Acid Metabolism Research Articles

Sequential bioaugmentation of the dominant microorganisms to improve the fermentation and flavor of cereal vinegar

Traditional cereal vinegars are fermented by microorganisms that are spontaneously enriched, leading to uncertainty in regulating the fermentation process and flavor. The objective of this study was to elucidate the impact of the predominant microorganisms, provenly Lactobacillus helveticus and Acetobacter pasteurianus, on the solid-state fermentation (SSF) and flavor profile of cereal vinegar by several bioaugmentation strategies. The results indicated that the sequential bioaugmentation of predominant microorganisms improved the utilization of raw material and most key flavor compounds. Through sequential bioaugmentation strategy, bacterial diversity was regulated due to minimizing acetic acid inhibition in the early stages, and the non-volatile acid was targetedly improved by Lactobacillus. Furthermore, the important flavor of non-volatile acid, esters, acetoin, and tetramethyl-pyrazine content was enhanced by sequential bioaugmentation. Therefore, the sensory score on taste and odor were improved. These results provide a reference for the targeted regulation of the SSF and the flavor quality of cereal vinegar.

Nephro- and Cardiotoxic Effects of Etoricoxib: Insights into Arachidonic Acid Metabolism and Beta-Adrenergic Receptor Expression in Experimental Mice

Background: Etoricoxib is a widely used anti-inflammatory drug, but its safety profile concerning cardiovascular and renal health remains inadequately explored. This study aimed to assess the nephro- and cardiotoxic effects of etoricoxib in a murine model, with a focus on its impact on arachidonic acid-metabolizing enzymes and beta-adrenergic receptors associated with drug-induced toxicity. Methods: Thirty-five BALB/C mice were randomly assigned to five groups: control, low-dose etoricoxib, high-dose etoricoxib, low-dose celecoxib, and high-dose celecoxib (a well-known nephro- and cardiotoxic NSAID). The treatments were administered for 28 days, after which hearts and kidneys were excised for physical and histopathological analysis, and the expression of arachidonic acid-metabolizing enzymes (cytochrome P450s, lipoxygenases, cyclooxygenases) and beta-1 adrenergic receptor (adrb1) and angiotensin-converting enzyme (ace2) genes were quantified using quantitative reverse transcription PCR (qRT-PCR). Results: Etoricoxib administration resulted in dose-dependent nephro- and cardiotoxic effects. Renal histology revealed glomerular atrophy or hypertrophy and significant damage to the proximal and distal convoluted tubules, including epithelial flattening, cytoplasmic vacuolation, and luminal widening. Cardiac analysis showed disorganized muscle fibers and hyaline degeneration. These changes were associated with altered gene expression: the downregulation of cox2, cyp1a1, and cyp2c29 in the kidneys and the upregulation of cyp4a12, cox2, and adrb1, along with the downregulation of cyp2c29 and ace2 in the heart. Conclusions: Etoricoxib induces nephro- and cardiotoxicity, marked by alterations in arachidonic acid metabolism and beta-adrenergic signaling pathways. The drug affects the expression of arachidonic acid-metabolizing enzymes and adrb1 in the heart while downregulating cox2 and other related enzymes in the kidneys. These findings underscore the need for caution when prescribing etoricoxib, particularly in patients with pre-existing renal or cardiac conditions.

Multi-omics after O-GlcNAc alteration identified cellular processes promoting aneuploidy after loss of O-GlcNAc transferase

Pharmacologic or genetic manipulation of O-GlcNAcylation, an intracellular, single sugar post-translational modification, are difficult to interpret due to the pleotropic nature of O-GlcNAc and the vast signaling pathways it regulates. To address this issue, we employed either OGT (O-GlcNAc transferase), OGA (O-GlcNAcase) liver knockouts, or pharmacological inhibition of OGA coupled with multi-Omics analysis and bioinformatics. We identified numerous genes, proteins, phospho-proteins, or metabolites that were either inversely or equivalently changed between conditions. Moreover, we identified pathways in OGT knockout samples associated with increased aneuploidy. To test and validate these pathways, we induced liver growth in OGT knockouts by partial hepatectomy. OGT knockout livers showed a robust aneuploidy phenotype with disruptions in mitosis, nutrient sensing, protein metabolism/amino acid metabolism, stress response, and HIPPO signaling demonstrating how OGT is essential in controlling aneuploidy pathways. Moreover, these data show how a multi-Omics platform can discern how OGT can fine-tune multiple cellular pathways involved in in aneuploidy.

