Ethylene Signaling Research Articles

Phosphate deficiency increases plant susceptibility to Botrytis cinerea infection by inducing the abscisic acid pathway.

Plants have evolved finely regulated defense systems to counter biotic and abiotic threats. In the natural environment, plants are typically challenged by simultaneous stresses and, amid such conditions, crosstalk between the activated signaling pathways becomes evident, ultimately altering the outcome of the defense response. As an example of combined biotic and abiotic stresses, inorganic phosphate (Pi) deficiency, common in natural and agricultural environments, can occur along with attack by the fungus Botrytis cinerea, a devastating necrotrophic generalist pathogen responsible for massive crop losses. We report that Pi deficiency in Arabidopsis thaliana increases its susceptibility to infection by B. cinerea by influencing the early stages of pathogen infection, namely spore adhesion and germination on the leaf surface. Remarkably, Pi-deficient plants are more susceptible to B. cinerea despite displaying the appropriate activation of the jasmonic acid and ethylene signaling pathways, as well as producing secondary defense metabolites and reactive oxygen species. Conversely, the callose deposition in response to B. cinerea infection is compromised under Pi-deficient conditions. The levels of abscisic acid (ABA) are increased in Pi-deficient plants, and the heightened susceptibility to B. cinerea observed under Pi deficiency can be reverted by blocking ABA biosynthesis. Furthermore, high level of leaf ABA induced by overexpression of NCED6 in Pi-sufficient plants also resulted in greater susceptibility to B. cinerea infection associated with increased spore adhesion and germination, and reduced callose deposition. Our findings reveal a link between the enhanced accumulation of ABA induced by Pi deficiency and an increased sensitivity to B. cinerea infection.

Exploring the Role of Debaryomyces hansenii as Biofertilizer in Iron-Deficient Environments to Enhance Plant Nutrition and Crop Production Sustainability.

The European "Green Deal" policies are shifting toward more sustainable and environmentally conscious agricultural practices, reducing the use of chemical fertilizer and pesticides. This implies exploring alternative strategies. One promising alternative to improve plant nutrition and reinforce plant defenses is the use of beneficial microorganisms in the rhizosphere, such as "Plant-growth-promoting rhizobacteria and fungi". Despite the great abundance of iron (Fe) in the Earth's crust, its poor solubility in calcareous soil makes Fe deficiency a major agricultural issue worldwide. Among plant promoting microorganisms, the yeast Debaryomyces hansenii has been very recently incorporated, for its ability to induce morphological and physiological key responses to Fe deficiency in plants, under hydroponic culture conditions. The present work takes it a step further and explores the potential of D. hansenii to improve plant nutrition and stimulate growth in cucumber plants grown in calcareous soil, where ferric chlorosis is common. Additionally, the study examines D. hansenii's ability to induce systemic resistance (ISR) through a comparative relative expression study by qRT-PCR of ethylene (ET) biosynthesis (ACO1), or ET signaling (EIN2 and EIN3), and salicylic acid (SA) biosynthesis (PAL)-related genes. The results mark a significant milestone since D. hansenii not only enhances nutrient uptake and stimulates plant growth and flower development but could also amplify induced systemic resistance (ISR). Although there is still much work ahead, these findings make D. hansenii a promising candidate to be used for sustainable and environmentally friendly integrated crop management.

Biocontrol agents modulate phyllosphere microbiota interactions against pathogen Pseudomonas syringae

The pathogen Pseudomonas syringae, responsible for a variety of diseases, poses a considerable threat to global crop yields. Emerging biocontrol strategies employ antagonistic microorganisms, utilizing phyllosphere microecology and systemic resistance to combat this disease. However, the interactions between phyllosphere microbial dynamics and the activation of the plant defense system remain poorly understood. Here we show significant alterations in phyllosphere microbiota structure and plant gene expression following the application of biocontrol agents. We reveal enhanced collaboration and integration of Sphingomonas and Methylobacterium within the microbial co-occurrence network. Notably, Sphingomonas inhibits P. syringae by disrupting pathogen chemotaxis and virulence. Additionally, both Sphingomonas and Methylobacterium activate plant defenses by upregulating pathogenesis-related gene expression through abscisic acid, ethylene, jasmonate acid, and salicylic acid signaling pathways. Our results highlighted that biocontrol agents promote plant health, from reconstructing beneficial microbial consortia to enhancing plant immunity. The findings enrich our comprehension of the synergistic interplays between phyllosphere microbiota and plant immunity, offering potential enhancements in biocontrol efficacy for crop protection.

