Plant specialized metabolites sit at the boundary between plant genetics, environmental response, and useful natural products. Their accumulation is rarely constitutive; instead, it changes with tissue type, developmental stage, stress exposure, hormone signaling, and cellular storage capacity. In this review, we revisit basic helix-loop-helix (bHLH) transcription factors as regulatory switch points in plant specialized metabolism, with particular attention to the jasmonate-JAZ-MYC module. In resting tissues, JAZ repressors dampen MYC/bHLH activity. After wounding, herbivory, pathogen challenge, or elicitation, jasmonoyl-isoleucine promotes COI1-dependent JAZ turnover, freeing MYC factors to bind E-box/G-box motifs, recruit co-regulators such as MED25, and activate biosynthetic genes or downstream transcription-factor cascades. This logic has been repeatedly adapted in different plant lineages to regulate terpenoids, alkaloids, phenylpropanoids, flavonoids, glucosinolates, phytoalexins, and related metabolites. Examples discussed include Arabidopsis sesquiterpenes and glucosinolates, Taxus taxanes, Artemisia artemisinin, Catharanthus terpenoid indole alkaloids, Salvia phenolic acids and tanshinones, Ginkgo terpene trilactones, rice diterpenoid phytoalexins, and cotton gossypol. Rather than treating bHLHs as stand-alone master regulators, we frame them as context-dependent nodes whose outputs depend on dimer choice, promoter grammar, chromatin accessibility, hormone crosstalk, partner transcription factors, and cell-type competence. We also outline evidence standards and engineering principles for using bHLH switches in crop defense, food-quality improvement, medicinal-plant production, and synthetic biology.

High-accuracy NIRS models and GWAS identified a novel QTL qPO-A07-1. GhMYB86 was validated to enhance seed protein content and fiber strength, and a functional KASP marker was developed. Cottonseed is rich in protein and oil; improving its nutritional quality is vital for global food security. In this study, near-infrared spectroscopy (NIRS) models were developed for predicting cottonseed protein and oil content using least absolute shrinkage and selection operator (LASSO) regression, achieving validation R2 of 0.969 (P < 0.01) and 0.972 (P < 0.01), respectively. Using these models, 249 upland cotton (Gossypium hirsutum L) accessions were phenotyped across five environments and subjected to a genome-wide association study (GWAS) based on a 10-K liquid-phase single-nucleotide polymorphism (SNP) array, resulting in the identification of 24 significant loci (P < 1 × 10−4). A novel stable quantitative trait locus (QTL), qPO-A07-1, was detected, within which GhMYB86 was prioritized as a candidate gene. This gene exhibited higher expression in high-protein-content varieties during ovule development. Heterologous overexpression in Arabidopsis thaliana increased seed protein content by 2.61–3.34

Plant specialized metabolites connect genetic programs and environmental responses with ecologically and economically valuable natural products. Their accumulation is rarely constitutive, varying instead with tissue identity, developmental stage, stress exposure, hormone signaling, and cellular storage capacity. This review examines basic helix-loop-helix (bHLH) transcription factors as regulatory switch points in plant specialized metabolism, with emphasis on the jasmonate-JAZ-MYC module. In resting tissues, JAZ repressors constrain MYC/bHLH activity; after wounding, herbivory, pathogen challenge, or elicitation, jasmonoyl-isoleucine triggers COI1-dependent JAZ turnover, releasing MYC factors to bind E-box/G-box motifs, recruit coregulators such as MED25, and activate biosynthetic genes or downstream transcription-factor cascades. Plant lineages have repeatedly adapted this regulatory logic to control terpenoids, alkaloids, phenylpropanoids, flavonoids, glucosinolates, phytoalexins, and related metabolites. Comparative examples include Arabidopsis sesquiterpenes and glucosinolates, Taxus taxanes, Artemisia artemisinin, Catharanthus terpenoid indole alkaloids, Salvia phenolic acids and tanshinones, Ginkgo terpene trilactones, rice diterpenoid phytoalexins, and cotton gossypol. Across these systems, bHLH output depends on dimer choice, promoter grammar, chromatin accessibility, hormone crosstalk, partner transcription factors, and cell-type competence. Six shared principles emerge: signal gating, topology matched to pathway architecture, partner-dependent promoter decoding, spatial competence, feedback rheostats, and evidence-dependent transferability. We further discuss evidence standards, multi-omics-guided factor discovery, miRNA-mediated post-transcriptional control, and engineering strategies for crop defense, food quality, medicinal-metabolite production, and synthetic biology. Unlike pathway- or MYC2-centered surveys, this review organizes the literature within a direct–cascade–hybrid framework that integrates promoter grammar, spatial competence, storage anatomy, and an explicit evidence hierarchy.