Influence of different growth conditions on the composition and acidogenicity of saliva-derived microcosm biofilm and their effects on enamel demineralization

This study compared the influence of growth conditions on the composition and acidogenicity of saliva-derived microcosm biofilms and enamel demineralization. Biofilms grown in sucrose-supplemented modified McBain medium, containing 25/50 mmol/L PIPES (buffer), under anaerobiosis/microaerophilia, for 3 and 7 days were evaluated for their acidogenicity, microbial composition, matrix, and enamel mineral content. The viability of total lactobacilli was higher in the group containing 25 mmol/L PIPES grown under anaerobiosis, which also showed lower pH values. The viability of total streptococci and total microorganisms was significantly higher at 7 days in the groups with 50 mmol/L PIPES than at 3 days, regardless of the incubation atmosphere. No significant differences were observed in lactic acid, calcium, superficial hardness loss, or lesion depth. In conclusion, the incubation atmosphere, buffer content in the growth media, and duration of biofilm formation displayed species-varied influence on microcosm biofilms, without causing significant changes in acid metabolism or enamel demineralization.

Transcriptome and metabolome reveal the molecular mechanism of quality formation in different planting areas of Ziziphus jujuba Mill. ‘Jingudazao’ fruit

Both environmental and genetic factors have important influences on the quality formation of jujube fruit. To elucidate the molecular mechanism of fruit quality formation with the effects of soil and meteorological factors, transcriptome and metabolome analysis was conducted on Ziziphus jujuba Mill. ‘Jingudazao’ (JG) fruits were harvested from the three areas, Hebei (HB), Shanxi (SX), and Xinjiang (XJ) at the half-red stage. Firstly, meteorological factors and soil conditions have significant effects on jujube fruit quality characteristics. In compared groups, 331, 295, and 297 differentially accumulated metabolites (DAMs) were identified, while the principal DAMs pertaining to carbohydrates, organic acids, amino acids, derivatives, etc. showed that JG_HB had fewer DAMs than JG_XJ and JG_SX. Among them, 20 differentially expressed genes (DEGs), 13 DAMs, and their derivatives participated in carbohydrates and acid metabolism. In addition, two DEGs and seven DAMs were involved in flavonoid biosynthesis. The results provide a valuable and theoretical foundation for the ecological planting and cultivation of jujube.

A comparative metabolomics study of delayed-harvested and pumpkin grafted cucumbers

Cucumber is a widely consumed vegetable crop known for its rich nutrient composition and distinctive flavor, influenced by both volatile and non-volatile compounds. Grafting and delayed harvesting are crucial strategies for increasing cucumber yield. The present study investigates the impact of delayed harvesting at different developmental stages and grafting on the metabolic profile, flavor, and overall quality of cucumber fruits Yuxiu 2 (YX) using UPLC-MS/MS and GC-MS/MS techniques. The results indicate that delayed harvesting of YX led to significant increases in length, diameter, and weight from 12 to 24 days after pollination (DAP), with minimal growth beyond 24 DAP. However, grafting did not affect these physical parameters compared to self-rooted plants. Furthermore, metabolic profiling reveals that delayed harvesting enhances the concentration of certain non-volatile metabolites, including alkaloids, organic acids, and phenolic acids, while leading to a reduction in flavonoid contents. Overall, 140 non-volatile and 26 volatile differential metabolites were screened at three developmental stages. Notably, four new organic acids (6-amino hexanoic acid, 5-amino valeric acid, 1-hydroxy-2-naphthoic acid, and succinic semialdehyde) and three novel alkaloids (3-indole acetonitrile, epinephrine, and serotonin) were identified. Volatile compounds, such as aldehydes, esters, terpenes, alcohols, and ketones, exhibit a peak in concentration at 24 DAP, followed by a decline. The characteristic cucumber flavor compound, (E,Z)-2,6-nonadienal, remains consistent across all developmental stages. In grafted cucumber fruits, a total of 113 non-volatile and 11 volatile differential metabolites were screened, and among them, ten unique non-volatile metabolites were detected in grafted fruits, contributing to the sour and bitter taste of cucumbers. Moreover, some of the metabolites like (1S,4S,4aR)-1-isopropyl-4-methyl-7-methylene-1,2,3,4,4a,5,6,7-octahydronaphthalene with pentylenetetrazol contribute to an undesirable camphor-like odor. The study concludes that while delayed harvesting and grafting practices can increase cucumber yield, they also significantly alter the fruit’s metabolic profile, impacting taste and flavor.

