Search Results (20)

Sweet cherry (Prunus avium L.), renowned for its vibrant color and distinctive flavor, enjoys widespread popularity and is planted in temperate climates. This study investigated four short-chilling requirement cultivars in southeast China, which is known as a subtropical climate region, and determined several key fruit qualities, such as color, size, weight, and nutrient attributes (e.g., vitamin C, soluble sugar, organic acid, protein, gibberellin, and brassinolide) at four maturities due to the climate’s effect on the fruit color and the main color substance: anthocyanin accumulation. Therefore, the color index (a*, b*, and L*) and anthocyanin content were determined, and the anthocyanin-related gene expression was quantitative and analyzed using WGCNA. The results showed that the red variety, ‘Jiangnanhong’, exhibited the highest fruit weight and diameter as well as the greatest concentration of cyanidin-3-rutinoside (C3R). Conversely, the yellow variety, ‘Chaoyang 1’, demonstrated higher L* and b* values along with a greater vitamin C content. The research confirmed that C3R is the predominant anthocyanin present in sweet cherries during ripening. Additionally, three genes—LOC110744862, LOC110749842, and LOC110753376—were identified as playing crucial roles in anthocyanin biosynthesis. Anthocyanins significantly influence both the visual appeal and nutritional quality of the fruit. These results provide a theoretical foundation for understanding the differences among sweet cherry varieties in southeast China. Full article

Gleditsia sinensis Lam. (G. sinensis) is a widely known medicinal plant, and its primary bioactive compound is gleditsioside. So far, the significant economic and medicinal value of gleditsioside has been widely recognized. However, the transcriptional regulation governing the biosynthesis of gleditsioside during G. sinensis pod development remains unclear. In this investigation, we observed that gleditsioside levels increased in the pods of G. sinensis from June to November, and we performed a transcriptome analysis to explore the phenomenon. A total of 703 and 162 differentially expressed unigenes (DEGs) were identified in the terpenoid backbone and triterpenoid biosynthesis pathways, respectively. In total, 99 unigenes encoding 17 enzymes, such as ENIN, cytochrome P450 (CYP93E1), and UDP-glucosyltransferase, were identified in the gleditsioside biosynthesis pathway. Moreover, DEGs encoding crucial enzymes, such as HMGCR and AGBH, might determine gleditsioside synthesis during G. sinensis pod development. Interestingly, the gleditsioside synthesis pathway extended to ten metabolic pathways, including the sterol biosynthesis pathway and the brassinolide biosynthesis pathway, among other pathways involved in various hormonal regulations. These pathways shared the same precursor substances (IPP and DMAPP). In addition, weighted gene correlation network analysis (WGCNA) revealed that CL5845.Contig1 (HMGCR) and CL8823.Contig2 (LUP4) might be involved in the gleditsioside biosynthesis. Furthermore, transient transformation validation experiments demonstrated overexpression of CL5845.Contig1 (HMGCR), CL8823.Contig2 (LUP4), and CL11248.Contig4 (CYP93E1) significantly enhanced gleditsioside biosynthesis. Overall, our findings provide important genetic resources for future functional research and new insights into the basic mechanism of saponin biosynthesis. Full article