GhWER controls fiber initiation and early elongation by regulating ethylene signaling pathway in cotton (Gossypium hirsutum).

The online version contains supplementary material available at 10.1007/s11032-024-01477-6.

Overexpression of phosphatidylserine synthase IbPSS1 enhances salt tolerance by stimulating ethylene signaling-dependent lignin synthesis in sweetpotato roots

Phosphatidylserine (PS) is an important lipid signaling required for plant growth regulation and salt stress adaptation. However, how PS positively regulate plant salt tolerance is still largely unknown. In this study, IbPSS1-overexpressed sweetpotato plants that exhibited overproduction of PS was employed to explore the mechanisms underlying the PS stimulation of plant salt tolerance. The results revealed that the IbPSS1-overexpressed sweetpotato accumulated less Na+ in the stem and leaf tissues compared with the wild type plants. Proteomic profile of roots showed that lignin synthesis-related proteins over-accumulated in IbPSS1-overexpressed sweetpotato. Correspondingly, the lignin content was enhanced but the influx of Na + into the stele was significantly blocked in IbPSS1-overexpressed sweetpotato. The results further revealed that ethylene synthesis and signaling related genes were upregulated in IbPSS1-overexpressed sweetpotato. Ethylene imaging experiment revealed the enhancement of ethylene mainly localized in the root stele. Inhibition of ethylene synthesis completely reversed the PS-overproduction induced lignin synthesis and Na+ influx pattern in stele tissues. Taken together, our findings demonstrate a mechanism by which PS regulates ethylene signaling and lignin synthesis in the root stele, thus helping sweetpotato plants to block the loading of Na+ into the xylem and to minimize the accumulation of Na+ in the shoots.

Evolutionary relationship of moso bamboo forms and a multihormone regulatory cascade involving culm shape variation.

Moso bamboo (Phyllostachys edulis) known as Mao Zhu (MZ) in Chinese exhibits various forms with distinct morphological characteristics. However, the evolutionary relationship among MZ forms and the mechanisms of culm shape variation are still lacking. Here, the main differences among MZ forms were identified as culm shape variation, which were confirmed by analysing MZ forms (799 bamboo culms) and MZ (458 bamboo culms) populations. To unravel the genetic basis underlying the morphological variations, 20 MZ forms were subjected to whole-genome resequencing. Further analysis yielded 3 230 107 high-quality SNPs and uncovered low genetic diversity and high genotype heterozygosity associated with MZ forms' formation. By integrating the SNP data of 427 MZ individuals representing 15 geographic regions, the origins of eight MZ forms were successfully traced using the phylogenetic tree and the identified common heterozygous loci. Meanwhile, transcriptomic analysis was performed using shoots from MZ and its two forms with culm shape variation. The results, combined with genomic analyses, demonstrated that hormone signalling related genes played crucial roles in culm variation. Co-expression network analysis uncovered genes associated with multiple plant hormone signal transduction, especially auxin and cytokinin were involved in culm shape variation. Furthermore, the regulatory relationships of a specific transcription factor and their target genes associated with auxin and ethylene signalling were validated by yeast one-hybrid, electrophoretic mobility shift assays, and dual-luciferase reporter. Overall, this study provides important insights into the culm shape variation formation in bamboo, which facilitates to breed new varieties with novel culms.