Abstract Background An endophytic fungal strain (Penicillium simplicissimum CEF-818) with excellent biocontrol potential was isolated from cotton plants in our previous study, but its mechanism of suppressing cotton Verticillium wilt (caused by Verticillium dahliae) remains unclear. This study aimed to clarify the biocontrol efficacy of CEF-818 and the underlying mechanism. Results CEF-818 showed strong inhibitory activity against V. dahliae. A bioactive compound was isolated and identified as 5-hydroxymethyl-2-furancarboxylic acid (HFA) via spectroscopic and chromatographic analyses. In vitro biological activity assays indicated that HFA inhibited V. dahliae mycelial growth with a median effective concentration (EC₅₀) of 25.29 µg·mL⁻1. Microscopic observations revealed that HFA disrupted the fungal cell membrane integrity, damaged intracellular organelles (e.g., mitochondria and nuclei), and further inhibited spore germination and microsclerotia formation—two critical processes in V. dahliae's disease cycle. Transcriptome sequencing and bioinformatics analysis showed that HFA targets membrane-intrinsic components (e.g., membrane transporters and lipid biosynthesis-related proteins) and perturbs key metabolic pathways (e.g., ribosomal biogenesis and valine metabolism), thereby impairing fungal cell viability and pathogenicity. Conclusion This study confirms that HFA effectively inhibits the growth and pathogenicity of V. dahliae. Mechanistically, HFA disrupts the structural integrity of V. dahliae's cell membrane and induces reactive oxygen species (ROS) accumulation, leading to severe cellular damage and fungal death. These findings provide a scientific basis for developing HFA as a novel bioactive agrochemical fungicide for the sustainable control of cotton Verticillium wilt.

Thaumatin-like proteins (TLPs), a subclass of pathogenesis-related proteins (PR5) distinguished by the unique and stable “TLP-fold” structure, are ubiquitously found across plants, animals, and fungi. TLPs play a pivotal role as effector molecules in plant antimicrobial defense, while their structural flexibility and involvement in complex regulatory networks allow them to integrate multiple phytohormone signals, including salicylic acid, jasmonic acid, ethylene, and abscisic acid. This enables a coordinated response to both biotic and abiotic stresses, positioning TLPs as an “integrative hub” in plant stress adaptation. This review synthesizes the current literature on gene functional validation, providing a systematic overview of the structural characteristics, evolutionary features, and regulatory mechanisms of the TLP family. It emphasizes the multifunctionality and molecular mechanisms of TLPs in disease resistance, stress tolerance, growth regulation, and their role as allergens. Additionally, it discusses the central role of TLPs in integrating stress responses and their potential applications in crop resistance breeding, offering valuable insights for future research.