Dietary energy level plays an important role in animal growth and development. The present study investigated the effect of dietary energy on the growth performance, antioxidative state, and nutrient digestion of meat donkeys. It simultaneously explored the probable reason for cecal microbiota and metabolome. Twelve meat donkeys (male) aged 1 year with a similar weight (150 ± 25 kg) were divided into two treatment groups: low-energy group (E1) and high-energy group (E2). The experiment was divided into a 10-day pre-trial period and a 135-day trial period. Donkeys in the trial periods were fed diets with digestible energy values (in dry matter) of 12.08 and 13.38 MJ/kg (pre-fattening, 1–45 d), 13.01 and 14.27 MJ/kg (mid-fattening, 46–90 d), and 13.54 and 14.93 MJ/kg (late-fattening, 91–135 d). The results show that E1 decreases body weight, average daily gain (ADG), and the digestibility of crude protein, ether extract, neutral detergent fiber, and acid detergent fiber (p < 0.05), but increases cecal acetate and butyrate concentrations, non-esterified fatty acids (NEFAs) in serum, and the ratio of dry matter intake to ADG(F/G). E1 diminished the activities of catalase and glutathione peroxidase, while it increased the content of interleukin, tumor necrosis factor-alpha, and reactive oxygen species (ROS) (p < 0.05). Cecal microbiome showed that the abundance of Firmicutes and Actinobacteria in E1 was significantly lower than in E2 (p = 0.029, p = 0.002), whereas Bacteroidetes was higher (p = 0.005). E1 increased the genera Ruminococcaceae-UCG-004, Acinetobacter, and Rikenellaceae_RC9_gut_group. Meanwhile, cecal metabolome showed that formyl-5-hydroxykynurenamine, chorismate, 3-sulfinoalanine, and 3-isopropylmalate were upregulated in E1, while brassinolide was downregulated. The altered metabolites were mainly enriched in metabolic pathways related to energy metabolism and metabolism to mitigate oxidative stress in the meat donkeys, such as tryptophan metabolism, brassinosteroid biosynthesis metabolism, etc. In conclusion, low-energy diets resulted in a negative energy balance in meat donkeys, resulting in more nutrients being oxidized to provide energy, inducing oxidative stress, and thereby leading to decreasing growth. The reduction in meat donkey growth from low-energy diets was related to changes in cecum microbiota and metabolites. Full article

Rice (Oryza sativa L.) cultivation using direct seeding is susceptible to chilling stress, particularly during seed germination and early seedling growth in the early season of a double cropping system. Alternatively, seed priming with various plant growth-promoting hormones is an effective technique to promote rapid and uniform emergence under chilling stress. Therefore, we evaluated the impact of gibberellin A3 (GA₃) and brassinolide (BR) priming on rice seed emergence, examining their proteomic responses under low-temperature conditions. Results indicated that GA₃ and BR increased the seed germination rate by 22.67% and 7.33% at 72 h and 35% and 15% at 96 h compared to the control (CK), respectively. Furthermore, proteomic analysis identified 2551, 2614, and 2592 differentially expressed proteins (DEPs) in GA, BR, and CK, respectively. Among them, GA exhibited 84 upregulated and 260 downregulated DEPs, while BR showed 112 upregulated and 102 downregulated DEPs, and CK had 123 upregulated and 81 downregulated DEPs. Notably, under chilling stress, both GA₃ and BR are involved in peroxide metabolism, phenylpropanoid biosynthesis, and inositol phosphate metabolism, enhancing antioxidant capacity and providing energy substances for germination. In addition, GA₃ triggers the specific regulation of stress responsive protein activation, GTP activation, and ascorbic acid biosynthesis and promotes the stability and integrity of cell membranes, as well as the synthesis of cell walls, providing physical defense for seeds to resist low temperatures. At the same time, BR triggers specific involvement in ribosome synthesis and amino acid synthesis, promoting biosynthetic ability and metabolic regulation to maintain plant life activities under low-temperature stress. Furthermore, the various genes’ expression (OsJ_16716, OsPAL1, RINO1) confirmed GA₃ and BR involved in peroxide metabolism, phenylpropanoid biosynthesis, and inositol phosphate metabolism, enhancing antioxidant capacity and providing energy substances for germination. This study provides valuable insights into how rice seed embryo responds to and tolerates chilling stress with GA₃ seed priming. Full article

Zelkova schneideriana Hand.-Mazz is a valuable ornamental tree and timber source, whose seedling breeding and large-scale cultivation are restricted by low seed germination and seedling rates. The regulatory mechanisms underlying seed germination and seedling establishment in Z. schneideriana remain unknown. This study conducted metabolomic and transcriptomic analyses of seed germination and seedling establishment in Z. schneideriana. Regular expression of genes and metabolite levels has been observed in plant hormone signal transduction, starch and sucrose metabolism, linoleic acid metabolism, and phenylpropanoid biosynthesis. The reduction in abscisic acid during seed germination may lead to seed release from dormancy. After the seed is released from dormancy, the metabolic levels of auxin, cytokinins, brassinolide, and various sugars are elevated, and they are consumed in large quantities during the seedling establishment stage. Linoleic acid metabolism is gradually activated during seedling establishment. Transcriptome analysis showed that a large number of genes in different metabolic pathways are upregulated during plant establishment, and material metabolism may be accelerated during seedling establishment. Genes regulating carbohydrate metabolism are altered during seed germination and seedling establishment, which may have altered the efficiency of carbohydrate utilization. In addition, the syntheses of lignin monomers and cellulose have different characteristics at different stages. These results provide new insights into the complex mechanisms underlying seed germination and seedling establishment in Z. schneideriana and other woody plants. Full article