Integrated multi-omic approach reveals the effect of a Graminaceae-derived biostimulant and its lighter fraction on salt-stressed lettuce plants

Plant biostimulants are widely applied in agriculture for their ability to improve plant fitness. In the present work, the impact of Graminaceae-derived protein hydrolysate (P) and its lighter molecular fraction F3 (< 1 kDa) on lettuce plants, subjected to either no salt or high salt conditions, was investigated through the combination of metabolomics and transcriptomics. The results showed that both treatments significantly modulated the transcriptome and metabolome of plants under salinity stress, highlighting an induction of the hormonal response. Nevertheless, P and F3 also displayed several peculiarities. F3 specifically modulated the response to ethylene and MAPK signaling pathway, whereas P treatment induced a down-accumulation of secondary metabolites, albeit genes controlling the biosynthesis of osmoprotectants and antioxidants were up-regulated. Moreover, according with the auxin response modulation, P promoted cell wall biogenesis and plasticity in salt-stressed plants. Notably, our data also outlined an epigenetic control of gene expression induced by P treatment. Contrarily, experimental data are just partially in agreement when not stressed plants, treated with P or F3, were considered. Indeed, the reduced accumulation of secondary metabolites and the analyses of hormone pathways modulation would suggest a preferential allocation of resources towards growth, that is not coherent with the down-regulation of the photosynthetic machinery, the CO2 assimilation rate and leaves biomass. In conclusion, our data demonstrate that, although they might activate different mechanisms, both the P and F3 can result in similar benefits, as far as the accumulation of protective osmolytes and the enhanced tolerance to oxidative stress are concerned. Notably, the F3 fraction exhibits slightly greater growth promotion effects under high salt conditions. Most importantly, this research further corroborates that biostimulants’ mode of action is dependent on plants’ physiological status and their composition, underscoring the importance of investigating the bioactivity of the different molecular components to design tailored applications for the agricultural practice.

The YABBY Transcription Factor, SlYABBY2a, Positively Regulates Fruit Septum Development and Ripening in Tomatoes.

The tomato fruit is a complex organ and is composed of various structures from the inside out, such as columella, septum, and placenta. However, our understanding of the development and function of these internal structures remains limited. In this study, we identified a plant-specific YABBY protein, SlYABBY2a, in the tomato (Solanum lycopersicum). SlYABBY2a exhibits relatively high expression levels among the nine YABBY genes in tomatoes and shows specific expression in the septum of the fruit. Through the use of a gene-editing technique performed by CRISPR/Cas9, we noticed defects in septum development in the Slyabby2a mutant fruits, leading to the inward concavity of the fruit pericarp and delayed septum ripening. Notably, the expression levels of key genes involved in auxin (SlFZY4, SlFZY5, and SlFZY6) and ethylene (SlACS2) biosynthesis were significantly downregulated in the septum of the Slalkbh10b mutants. Furthermore, the promoter activity of SlYABBY2a was regulated by the ripening regulator, SlTAGL1, in vivo. In summary, these discoveries provide insights into the positive regulation of SlYABBY2a on septum development and ripening and furnish evidence of the coordinated regulation of the auxin and ethylene signaling pathways in the ripening process, which expands our comprehension of septum development in the internal structure of the fruit.

The Marssonina rosae effector MrSEP43 suppresses immunity in rose by targeting the orphan protein RcBROG.

Rose black spot disease, caused by Marssonina rosae (syn. Diplocarpon rosae), is one of the most widespread diseases of field-grown roses worldwide. Pathogens have been found to interfere with or stimulate plant immune responses by secreting effectors. However, the molecular mechanism involved in inhibition of the rose immune response by M. rosae effectors remains poorly understood. Here, we identified the effector MrSEP43, which plays a pivotal role in promoting the virulence of M. rosae and enhancing rose susceptibility to infection by reducing callose deposition, H2O2 accumulation, and the expression of defense genes in the jasmonic acid signaling pathway. Yeast two-hybrid, bimolecular fluorescence complementation, and split luciferase assays showed that MrSEP43 interacted with the rose orphan protein RcBROG. RcBROG, a positive regulator of defense against M. rosae, enhanced rose resistance by increasing callose deposition, H2O2 accumulation, and the expression of RcERF1 in the ethylene signaling pathway. Overall, our findings suggest that the M. rosae virulence effector MrSEP43 specifically targets the orphan protein RcBROG to suppress the rose immune response to M. rosae. These results provide new insights into how M. rosae manipulates and successfully colonizes rose leaves, and are essential for preventing the breakdown of resistance to rose black spot disease.