Seed vigor is an important trait ecologically, agronomically, and economically, and is controlled by manifold genetic and exogenous factors. Dehydration-responsive element-binding protein 2B (DREB2B), a subgroup of the DREB transcription factor family, is well-known for conferring multiple abiotic stress resistance. However, the role of DREB2B in seed vigor has not been identified. Here, DREB2B was identified as a negative regulator of seed vigor using a loss-of-function mutant, gene editing, and over-expressing transgenic lines studies in Arabidopsis and Gossypium spp. The lower and higher sensitivity of loss-of-function mutants and overexpression lines of DREB2B to abscisic acid (ABA) and fluridone, respectively, emphasized the negative roles of DREB2B in seed vigor and germination via the ABA-mediated pathway. Further genetic and molecular analyses revealed that DREB2B exhibits both synergistic and independent functions in regulating seed germination and vigor concerning ABA INSENSITIVE 3 (ABI3). We observed that DREB2B formed transcriptional complexes with Radical-Induced Cell Death1 (RCD1) and Similar to RCD One 1 (SRO1) to regulate seed germination and vigor. In addition, RNA-seq analysis of dreb2b and rcd1-3 lines indicated that DREB2B and RCD1 may target the same pathways in seed germination and vigor associated with ABA accumulation modification, which is supported by DREB2B directly regulating ABA DEFICIENT 2 (ABA2) promoter activity. Collectively, these results suggest that ABA-mediated complexes consisting of DREB2B, RCD1, SRO1, and ABI3 function upstream of ABA2 to negatively regulate seed vigor in plants, expanding on our knowledge of seed development.

DNA methylation consists of 5-methylcytosine and N6-methyl deoxyadenosine (6mA) and is crucial in plant development. However, its specific role and potential mechanism to initiate cotton fibers remain unclear. This study employed Oxford Nanopore Technologies (ONT) sequencing to analyze DNA methylation alterations in ZM24 and ZM24 fuzzless-lintless (ZM24fl) during fiber initiation. Our results indicated that DNA 6mA methylation exhibited the most remarkable difference among ovule samples at -2, 0, and 5 d post anthesis of ZM24 and ZM24fl. Subsequently, genes with significant changes in DNA 6mA methylation and transcription during fiber initiation were screened. We found that GhMAF1 displayed significant transcriptional upregulation and 6mA enrichment in its promoter, which could serve as a potential target for DNA 6mA in fiber initiation. Further, we knocked out GhMAF1 using CRISPR-Cas technology and demonstrated that GhMAF1 specifically promotes the initiation of fiber cells at the base of the ovule by mediating the downstream JAZ2/CPC-MML3/MML4 pathway. These findings unveil a novel spatial module of fiber cell initiation on the ovule surface that involves GhMAF1. Ultimately, this work provides significant knowledge for the regulatory network of DNA 6mA modification in fiber initiation to improve fiber yield and quality.

Cotton is a commercially valuable fiber crop, renowned for its unique fiber properties. The distinctive features of cotton fiber result from complex interactions among various genetic and molecular pathways. One intriguing aspect of cotton fiber is its natural color, which offers the potential to develop a diverse spectrum of naturally colored cotton fibers. This review aims to elucidate these complexities by examining the inheritance patterns of different fiber colors. Initially, it was proposed that distinct genes were responsible for the color traits of cotton fiber, such as green, brown, and white, based on Mendelian inheritance patterns. Traditionally, a dominant brown fiber gene was believed to be the primary determinant of brown fiber color. However, recent advancements in cotton genetics have identified numerous genes involved in pigment production, regulatory components influencing fiber color, and genetic variants contributing to the diverse range of fiber colors. Key metabolic pathways have been mapped, revealing genes encoding the corresponding enzymes, such as chalcone synthase (GhCHS), which is linked to the flavonoid production pathway and associated with brown and green fiber coloration. Proanthocyanidins and their derivatives, produced via the flavonoid pathway, are the primary pigments in brown fiber. The expression of flavonoid pathway genes is regulated by a major locus Lc1 linked to the MYB transcription factor gene TRANSPARENT TESTA 2 (GhTT2). Brown and green fiber colors are partially dominant traits controlled by single genes, suggesting that gene expression dosage impacts the phenotype of colored cotton. The review highlights the crucial role of genetic and epigenetic processes in determining fiber color. Additionally, it nuanced interaction between dominant brown and white fiber genes and the involvement of multiple loci or modifier genes influencing color intensity.