Microbial Community Dynamics and Metabolite Changes during Wheat Starch Slurry Fermentation.

Wheat starch fermentation slurry is the main substrate for producing Ganmianpi, a traditional Chinese fermented wheat starch-based noodle. In the present work, the microbial population dynamics and metabolite changes in wheat starch fermentation slurry at different fermentation times (0, 1, 2, 3, and 4 days) were measured by using high-throughput sequencing analysis and headspace solid-phase microextraction gas chromatography-mass spectrometry (HS-SPME/GC-MS) methods. The texture and sensory properties of Ganmianpi made from fermented starch slurry are also evaluated. The results showed that Latilactobacillus curvatus and Leuconostoc citreum were the dominant bacteria in wheat starch fermentation slurry, while Saccharomyces cerevisiae and Kazachstania wufongensis were identified as the main species of fungi. With the extension of fermentation time, the reducing sugar content first increased and then decreased, when the titratable acidity content showed an increasing trend, and the nonvolatile acid was significantly higher than the volatile acid. A total of 62 volatile flavor compounds were identified, and the highest content is alcohols, followed by acids. Fermentation significantly reduced the hardness and chewiness of Ganmianpi, and increased its resilience and cohesiveness. Ganmianpi made from fermented starch slurry for two and three days showed a higher sensory score than other samples. The present study is expected to provide a theoretical basis for exploiting the strains with potential for commercial application as starter cultures and quality improvement of Ganmianpi.

Foliar application of sodium selenite affects the growth, antioxidant system, and fruit quality of strawberry.

Selenium (Se) plays a vital role in various physiological processes in plants and is regarded as an essential micronutrient for human health as well. In this study, sodium selenite solution at 10, 40, 70, and 100 mg·L-1 concentrations was foliar sprayed, and the strawberry plant growth, antioxidant system, and fruit quality with an emphasis on sugar and acid content were assessed. The results showed that 10 mg·L-1 of sodium selenite treatment promoted plant growth, while all the treated concentrations could enhance photosynthesis, the antioxidant system in leaves, the content of Se, and ascorbic acid in fruits. More importantly, 40 mg·L-1 sodium selenite treatment significantly increased fruit weight, total soluble solid, total phenolic content, and anthocyanins, as well as improved the shape index. Furthermore, it decreased the total flavonoid and proanthocyanidin content. Particularly, sodium selenite treatment at 40 and 70 mg·L-1 largely increased the ratio of soluble sugars to titratable acid. The changes of predominant sugars and organic acids during fruit development were further investigated. The sucrose, fructose, and glucose content was upregulated by sodium selenite treatment through upregulating the activities of sucrose phosphate synthase (SPS) and acid invertase, as well as the FaSPS expression. In addition, sodium selenite treatment inhibited the activity of citrate synthase and phosphoenolpyruvate carboxylase, rather than modulating their transcript levels to reduce the citric acid content. This work presented a potentially efficient approach to enhance plant growth and fruit quality and supplement Se in strawberry, providing insights into the mechanism of regulating sugar and acid metabolism by Se.

A Barth Syndrome Patient-Derived D75H Point Mutation in TAFAZZIN Drives Progressive Cardiomyopathy in Mice.

Cardiomyopathy is the predominant defect in Barth syndrome (BTHS) and is caused by a mutation of the X-linked Tafazzin (TAZ) gene, which encodes an enzyme responsible for remodeling mitochondrial cardiolipin. Despite the known importance of mitochondrial dysfunction in BTHS, how specific TAZ mutations cause diverse BTHS heart phenotypes remains poorly understood. We generated a patient-tailored CRISPR/Cas9 knock-in mouse allele (TazPM) that phenocopies BTHS clinical traits. As TazPM males express a stable mutant protein, we assessed cardiac metabolic dysfunction and mitochondrial changes and identified temporally altered cardioprotective signaling effectors. Specifically, juvenile TazPM males exhibit mild left ventricular dilation in systole but have unaltered fatty acid/amino acid metabolism and normal adenosine triphosphate (ATP). This occurs in concert with a hyperactive p53 pathway, elevation of cardioprotective antioxidant pathways, and induced autophagy-mediated early senescence in juvenile TazPM hearts. However, adult TazPM males exhibit chronic heart failure with reduced growth and ejection fraction, cardiac fibrosis, reduced ATP, and suppressed fatty acid/amino acid metabolism. This biphasic changeover from a mild-to-severe heart phenotype coincides with p53 suppression, downregulation of cardioprotective antioxidant pathways, and the onset of terminal senescence in adult TazPM hearts. Herein, we report a BTHS genotype/phenotype correlation and reveal that absent Taz acyltransferase function is sufficient to drive progressive cardiomyopathy.