Wheat TaAP2/ERF Genes Regulate Heat Tolerance Through Ethylene Signaling at Grain-Filling Stage

AbstractWheat is a globally important crop, and its production is critically challenged by heat stress. To understand the heat tolerance mechanism at grain-filling stage in wheat, two genotypes, W156 (tolerant) and Brazil 32 (susceptible) were evaluated for their morphological responses and expressions of TaAP2/ERF super-family transcription factor genes under heat stress (at 37/27 °C) at 11 days and 13 days post-anthesis. The W156 showed significantly higher thousand kernel weight (TKW), chlorophyll fluorescence (Fv/Fm) and delayed senescence of flag leaf and exposed peduncle. Twenty-two differentially expressed genes (DEGs) were selected from in silico expression analysis of 630 TaAP2/ERF genes under abiotic stress and their RT-qPCR expression validation identified twenty major DEGs responsive to heat stress. Co-expression network analysis of these DEGs identified hub TF genes including TraesCS1A02G221900, TraesCS6D02G324200, TraesCS6B02G331000, TraesCS4D02G298600, TraesCS5B02G193200, and TraesCS1A02G058400. Gene Ontology analysis and Gene Set Enrichment Analysis further revealed that 16 (80%) out of the 20 DEGs were involved in the ethylene-activated signaling pathway. Those DEGs involved in ethylene signaling pathway were further validated in an additional pair of contrasting genotypes (Perenjori and Yitpi). Therefore, heat tolerance regulated by TaAP2/ERF genes at grain filling stage of wheat may be mainly through ethylene signaling pathway while maintaining seed development under heat stress.

IDD10-NAC079 transcription factor complex regulates sheath blight resistance by inhibiting ethylene signaling in rice

IntroductionRhizoctonia solani Kühn is a pathogen causing rice sheath blight (ShB). Ammonium transporter 1 (AMT1) promotes resistance of rice to ShB by activating ethylene signaling. However, how AMT1 activates ethylene signaling remains unclear. ObjectiveIn this study, the indeterminate domain 10 (IDD10)-NAC079 interaction model was used to investigate whether ethylene signaling is modulated downstream of ammonium signaling and modulates ammonium-mediated ShB resistance. MethodsRT-qPCR assay was used to identify the relative expression levels of nitrogen and ethylene related genes. Yeast two-hybrid assays, Bimolecular fluorescence complementation (BiFC) and Co-immunoprecipitation (Co-IP) assay were conducted to verify the IDD10-NAC079-calcineurin B-like interacting protein kinase 31 (CIPK31) transcriptional complex. Yeast one-hybrid assay, Chromatin immunoprecipitation (ChIP) assay, and Electrophoretic mobility shift assay (EMSA) were used to verify whether ETR2 was activated by IDD10 and NAC079. Ethylene quantification assay was used to verify ethylene content in IDD10 transgenic plants. Genetic analysis is used to detect the response of IDD10, NAC079 and CIPK31 to ShB infestation. ResultsIDD10-NAC079 forms a transcription complex that activates ETR2 to inhibit the ethylene signaling pathway to negatively regulating ShB resistance. CIPK31 interacts and phosphorylates NAC079 to enhance its transcriptional activation activity. In addition, AMT1-mediated ammonium absorption and subsequent N assimilation inhibit the expression of IDD10 and CIPK31 to activate the ethylene signaling pathway, which positively regulates ShB resistance. ConclusionThe study identified the link between ammonium and ethylene signaling and improved the understanding of the rice resistance mechanism.

A pattern for the early, middle, and late phase of tea chrysanthemum response to Fusarium oxysporum.