Hydrogen peroxide (H2O2) displays significant and dual effects on seed germination and seedling development, depending on the application dosage. However, the definition of H2O2 thresholds and the mechanisms underlying the dual actions in Arabidopsis seed germination and seedling development are not yet clear. Here, we analyzed the Arabidopsis seed germination profiles in response to different concentrations of exogenous H2O2 and found that 2 mM functions as the key threshold, above this threshold, both seed germination and seedling establishment were gradually inhibited. By RNA-seq analysis and function verification, we identified pathways of abscisic acid (ABA) signalling, seed post-ripening, energy metabolism, ROS homeostasis, and cell wall loosening play positive roles in seed germination and seedling establishment downstream of the H2O2 signalling. Further physio-chemical approaches revealed that exogenous H2O2 affected the accumulation and distribution of O2 center dot- and H2O2 in embryonic tissues by regulating the tissue-specific expression of SDH2-3, RHD2, and PRXs. Collectively, we found that germination rate and aerial growth were positively correlated with endogenous H2O2 content and root length was positively correlated with O2 center dot- accumulation, demonstrating that different ROS signals played specific functions in different tissues and development processes. On the other hand, excessive H2O2 (10 mM) represses these two processes for radicle cell damage caused by oxidation stress. Finally, we put forward the mechanism model of the dual effects of exogenous H2O2 on seed germination and seedling establishment.

Cottonseeds, rich in high-quality protein and fatty acids, represent a vital plant-derived feedstuff and edible oil resource. To systematically investigate genetic variation patterns in nutritional quality and screen superior germplasm, this study analyzed 26 nutritional quality traits and 8 fiber traits across 259 upland cotton (Gossypium hirsutum L.) accessions using multivariate statistical approaches. Results revealed significant genetic diversity in cottonseed nutritional profiles, with coefficients of variation ranging from 3.42% to 26.37%. Moreover, with advancements in breeding periods, the contents of protein, amino acids, and the proportion of unsaturated fatty acids (UFAs) increased, while oil content and C16:0 levels decreased. Correlation analyses identified significant positive associations (p < 0.05) between proteins, amino acids, UFAs, and most fiber traits, except for seed index (SI), fiber micronaire (FM), and fiber elongation (FE). Through a principal component analysis–fuzzy membership function (PCA-FMF) model, 13 elite accessions (F > 0.75) with high protein content, high UFA proportion, and excellent fiber quality were identified. These findings provide both data-driven foundations and practical germplasm resources for value-added utilization of cottonseed and coordinated breeding for dual-quality traits of nutrition and fiber.

Introduction:Verticillium wilt is a severe soil-borne disease that affects cotton growth and yield. Traditional monitoring methods, which rely on manual investigation, are inefficient and impractical for large-scale applications. This study introduces a novel approach combining machine learning with feature selection to identify sensitive spectral features for accurate and efficient detection of cotton Verticillium wilt. Methods:We conducted comprehensive hyperspectral measurements using handheld devices (350-2500 nm) to analyze cotton leaves in a controlled greenhouse environment and employed Unmanned Aerial Vehicle (UAV) hyperspectral imaging (400-995 nm) to capture canopy-level data in field conditions. The hyperspectral data were pre-processed to extract wavelet coefficients and spectral indices (SIs), enabling the derivation of disease-specific spectral features (DSSFs) through advanced feature selection techniques. Using these DSSFs, we developed detection models to assess both the incidence and severity of leaf damage by Verticillium wilt at the leaf scale and the incidence at the canopy scale. Initial analysis identified critical spectral reflectance bands, wavelet coefficients, and SIs that exhibited dynamic responses as the disease progressed. Results:Model validation demonstrated that the incidence detection models at the leaf scale achieved a peak classification accuracy of 85.83%, which is about 10% higher than traditional methods without feature selection. The severity detection models showed improved precision as disease severity of damage increased, with accuracy ranging from 46.82% to 93.10%. At the canopy scale, UAV-based hyperspectral data achieved a remarkable classification accuracy of 93.0% for disease incidence detection. Discussion:This study highlights the significant impact of feature selection on enhancing the performance of hyperspectral-based remote sensing models for cotton wilt monitoring. It also explores the transferability of sensitive spectral features across different scales, laying the groundwork for future large-scale early warning systems and monitoring cotton Verticillium wilt.