Smart and bioactive electrospun dressing for accelerating wound healing

The biosafe plant extract, rich in bioactive compounds with anti-inflammatory and antioxidant properties, significantly contributes to wound healing by promoting tissue repair and regeneration. However, the powdered forms of these extracts face several limitations including poor water solubility, limited release in vitro, and compromised waterproofing and breathability. This study successfully developed a smart and bioactive wound dressing through co-electrospinning hydrophobic polylactic acid-H. rhamnoides L. petroleum ether extract with hydrophilic polyvinyl alcohol-Ag (PLAPEE/PVAAg). This innovative dressing exhibits robust properties such as anti-inflammatory and antibacterial activities primarily derived from bioactive compounds in PEE and Ag nanoparticles decorated within PVA nanofibers respectively. Additionally, the dressing’s intelligent waterproofing, breathability, and interstitial fluid absorption create a moist environment that accelerates wound healing. Metabolomics analysis highlights the significance of glycolysis, the TCA cycle, arginine metabolism, linoleic acid/arachidonic acid metabolism, and glutaminolysis in wound healing. These enriched pathways not only stimulate extracellular matrix synthesis specifically collagen but also demonstrate anti-inflammatory properties while promoting angiogenesis thereby enhancing the wound healing process. As an innovative medical dressing, this smart bioactive solution holds immense potential for accelerating wound healing and tissue regeneration while paving a promising path for future advancements in personalized therapeutic strategies for enhanced wound care management.

Mammary adipocytes promote breast tumor cell invasion and angiogenesis in the context of menopause and obesity

The mechanism(s) underlying obesity-related postmenopausal (PM) breast cancer (BC) are not clearly understood. We hypothesized that the increased local presence of ‘obese’ mammary adipocytes within the BC microenvironment promotes the acquisition of an invasive and angiogenic BC cell phenotype and accelerates tumor proliferation and progression. BC cells, treated with primary mammary adipocyte secretome from premenopausal (Pre-M) and PM obese women (ObAdCM; obese adipocyte conditioned-media) upregulated the expression of several pro-tumorigenic factors including VEGF, lipocalin-2 and IL-6. Both Pre-M and PM ObAdCM stimulated endothelial cell recruitment and proliferation and significantly stimulated BC cell proliferation, migration and invasion. IL-6 and LCN2 induced STAT3/Akt signaling in BC cells and STAT3 inhibition abrogated the ObAdCM-stimulated BC cell proliferation and migration. Expression of proangiogenic regulators including VEGF, NRP1, NRP2, IL8RB, TGFβ2, and TSP-1 were found to be differentially regulated in mammary adipocytes from obese PM women. Comparative RNAseq indicated an upregulation of PI3K/Akt signaling, ECM-receptor interactions and lipid/fatty acid metabolism in PM versus Pre-M mammary adipocytes. Our results demonstrate that irrespective of menopausal status, cross-talk between obese mammary adipocytes and BC cells promotes tumor aggressiveness and suggest that targeting the LCN2/IL-6/STAT3 signaling axis may be a useful strategy in obesity-driven breast tumorigenesis.

Succession of microbial community structure in fermented grains during the fermentation of strong-flavor Baijiu and its impact on the metabolism of acids, alcohols, and esters.

The study clarified the succession of microbial community structures in fermented grains (FG) and their association with flavor compounds, along with their potential metabolic functions. The community diversity, functional genera and metabolites in FG were investigated by polyphasic detecting approaches. There are 13 dominant microorganisms in FG (relative abundance > 1%). Moisture and acidity are the key indicators driving the succession of microbial communities in FG. Eight kinds of microorganisms were involved in the metabolism of acid, higher alcohols and ethanol in FG and the abundance of pyruvate dehydrogenase and lactate dehydrogenase were significantly higher than other enzymes (P < 0.05). The results showed that 23 main flavor compounds were the results of the interaction of dominant microorganisms in FG. This study provides a basis for the formation of flavor substances in strong-flavor Baijiu.