Chrysanthemum morifolium is cultivated worldwide and has high ornamental, tea, and medicinal value. With the increasing area of chrysanthemum cultivation and years of continuous cropping, Fusarium wilt disease frequently occurs in various production areas, seriously affecting the quality and yield and causing huge economic losses. However, the molecular response mechanism of Fusarium wilt infection remains unclear, which limits the molecular breeding process for disease resistance in chrysanthemums. In the present study, we analyzed the molecular response mechanisms of 'Huangju,' one of the tea chrysanthemum cultivars severely infested with Fusarium wilt in the field at the early, middle, and late phases of F. oxysporum infestation. 'Huangju' responded to the infestation mainly through galactose metabolism, plant-pathogen interaction, auxin, abscisic acid, and ethylene signalling in the early phase; galactose metabolism, plant-pathogen interaction, auxin, salicylic acid signal, and certain transcription factors (e.g., CmWRKY48) in the middle phase; and galactose metabolism in the late phase. Notably, the galactose metabolism was important in the early, middle, and late phases of 'Huangju' response to F. oxysporum. Meanwhile, the phytohormone auxin was involved in the early and middle responses. Furthermore, silencing of CmWRKY48 in 'Huangju' resulted in resistance to F. oxysporum. Our results revealed a new molecular pattern for chrysanthemum in response to Fusarium wilt in the early, middle, and late phases, providing a foundation for the molecular breeding of chrysanthemum for disease resistance.

The Arabidopsis RTH plays an important role in regulation of iron (Fe) absorption and transport.

RTH may activate Fe assimilation related genes to promote Fe absorption, transport and accumulation in Arabidopsis. Iron (Fe) is an important nutrient element. The Fe absorption and transport in plants are well investigated over the past decade. Our previous work indicated that RTE1-HOMOLOG (RTH), the homologous gene of reversion-to-ethylene sensitivity 1 (RTE1), plays a role in ethylene signaling pathway. However, its function in Fe absorption and transport is largely unknown. In the present study, we found that RTH was expressed in absorptive tissue and conducting tissue, including root hairs, root vascular bundle, and leaf veins. Under high Fe concentration, the seedling growth of rth-1 mutant was better, while the RTH overexpression lines were retarded compared to the wild type (Col-0). When treated with EDTA-Fe3+ (400μM), the chlorophyll content and ion leakage rate were higher and lower in rth-1 than those of Col-0, respectively. By contrast, the chlorophyll contents and ion leakage rates of RTH overexpression lines were decreased and hastened compared with Col-0, respectively. Fe measurement indicated that the Fe contents of rth-1 were lower than those of Col-0, whereas those of RTH overexpression lines were comparably higher. Gene expression analysis revealed that Fe absorption and transport genes AHA2, IRT1, FIT, FPN1, and YSL1 decreased in rth-1 but increased in RTH overexpression lines compared with Col-0. Additionally, Y2H (yeast two-hybrid) and BiFC (bimolecular fluorescence complementation) assays showed that RTH can physically interact with hemoglobin 1 (HB1) and HB2. All these findings suggest that RTH may play an important role in regulation of Fe absorption, transport, and accumulation in Arabidopsis.

Ethylene biosynthesis and signal transduction during ripening and softening in non-climacteric fruits: an overview.

In recent years, the ethylene-mediated ripening and softening of non-climacteric fruits have been widely mentioned. In this paper, recent research into the ethylene-mediated ripening and softening of non-climacteric fruits is summarized, including the involvement of ethylene biosynthesis and signal transduction. In addition, detailed studies on how ethylene interacts with other hormones to regulate the ripening and softening of non-climacteric fruits are also reviewed. These findings reveal that many regulators of ethylene biosynthesis and signal transduction are linked with the ripening and softening of non-climacteric fruits. Meanwhile, the perspectives of future research on the regulation of ethylene in non-climacteric fruit are also proposed. The overview of the progress of ethylene on the ripening and softening of non-climacteric fruit will aid in the identification and characterization of key genes associated with ethylene perception and signal transduction during non-climacteric fruit ripening and softening.