The protein and oil content in cottonseed, known for their high quality, exhibits substantial variation across different cotton varieties. This study explored the regulatory mechanisms behind these differences by analyzing protein and oil accumulation patterns, transcriptomics, and metabolomics in two cotton varieties during seed development. Results showed that protein and oil rapidly accumulated between 15 and 30 days post-anthesis (DPA), but significant differences between varieties emerged after 40 DPA. Differentially expressed genes (DEGs) at 40 DPA were enriched in carbon allocation, fatty acid degradation, and nitrogen absorption pathways. Metabolomics identified lipids, lipid-like molecules, and organic acids as key differentially accumulated metabolites (DAMs). Furthermore, the gene GhNIR1, associated with nitrogen source absorption, was identified. Virus-induced gene silencing (VIGS) of this gene in cotton resulted in a significant reduction in protein content in the roots, stems, and leaves. These findings provide insights into protein and oil accumulation and offer genetic resources for improving cottonseed nutritional quality.

Salt stress poses a major restricting factor for sustainable agricultural development, limiting crop productivity and adversely affecting crop productivity. Grafting is a commonly used technique to improve the quality and stress resilience of horticultural crops. However, limited research has utilized grafting to explore the role of key mobile mRNAs in response to salt stress for molecular breeding applications. In this study, grafting systems were established between cotton and okra or tobacco. Through these systems, the 60S Ribosomal Protein L19-2 (RL192) mRNA was identified as a mobile molecule moved from cotton (rootstock) to okra (scion). Fluorescence quantification and beta-glucuronidase (GUS) staining analyses showed that GhRL192 expression was significantly induced by salt stress. Silencing GhRL192 in cotton significantly reduced salt stress tolerance, whereas overexpression of GhRL192 in tobacco or Arabidopsis improved seed germination and root development and the survival rate of seedlings under salt stress. This novel grafting strategy between horticultural and agricultural crops provides new insights and methodologies for studying mobile mRNAs that enhance crop stress resistance, yield, and quality. The identification and analysis of GhRL192 mRNA in relation to salt tolerance confirmed the feasibility of this approach, laying the groundwork for further exploration of transport mechanisms and molecular regulatory networks.

Cotton is an important crop for fiber production, but the genetic basis underlying key agronomic traits, such as fiber quality and flowering days, remains complex. While machine learning (ML) has shown great potential in uncovering the genetic architecture of complex traits in other crops, its application in cotton has been limited. Here, we applied five machine learning models-AdaBoost, Gradient Boosting Regressor, LightGBM, Random Forest, and XGBoost-to identify loci associated with fiber quality and flowering days in cotton. We compared two SNP dataset down-sampling methods for model training and found that selecting SNPs with an Fscale value greater than 0 outperformed randomly selected SNPs in terms of model accuracy. We further performed machine learning quantitative trait loci (mlQTLs) analysis for 13 traits related to fiber quality and flowering days. These mlQTLs were then compared to those identified through genome-wide association studies (GWAS), revealing that the machine learning approach not only confirmed known loci but also identified novel QTLs. Additionally, we evaluated the effect of population size on model accuracy and found that larger population sizes resulted in better predictive performance. Finally, we proposed candidate genes for the identified mlQTLs, including two argonaute 5 proteins, Gh_A09G104100 and Gh_A09G104400, for the FL3/FS2 locus, as well as GhFLA17 and Syntaxin-121 (Gh_D09G143700) for the FSD09_2/FED09_2 locus. Our findings demonstrate the efficacy of machine learning in enhancing the identification of genetic loci in cotton, providing valuable insights for improving cotton breeding strategies.