Melon (Cucumis melo L.) is a valuable horticultural crop of the Cucurbitaceae family. Downy mildew (DM), caused by Pseudoperonospora cubensis, is a significant inhibitor of the production and quality of melon. Brassinolide (BR) is a new type of phytohormone widely used in cultivation for its broad spectrum of resistance- and defense-mechanism-improving activity. In this study, we applied various exogenous treatments (0.5, 1.0, and 2.0 mg·L⁻¹) of BR at four distinct time periods (6 h, 12 h, 24 h, and 48 h) and explored the impact of BR on physiological indices and the genetic regulation of melon seedling leaves infected by downy-mildew-induced stress. It was mainly observed that a 2.0 mg·L⁻¹ BR concentration effectively promoted the enhanced photosynthetic activity of seedling leaves, and quantitative real-time polymerase chain reaction (qRT-PCR) analysis similarly exhibited an upregulated expression of the predicted regulatory genes of photosystem II (PSII) CmHCF136 (MELO3C023596.2) and CmPsbY (MELO3C010708.2), thus indicating the stability of the PSII reaction center. Furthermore, 2.0 mg·L⁻¹ BR resulted in more photosynthetic pigments (nearly three times more than the chlorophyll contents (264.52%)) as compared to the control and other treatment groups and similarly upregulated the expression trend of the predicted key enzyme genes CmLHCP (MELO3C004214.2) and CmCHLP (MELO3C017176.2) involved in chlorophyll biosynthesis. Meanwhile, the maximum contents of soluble sugars and starch (186.95% and 164.28%) were also maintained, which were similarly triggered by the upregulated expression of the predicted genes CmGlgC (MELO3C006552.2), CmSPS (MELO3C020357.2), and CmPEPC (MELO3C018724.2), thereby maintaining osmotic adjustment and efficiency in eliminating reactive oxygen species. Overall, the exogenous 2.0 mg·L⁻¹ BR exhibited maintained antioxidant activities, plastid membranal stability, and malondialdehyde (MDA) content. The chlorophyll fluorescence parameter values of F0 (42.23%) and Fv/Fm (36.67%) were also noticed to be higher; however, nearly three times higher levels of NPQ (375.86%) and Y (NPQ) (287.10%) were observed at 48 h of treatment as compared to all other group treatments. Increased Rubisco activity was also observed (62.89%), which suggested a significant role for elevated carbon fixation and assimilation and the upregulated expression of regulatory genes linked with Rubisco activity and the PSII reaction process. In short, we deduced that the 2.0 mg·L⁻¹ BR application has an enhancing effect on the genetic modulation of physiological indices of melon plants against downy mildew disease stress. Full article

(1) Background: Brassinosteroids (BRs) are important hormones involved in almost all stages of plant growth and development, and sterol dehydrogenase is a key enzyme involved in BRs biosynthesis. However, the sterol dehydrogenase gene family of Populus yunnanensis Dode (P. yunnanensis) has not been studied. (2) Methods: The PyDET2 (DEETIOLATED2) gene family was identified and analyzed. Three genes were screened based on RNA-seq of the stem tips, and the PyDET2e was further investigated via qRT-PCR (quantitative real-time polymerase chain reaction) and subcellular localization. (3) Results: The 14 DET2 family genes in P. yunnanensis were categorized into four groups, and 10 conserved protein motifs were identified. The gene structure, chromosome distribution, collinearity, and codon preference of all PyDET2 genes in the P. yunnanensis genome were analyzed. The codon preference of this family is towards the A/U ending, which is strongly influenced by natural selection. The PyDET2e gene was expressed at a higher level in September than in July, and it was significantly expressed in stems, stem tips, and leaves. The PyDET2e protein was localized in chloroplasts. (4) Conclusions: The PyDET2e plays an important role in the rapid growth period of P. yunnanensis. This systematic analysis provides a basis for the genome-wide identification of genes related to the brassinolide biosynthesis process in P. yunnanensis, and lays a foundation for the study of the rapid growth mechanism of P. yunnanensis. Full article