Shade stress triggers ethylene biosynthesis to accelerate soybean senescence and impede nitrogen remobilization

In gramineae-soybean intercropping systems, shade stress caused by taller plants impacts soybean growth specifically during the reproductive stage. However, the effects of shade stress on soybean senescence remain largely unexplored. In this research, we applied artificial shade treatments with intensities of 75% (S75) and 50% (S50) to soybean plants at the onset of flowering to simulate the shade stress experienced by soybeans in the traditional and optimized maize-soybean intercropping systems, respectively. Compared to the normal light control, both shade treatments led to a rapid decline in the dry matter content of soybean vegetative organs and accelerated their abscission. Moreover, shade treatments triggered the degradation of chlorophyll and soluble proteins in leaves and increased the expression of genes associated with leaf senescence. Metabolic profiling further revealed that ethylene biosynthesis and signal transduction were induced by shade treatment. In addition, the examination of nitrogen content demonstrated that shade treatments impeded the remobilization of nitrogen in vegetative tissues, consequently reducing the seed nitrogen harvest. It's worth noting that these negative effects were less pronounced under the S50 treatment compared to the S75 treatment. Taken together, this research demonstrates that shade stress during the reproductive stage accelerates soybean senescence and impedes nitrogen remobilization, while optimizing the field layout to improve soybean growth light conditions could mitigate these challenges in the maize-soybean intercropping system.

Candidate genes conferring ethylene-response in cultivated peanuts determined by BSA-seq and fine-mapping

Ethylene plays essential roles in plant growth, development and stress responses. The ethylene signaling pathway and molecular mechanism have been studied extensively in Arabidopsis and rice but limited in peanuts. Here, we established a sand-culture method to screen pingyangmycin mutagenized peanut lines based on their specific response to ethylene (“triple response“). An ethylene-insensitive mutant, inhibition of peanut hypocotyl elongation 1 (iph1), was identified that showed reduced sensitivity to ethylene in both hypocotyl elongation and root growth. Through bulked segregant analysis sequencing, a major gene related to iph1, named AhIPH1, was preliminarily mapped at the chromosome Arahy.01, and further narrowed to a 450-kb genomic region through substitution mapping strategy. A total of 7014 genes were differentially expressed among the ACC treatment through RNA-seq analysis, of which only the Arahy.5BLU0Q gene in the candidate mapping interval was differentially expressed between WT and mutant iph1. Integrating sequence variations, functional annotation and transcriptome analysis revealed that a predicated gene, Arahy.5BLU0Q, encoding SNF1 protein kinase, may be the candidate gene for AhIPH1. This gene contained two single-nucleotide polymorphisms at promoter region and was more highly expressed in iph1 than WT. Our findings reveal a novel ethylene-responsive gene, which provides a theoretical foundation and new genetic resources for the mechanism of ethylene signaling in peanuts.

A chromosome-level genome assembly for the amphibious plant Rorippa aquatica reveals its allotetraploid origin and mechanisms of heterophylly upon submergence

The ability to respond to varying environments is crucial for sessile organisms such as plants. The amphibious plant Rorippa aquatica exhibits a striking type of phenotypic plasticity known as heterophylly, a phenomenon in which leaf form is altered in response to environmental factors. However, the underlying molecular mechanisms of heterophylly are yet to be fully understood. To uncover the genetic basis and analyze the evolutionary processes driving heterophylly in R. aquatica, we assembled the chromosome-level genome of the species. Comparative chromosome painting and chromosomal genomics revealed that allopolyploidization and subsequent post-polyploid descending dysploidy occurred during the speciation of R. aquatica. Based on the obtained genomic data, the transcriptome analyses revealed that ethylene signaling plays a central role in regulating heterophylly under submerged conditions, with blue light signaling acting as an attenuator of ethylene signal. The assembled R. aquatica reference genome provides insights into the molecular mechanisms and evolution of heterophylly.