Understanding early embryonic development is fundamental for unraveling plant cell differentiation and organogenesis. Here we integrate multiomics data from 403 upland cotton ovules to identify 2,960 metabolic quantitative trait loci and 24,485 expression quantitative trait loci. A key locus, ME_A07, influencing 252 known metabolite levels and expression of 4,293 genes, with the MYB gene GhTT2_A07 identified as central regulator, potentially regulated by a 520 kb inversion. GhTT2_A07 orchestrated both primary and secondary metabolite biosynthesis, influencing agronomic traits. Another locus, ME_A06, driven by the MYB gene Proanthocyanidin Regulator (GhPAR), modulates proanthocyanin content and suggests an ecological adaptation. GhTT2_A07 and GhPAR exhibit both shared and distinct expression profiles, contributing variably to fiber quality and yield. These findings highlight the critical role of MYB genes in the early development of cotton ovules and fibers, offering comprehensive multiomics resources that advance cotton research and molecular breeding.

The cuticular wax of terrestrial plants' outer epidermis is indispensable in plant reproductive development and response to external environmental stress. Alkanes are the main component of cuticle wax and fatty acid hydroxylases play a key role in alkane biosynthesis; however, their function in cotton remains elusive. Here, 53, 55, 28 and 28 candidate fatty acid hydroxylase superfamily (FAHS) genes in four cultivated cotton species were identified. The FAHSs share relatively conserved gene tructure and motifs. We conducted a systematic structural, expression and functional regulatory analysis of the FAHS genes in cotton. Transcriptome analysis indicated that GhFAHS11 is highly expressed specifically in reproductive organs, especially stamens. Sequence analysis revealed that GhFAHS11 and AtCER1 share conserved histidine-rich domains, LEGW motif and seven transmembrane domains. Yeast two-hybrid analyses showed that GhFAHS11, GhFAR3 and GhCER2 are all subcellularly localized to the endoplasmic reticulum (ER) and interacted with each other. Moreover, GhFAHS11 is co-expressed with CER3 and CYTB5, involved in cuticular wax biosynthesis. When GhFAHS11 transcription was reduced in cotton, anther dehiscence was blocked, pollen grains were depressed, and pollen activity was reduced. These findings indicate that GhFAHS11 affects the biosynthesis of cotton anther cuticular wax, which regulates the development of anther and pollen, ultimately affecting male fertility. This study provides a reference for the biosynthesis of cotton cuticle wax and its effects on reproductive development and environmental stress responses.

The guided entry of TA proteins (GET) pathway, which is responsible for the post-translational targeting and insertion of the tail-anchored (TA) protein into the endoplasmic reticulum (ER), plays an important role in physiological processes such as protein sorting, vesicle trafficking, cell apoptosis, and enzymatic reactions in which the GET1/2 complex is indispensable. However, a comprehensive study of the GET1 and GET2 genes and the GET pathway in cotton has not yet been carried out. Here, 12 GET1 and 21 GET2 genes were identified in nine representative plant species, and the phylogenetic relationships, gene structures, protein motifs, cis-regulatory elements (CREs), and temporal and spatial expression profiles were analyzed thoroughly. Our study indicated that GhGET1s and GhGET2s might be localized on ER membranes. According to expression profiling and CREs analysis, GhGET2-A02 was identified as a promising candidate for fiber cell development, interacting with two GhGET1s in the membrane, with a binding bias toward GhGET1-A06. Silencing of GhGET1-A06 or GhGET2-A02 reduced fiber initiation and elongation. In summary, our research provides important evidence for understanding the gene families and functions of GET1 and GET2 in cotton and provides clues for molecular breeding of high-quality cotton fiber varieties.