Brassinolide (BR) is an important plant hormone that regulates the growth and development of plants and the formation of yield. The yield and quality of latex from Hevea brasiliensis are regulated by phytohormones. The understanding of gene network regulation mechanism of latex formation in rubber trees is still very limited. In this research, the rubber tree variety CATAS73397 was selected to analyze the relationship between BR, water deficit resistance, and latex yield. The results showed that BR improves the vitality of rubber trees under water deficit by increasing the rate of photosynthesis, reducing the seepage of osmotic regulatory substances, increasing the synthesis of energy substances, and improving the antioxidant system. Furthermore, BR increased the yield and quality of latex by reducing the plugging index and elevating the lutoid bursting index without decreasing mercaptan, sucrose, and inorganic phosphorus. This was confirmed by an increased expression of genes related to latex flow. RNA-seq analysis further indicated that DEG encoded proteins were enriched in the MAPK signaling pathway, plant hormone signal transduction and sucrose metabolism. Phytohormone content displayed significant differences, in that trans-Zeatin, ethylene, salicylic acid, kinetin, and cytokinin were induced by BR, whereas auxin, abscisic acid, and gibberellin were not. In summary, the current research lays a foundation for comprehending the molecular mechanism of latex formation in rubber trees and explores the potential candidate genes involved in natural rubber biosynthesis to provide useful information for further research in relevant areas. Full article

Echinochloa crus-galli (L.) P. Beauv (common name: barnyard grass) is a major weed in rice-growing areas and has evolved resistance to multiple herbicides. Florpyrauxifen-benzyl (trade name Rinskor) is a novel synthetic auxin herbicide that was approved in China in 2017 and is widely used in rice production to control resistant weeds, including barnyard grass. We identified a florpyrauxifen-benzyl-resistant E. crus-galli biotype with a resistance index (RI) of 11.89 using screen house herbicide experiments. To understand the phytotoxicity mechanisms of florpyrauxifen-benzyl, we used transcriptomics technologies to compare the gene expression profiles of florpyrauxifen-benzyl treatment on phytohormone transduction between florpyrauxifen-benzyl-resistant and -susceptible barnyard grasses (Echinochloa crus-galli (L.) P. Beauv). A total of 1810 DEGs were identified in the S comparison setting (FTS vs. UTS), and 915 DEGs were identified in the R comparison setting (FTR vs. UTR); 464 genes overlapped between the two comparison groups. Approximately sixty-nine hormone-related DEGs were detected after treatment with florpyrauxifen-benzyl in both R and S biotypes. At 24 h after florpyrauxifen-benzyl treatment, compared with the R biotype, the S biotype showed a stronger auxin response and higher expression of related genes involved in ethylene and abscisic acid biosynthesis and signal transduction. In addition, a brassinolide receptor gene was upregulated after florpyrauxifen-benzyl treatment and had higher expression in the S biotype than in the R biotype. This study is the first transcriptome analysis of the differential effects of florpyrauxifen-benzyl treatment between florpyrauxifen-benzyl-resistant and -susceptible E. crus-galli. It reflects the difference in phytohormone biosynthesis and signal transduction between R and S barnyard grasses in response to florpyrauxifen-benzyl treatment and will be helpful for understanding the phytotoxicity mechanisms of florpyrauxifen-benzyl. Full article