Mechanism of improving the quality of table grapes (Vitis. spp.) by exogenous eugenol based on transcriptome

SummaryGrape is widely consumed all over the world for its rich nutritious and health‐promoting effects. While grape berries are prone to quality deterioration after harvest. This study aimed to investigate the effect of eugenol treatment on the quality of grape berries based on the transcriptome. Harvested grape berries were treated with eugenol, and then collected for nutrient component determination and transcriptomics analyses. As a results, treatment with eugenol enhanced the berries firmness, increased the contents of soluble sugars, organic acids and phenolic compounds, improved the antioxidant capacity, and altered gene expression levels of related pathways. Transcriptome analysis revealed 699 differentially expressed genes by 100 mmol L−1 eugenol‐treated berries. Among these DEGs, the transcriptional levels involved in the cell wall, sugar and acid metabolism, phenylpropane metabolism, antioxidant enzymes, and WRKY, MYB family transcription factors were significantly regulated. This study will help to promote the application of eugenol for quality improvements in grape berries.

Regulatory impacts of PPARGC1A gene expression on milk production and cellular metabolism in buffalo mammary epithelial cells

The PPARGC1A gene plays a fundamental role in regulating cellular energy metabolism, including adaptive thermogenesis, mitochondrial biogenesis, adipogenesis, gluconeogenesis, and glucose/fatty acid metabolism. In a previous study, our group investigated seven SNPs in Mediterranean buffalo associated with milk production traits, and the current study builds on this research by exploring the regulatory influences of the PPARGC1A gene in buffalo mammary epithelial cells (BuMECs). Our findings revealed that knockdown of PPARGC1A gene expression significantly affected the growth of BuMECs, including proliferation, cell cycle, and apoptosis. Additionally, we observed downregulated triglyceride secretion after PPARGC1A knockdown. Furthermore, the critical genes related to milk production, including the STATS, BAD, P53, SREBF1, and XDH genes were upregulated after RNAi, while the FABP3 gene, was downregulated. Moreover, Silencing the PPARGC1A gene led to a significant downregulation of β-casein synthesis in BuMECs. Our study provides evidence of the importance of the PPARGC1A gene in regulating cell growth, lipid, and protein metabolism in the buffalo mammary gland. In light of our previous research, the current study underscores the potential of this gene for improving milk production efficiency and overall dairy productivity in buffalo populations.

Using single-sample networks to identify the contrasting patterns of gene interactions and reveal the radiation dose-dependent effects in multiple tissues of spaceflight mice

Transcriptome profiles are sensitive to space stressors and serve as valuable indicators of the biological effects during spaceflight. Herein, we transformed the expression profiles into gene interaction patterns by single-sample networks (SSNs) and performed the integrated analysis on the 301 spaceflight and 290 ground control samples, which were obtained from the GeneLab platform. Specifically, an individual SSN was established for each sample. Based on the topological structures of 591 SSNs, the differentially interacted genes (DIGs) were identified between spaceflights and ground controls. The results showed that spaceflight disrupted the gene interaction patterns in mice and resulted in significant enrichment of biological processes such as protein/amino acid metabolism and nucleic acid (DNA/RNA) metabolism (P-value < 0.05). We observed that the mice exposed to radiation doses within the three intervals (4.66–7.14, 7.592–8.295, 8.49–22.099 mGy) exhibited similar gene interaction patterns. Low and medium doses resulted in changes to the circadian rhythm, while the damaging effects on genetic material became more pronounced in higher doses. The gene interaction patterns in response to space stressors varied among different tissues, with the spleen, lung, and skin being the most responsive to space radiation (P-value < 0.01). The changes observed in gene networks during spaceflight conditions might contribute to the development of various diseases, such as mental disorders, depression, and metabolic disorders, among others. Additionally, organisms activated specific gene networks in response to virus reactivation. We identified several hub genes that were associated with circadian rhythms, suggesting that spaceflight could lead to substantial circadian rhythm dysregulation.

Exploration of carbonyl compounds in red-fleshed kiwifruit wine and perceptual interactions among non-volatile organic acids

Carbonyl compounds are vital constituents that contribute to the flavor profile of alcoholic beverages. We examined 3-nitrophenylhydrazine as a derivatizing reagent for the measurement of 34 carbonyl compounds using UPLC−MS/MS. Adding formic acid and sodium acetate to the mobile phase significantly enhanced the detection limit of carbonyl compounds. The technique exhibited a notable extraction efficiency, yielding recovery percentages ranging from 83.6% to 117.1%, coupled with exceptional sensitivity, as evidenced by detection limits spanning from 0.07 μg/L to 4.80 μg/L. The relative standard deviation was <6.9%, indicating the precision and reliability of the analytical methodology. The method was verified by analyzing carbonyl compounds from red-fleshed kiwifruit wine. Furthermore, sensory assessment revealed that the amalgamation of tartaric acid, malic acid, and citric acid contributes to sour taste perception at sub-threshold concentrations through an additive interaction with supra-threshold non-volatile organic acids such as lactic acid and acetic acid.