The germination process of seeds is influenced by the interplay between two opposing factors, pectin methylesterase (PME) and pectin methylesterase inhibitor (PMEI), which collectively regulate patterns of pectin methylesterification. Despite the recognized importance of pectin methylesterification in seed germination, the specific mechanisms that govern this process remain unclear. In this study, we demonstrated that the overexpression of GhPMEI53 is associated with a decrease in PME activity and an increase in pectin methylesterification. This leads to seed cell wall softening, which positively regulates cotton seed germination. AtPMEI19, the homologue in Arabidopsis thaliana, plays a similar role in seed germination to GhPMEI53, indicating a conserved function and mechanism of PMEI in seed germination regulation. Further studies revealed that GhPMEI53 and AtPMEI19 directly contribute to promoting radicle protrusion and seed germination by inducing cell wall softening and reducing mechanical strength. Additionally, the pathways of abscicic acid (ABA) and gibberellin (GA) in the transgenic materials showed significant changes, suggesting that GhPMEI53/AtPMEI19-mediated pectin methylesterification serves as a regulatory signal for the related phytohormones involved in seed germination. In summary, GhPMEI53 and its homologs alter the mechanical properties of cell walls, which influence the mechanical resistance of the endosperm or testa. Moreover, they impact cellular phytohormone pathways (e.g., ABA and GA) to regulate seed germination. These findings enhance our understanding of pectin methylesterification in cellular morphological dynamics and signaling transduction, and contribute to a more comprehensive understanding of the PME/PMEI gene superfamily in plants.

BACKGROUND:Long-chain acyl-coenzyme A synthetase (LACS) is a type of acylating enzyme with AMP-binding, playing an important role in the growth, development, and stress response processes of plants.RESULTS:The research team identified different numbers of LACS in four cotton species (Gossypium hirsutum, Gossypium barbadense, Gossypium raimondii, and Gossypium arboreum). By analyzing the structure and evolutionary characteristics of the LACS, the GhLACS were divided into six subgroups, and a chromosome distribution map of the family members was drawn, providing a basis for further research classification and positioning. Promoter cis-acting element analysis showed that most GhLACS contain plant hormones (GA, MeJA) or non-biological stress-related cis-elements. The expression patterns of GhLACS under salt stress treatment were analyzed, and the results showed that GhLACS may significantly participate in salt stress response through different mechanisms. The research team selected 12 GhLACSs responsive to salt stress for tissue expression analysis and found that these genes are expressed in different tissues.CONCLUSIONS:There is a certain diversity of LACS among different cotton species. Analysis of promoter cis-acting elements suggests that GhLACS may be involved in regulating plant growth, development and stress response processes. GhLACS25 was selected for in-depth study, which confirmed its significant role in salt stress response through virus-induced gene silencing (VIGS) and induced expression in yeast cells.

BackgroundThe whole life of a plant is regulated by complex environmental or hormonal signaling networks that control genomic stability, environmental signal transduction, and gene expression affecting plant development and viability. Seed germination, responsible for the transformation from seed to seedling, is a key initiation step in plant growth and is controlled by unique physiological and biochemical processes. It is continuously modulated by various factors including epigenetic modifications, hormone transport, ROS signaling, and interaction among them. ROS showed versatile crucial functions in seed germination including various physiological oxidations to nucleic acid, protein, lipid, or chromatin in the cytoplasm, cell wall, and nucleus.Aimof review: This review intends to provide novel insights into underlying mechanisms of seed germination especially associated with the ROS, and considers how these versatile regulatory mechanisms can be developed as useful tools for crop improvement.Key scientific concepts of reviewWe have summarized the generation and elimination of ROS during seed germination, with a specific focus on uncovering and understanding the mechanisms of seed germination at the level of phytohormones, ROS, and epigenetic switches, as well as the close connections between them. The findings exhibit that ROS plays multiple roles in regulating the ethylene, ABA, and GA homeostasis as well as the Ca2+ signaling, NO signaling, and MAPK cascade in seed germination via either the signal trigger or the oxidative modifier agent. Further, ROS shows the potential in the nuclear genome remodeling and some epigenetic modifiers function, although the detailed mechanisms are unclear in seed germination. We propose that ROS functions as a hub in the complex network regulating seed germination.