Polygonatum cyrtonema Hua is a traditional Chinese herb propagated using rhizomes, and excessive demand for seedlings and quality deterioration caused by rhizome propagation has highlighted that seed propagation may be an ideal solution to address these issues. However, the molecular mechanisms involved in P. cyrtonema Hua seed germination and emergence stages are not well understood. Therefore, in the present study, we performed transcriptomics combined with hormone dynamics during different seed germination stages, and 54,178 unigenes with an average length of 1390.38 bp (N50 = 1847 bp) were generated. Significant transcriptomic changes were related to plant hormone signal transduction and the starch and carbohydrate pathways. Genes related to ABA(abscisic acid), IAA(Indole acetic acid), and JA(Jasmonic acid) signaling, were downregulated, whereas genes related to ethylene, BR(brassinolide), CTK(Cytokinin), and SA(salicylic acid) biosynthesis and signaling were activated during the germination process. Interestingly, GA biosynthesis- and signaling-related genes were induced during the germination stage but decreased in the emergence stage. In addition, seed germination significantly upregulated the expression of genes associated with starch and sucrose metabolism. Notably, raffinose biosynthesis-related genes were induced, especially during the emergence stage. In total, 1171 transcription factor (TF) genes were found to be differentially expressed. Our results provide new insights into the mechanisms underlying P. cyrtonema Hua seed germination and emergence processes and further research for molecular breeding. Full article

UDP glycosyltransferases (UGTs) play an indispensable role in regulating signaling pathways and intracellular homeostasis in plants by catalyzing the glycosylation of metabolites. To date, the molecular characteristics and potential biological functions of the UGT gene family in pomegranate (Punica granatum L.) remain elusive. In this study, a total of 120 PgUGT genes were identified in the pomegranate genome. Phylogenetic analysis revealed that these PgUGTs were clustered into 15 groups: 13 conserved groups (A–J and L–N) and two newly discovered groups (P and R). Structural analysis showed that most members in the same evolutionary branch shared similar motifs and gene structures. Gene duplication analysis demonstrated that tandem duplication and fragment duplication were the primary driving force for the expansion of the PgUGT family. Expression analysis based on RNA-seq data indicated that PgUGTs exhibited various expression profiles in different pomegranate tissues. We further analyzed the expression patterns of the PgUGTs of groups E and L in the seed coat of the hard-seeded cultivar ‘Dabenzi’ and the soft-seeded cultivar ‘Tunisia’ at different developmental stages. There were eight PgUGTs with high expression levels in the seed coat of both cultivars: PgUGTE10 was highly expressed in inner and outer seed coats; PgUGTE20, PgUGTE21, PgUGTL6, PgUGTL11, and PgUGTL12 were mainly expressed in the inner seed coat; and PgUGTE12 and PgUGTL13 were mainly expressed in the outer seed coat. Interestingly, the relative expression levels of PgUGTE10 and PgUGTL11 in ‘Tunisia’ were higher than in ‘Dabenzi’. In the seedlings, quantitative real-time PCR analysis showed that the expression level of PgUGTE10 was induced by brassinolide treatment, while the expression of PgUGTL11 was up-regulated both by indole-3-acetic acid and the brassinolide treatment. In addition, the expressions of PgUGTE10 and PgUGTL11 were highly correlated with the expression of genes involved in hormone signaling and lignin biosynthesis pathways. These results suggested that PgUGTE10 and PgUGTL11 are potential candidate genes involved in seed hardness development by catalyzing the glycosylation of specific substrates. Full article

Light is vital for plant growth and development, and the germination of many plant seeds and the development of seedlings are very sensitive to the light environment. Under no or low light conditions, pepper seedlings will accelerate the elongation of the hypocotyl to obtain light. To elucidate the molecular mechanism by which light regulates hypocotyl elongation in pepper, RNA sequencing was performed to analyze the hypocotyls and cotyledons of the yellowing mutant R24 under three different light intensity treatments. A total of 35,341 gene were identified; moreover, during the treatment, 9695 new genes and 13,123 differentially expressed genes (DEGs) were observed, respectively. Some genes related to brassino-lide receptor protein kinase BRI1, light capture proteins LHCA and LHCB, and auxin response factor may regulate the response of hot pepper cotyledons and hypocotyls to different light intensity. KEGG functional enrichment analysis revealed that the most abundant pathways were phenylpropane biosynthesis, plant hormone signal transduction, and carbon metabolism. This study provides a valuable reference for understanding the molecular mechanism of pepper’s response to different light intensities at the seedling stage and for improving the local light environment to overcome the hypocotyl elongation of pepper crop under low light conditions. Full article