Unique molecular mechanisms revealed for the effects of temperature, CA, ethylene exposure, and 1-MCP on postharvest senescence of broccoli

The management of postharvest broccoli (Brassica oleracea L. var. italica) exemplifies a crucial element in ensuring agricultural sustainability and food preservation. The main aim of our study was to investigate the physiological and molecular factors that influence the shelf life of broccoli by employing several technologies known to influence its deterioration, namely controlled atmosphere (CA), 1-methylcyclopropene (1-MCP), and ethylene interventions. Controlled atmosphere (CA) and 1-methylcyclopropene (1-MCP) delay the senescence process whereas ethylene promotes broccoli senescence. The study involved physiological assessments to investigate the broccoli senescence patterns as influenced by temperature, and the effects of CA, 1-MCP, and ethylene on the shelf life of broccoli. Concurrently, RNA sequencing and subsequent analysis improved our understanding of the intricate molecular mechanisms behind postharvest senescence. The application of 1-MCP and CA demonstrated significant delays in the senescence process, affirming their effectiveness in maintaining broccoli quality during postharvest storage. We found that the MAPK pathway during 1-MCP treatment was involved in stress and defense responses by expression of genes like WRKY33, WRKY29, EIN3, PYL4, Catalase 2-like (CAT2 like), and SRK2E. Furthermore, alterations in auxin-responsive genes like IAA, SAUR21, and SAUR36 highlight the differential modulation of ethylene and auxin signaling pathways. A subsequent experiment demonstrated that in postharvest broccoli, exogenous auxin promotes senescence and auxin inhibitors retard senescence. Downregulation of key enzymatic genes, including UTP-glucose-1-phosphate uridylyltransferases, during CA treatment points to inhibition of glycolysis, which might be one of the mechanisms to enhance the shelf life of harvested products and delay senescence. Senescence-associated gene expression patterns suggested stage-specific connections that need additional investigation. This study offers valuable insights into the field of postharvest management, providing practical knowledge by identifying target genes for enhancing broccoli storage life and mitigating food waste.

Analysis of Ethylene Signal Regulating Sucrose Metabolism in Strawberry Fruits Based on RNA-seq.

Ethylene is a key hormone that regulates the maturation and quality formation of horticultural crops, but its effects on non-respiratory climacteric fruits such as strawberries are not yet clear. In this study, strawberry fruits were treated with exogenous ethephon (ETH) and 1-methylcyclopropene (1-MCP). It was found that ETH treatment increased the soluble solids and anthocyanin content of the fruits, reduced hardness, and decreased organic acid content, while 1-MCP treatment inhibited these processes. Transcriptome analysis revealed that differentially expressed genes (DEGs) were enriched in the starch-sucrose metabolism pathway. qRT-PCR results further showed significant changes in the expression levels of sucrose metabolism genes, confirming the influence of ethylene signals on soluble sugar accumulation during strawberry fruit development. This study elucidates the quality changes and molecular mechanisms of ethylene signal in the development of strawberry fruits, providing some key targets and theoretical support for guiding strawberry cultivation and variety improvement.

Identification and Expression Analysis of Transcription Factors in Carallia Brachiata Genome

Transcription factors are important regulatory factors in gene expression. To explore the role of transcription factors in the adaptation of Carallia brachiata to its environment, this study identified the transcription factor family across the genome and analyzed their expression in eight tissues (roots, stems, leaves, flowers, ovules, fruits, seeds, embryos). The results showed that a total of 2322 transcription factor from 91 families were identified. They were significantly enriched in 12 pathways including plant signal transduction, circadian rthythm, MAPK signaling pathway-plant and plant-pathogen interaction etc. Most genes were involved in environmental information processing and environmental adaptation through signal transduction. The results of expression analysis showed 204 genes were tissue-specific. Genes that were responsible for the signal transduction of cytokinine, auxin, gibberellin, jasmonic acid, salicylic acid were mainly expressed in root, stem, leaf, flower, ovule and fruit while the genes that involve in ethylene and abscisic acid signal transduction were only expressed in seed and embryo. This study suggested that the transcription factors regulated different tissues of C. brachiata by participating in different hormone response pathways, so as to regulate plant growth and development.