriptional co-repressors in plants, playing pivotal roles in modulating growth, development, and stress responses through the repression of key transcriptional regulators. However, a comprehensive genome-wide analysis of the TPL/TPR gene family and its involvement in stress responses remains unexplored in cotton. Methods: In this study, 60 TPL/TPR genes were identified from the genomes of ten Gossypium species via bioinformatics approaches, and their protein physicochemical properties, gene structures, phylogenetic relationships, cis-regulatory elements, and expression profiles were characterized. Results: Chromosomal localization and collinearity analyses revealed that segmental duplication events have contributed to the expansion of the TPL/TPR gene family. Further examination of exon–intron architectures and conserved motifs highlighted strong evolutionary conservation within each TPL/TPR subgroup. Expression profiling demonstrated that TPL/TPR genes exhibit tissue-specific expression patterns, with particularly high transcript abundance in floral organs (e.g., petals and stigmas). Cis-element analysis suggested their potential involvement in multiple stress-responsive pathways. Notably, GhTPL3 showed high constitutive expression across various tissues and under stress conditions, with the most pronounced up-regulation under salt stress. Functional validation via Virus-Induced Gene Silencing (VIGS) confirmed that GhTPL3 silencing significantly impairs cotton salt stress tolerance, underscoring its critical role in abiotic stress adaptation. Conclusions: Our findings provide novel insights into the functional diversification and regulatory mechanisms of the TPL/TPR family in cotton, offering a valuable genetic resource for breeding stress-resilient cotton varieties.