Pinellia ternata (Thunb.) Druce is a traditional medicinal plant containing a variety of alkaloids, which are important active ingredients. Brassinolide (BR) is a plant hormone that regulates plant response to environmental stress and promotes the accumulation of secondary metabolites in plants. However, the regulatory mechanism of BR-induced alkaloid accumulation in P. ternata is not clear. In this study, we investigated the effects of BR and BR biosynthesis inhibitor (propiconazole, Pcz) treatments on alkaloid biosynthesis in the bulbil of P. ternata. The results showed that total alkaloid content and bulbil yield was enhanced by 90.87% and 29.67% under BR treatment, respectively, compared to the control. We identified 818 (476 up-regulated and 342 down-regulated) and 697 (389 up-regulated and 308 down-regulated) DEGs in the BR-treated and Pcz-treated groups, respectively. Through this annotated data and the Kyoto encyclopedia of genes and genomes (KEGG), the expression patterns of unigenes involved in the ephedrine alkaloid, tropane, piperidine, pyridine alkaloid, indole alkaloid, and isoquinoline alkaloid biosynthesis were observed under BR and Pcz treatments. We identified 11, 8, 2, and 13 unigenes in the ephedrine alkaloid, tropane, piperidine, and pyridine alkaloid, indole alkaloid, and isoquinoline alkaloid biosynthesis, respectively. The expression levels of these unigenes were increased by BR treatment and were decreased by Pcz treatment, compared to the control. The results provided molecular insight into the study of the molecular mechanism of BR-promoted alkaloid biosynthesis. Full article

Premature leaf senescence has a profound influence on crop yield and quality. Here, a stable premature senescence mutant (GSm) was obtained from the common wheat (Triticum aestivum L.) cultivar Chang 6878 by mutagenesis with ethyl methanesulfonate. The differences between the GSm mutant and its wild-type (WT) were analyzed in terms of yield characteristics, photosynthetic fluorescence indices, and senescence-related physiological parameters. RNA sequencing was used to reveal gene expression differences between GSm and WT. The results showed that the yield of GSm was considerably lower than that of WT. The net photosynthetic rate, transpiration rate, maximum quantum yield, non-photochemical quenching coefficient, photosynthetic electron transport rate, soluble protein, peroxidase activity, and catalase activity all remarkably decreased in flag leaves of GSm, whereas malondialdehyde content distinctively increased compared with those of WT. The analysis of differentially expressed genes indicated blockade of chlorophyll and carotenoid biosynthesis, accelerated degradation of chlorophyll, and diminished photosynthetic capacity in mutant leaves; brassinolide might facilitate chlorophyll breakdown and consequently accelerate leaf senescence. NAC genes positively regulated the senescence process. Compared with NAC genes, expression of WRKY and MYB genes was induced earlier in the mutant possibly due to increased levels of reactive oxygen species and plant hormones (e.g., brassinolide, salicylic acid, and jasmonic acid), thereby accelerating leaf senescence. Furthermore, the antioxidant system played a role in minimizing oxidative damage in the mutant. These results provides novel insight into the molecular mechanisms of premature leaf senescence in crops. Full article

Brassinosteroids (BRs) are steroid phytohormones that are known to regulate plant growth and nutrient uptake and distribution. However, how BRs regulate nutrient uptake and balance in legume species is not fully understood. Here, we show that optimal BR levels are required for soybean (Glycine max L.) seedling growth, as treatments with both 24-epicastasterone (24-epiCS) and the BR biosynthesis inhibitor propiconazole (PPZ) inhibit root growth, including primary root elongation and lateral root formation and elongation. Specifically, 24-epiCS and PPZ reduced the total phosphorus and potassium levels in the shoot and affected several minor nutrients, such as magnesium, iron, manganese, and molybdenum. A genome-wide transcriptome analysis identified 3774 and 4273 differentially expressed genes in the root tip after brassinolide and PPZ treatments, respectively. The gene ontology (GO) analysis suggested that genes related to “DNA-replication”, “microtubule-based movement”, and “plant-type cell wall organization” were highly responsive to the brassinolide and PPZ treatments. Furthermore, consistent with the effects on the nutrient concentrations, corresponding mineral transporters were found to be regulated by BR levels, including the GmPHT1s, GmKTs, GmVIT2, GmZIPs, and GmMOT1 genes. Our study demonstrates that optimal BR levels are important for growth and mineral nutrient homeostasis in soybean seedlings. Full article