Comparison of the physicochemical properties of branded and generic glucose-added maintenance hypotonic infusion fluids to assess the potential for phlebitis and incompatibility with other drugs.

In Japan, the switch from branded to generic infusion fluids has been promoted as a national policy. Recently, as generic products have been in short supply, the switch from generic to branded infusion fluids has increased. However, certain additives for injectable infusion fluids, such as nonvolatile acids like acetic acid and hydrochloric acid, are not required to be listed in the package insert. We hypothesized that the addition of nonvolatile acids may be one of the reasons for the differences in physicochemical properties between the branded and generic infusion fluids. We have previously reported that in other types of electrolyte infusion fluids, a variation in pH can cause incompatibility with other drugs, and variation in titratable acidity and osmolality can lead to phlebitis. Glucose-added maintenance hypotonic infusion fluid (listed as type-3G) is commonly used as a maintenance solution when energy support is needed. However, nonvolatile acid is added to prevent the caramelization of glucose, resulting in higher osmolality and titratable acidity and lower pH. Therefore, we hypothesized that both phlebitis and incompatibility with other drugs are likely to occur; hence, we measured and evaluated the physicochemical properties of branded and generic type-3G infusion fluids. We show that the osmolality, pH, and titratable acidity of all evaluated branded and generic products differed significantly and that these properties should be evaluated together to avoid phlebitis and incompatibility with other drugs when switching between branded and generic type-3G infusion fluids.

Identification of environment-insensitive genes for oil content by combination of transcriptome and genome-wide association analysis in rapeseed.

The primary objective of rapeseed breeding is to enhance oil content, which is predominantly influenced by environmental factors. However, the molecular mechanisms underlying the impact of these environmental factors on oil accumulation remain inadequately elucidated. In this study, we used transcriptome data from two higher (HOC) and two lower oil content (LOC) inbred lines at 35days after pollination (DAP) to investigate genes exhibiting stable expression across three different environments. Meanwhile, a genome-wide association study (GWAS) was utilized to detect candidate genes exhibiting significant associations with seed oil content across three distinct environments. The study found a total of 405 stable differentially expressed genes (DEGs), including 25 involved in lipid/fatty acid metabolism and 14 classified as transcription factors. Among these genes, BnBZIP10-A09, BnMYB61-A06, BnAPA1-A08, BnPAS2-A10, BnLCAT3-C05 and BnKASIII-C09 were also found to exhibit significant associations with oil content across multiple different environments based on GWAS of 50 re-sequenced semi-winter rapeseed inbred lines and previously reported intervals. Otherwise, we revealed the presence of additive effects among BnBZIP10-A09, BnKASIII-C09, BnPAS2-A10 and BnAPA1-A08, resulting in a significant increase in seed oil content. Meanwhile, the majority of these stable DEGs are interconnected either directly or indirectly through co-expression network analysis, thereby giving rise to an elaborate molecular network implicated in the potential regulation of seed oil accumulation and stability. The combination of transcription and GWAS revealed that natural variation in six environment-insensitive gene regions exhibited significant correlations with seed oil content phenotypes. These results provide important molecular marker information for us to further improve oil content accumulation and stability in rapeseed.

An auxin research odyssey: 1989-2023.

The phytohormone auxin is at times called the master regulator of plant processes and has been shown to be a central player in embryo development, the establishment of the polar axis, early aspects of seedling growth, as well as growth and organ formation during later stages of plant development. The Plant Cell has been key, since the inception of the journal, to developing an understanding of auxin biology. Auxin-regulated plant growth control is accomplished by both changes in the levels of active hormones and the sensitivity of plant tissues to these concentration changes. In this historical review, we chart auxin research as it has progressed in key areas and highlight the role The Plant Cell played in these scientific developments. We focus on understanding auxin-responsive genes, transcription factors, reporter constructs, perception, and signal transduction processes. Auxin metabolism is discussed from the development of tryptophan auxotrophic mutants, the molecular biology of conjugate formation and hydrolysis, indole-3-butyric acid metabolism and transport, and key steps in indole-3-acetic acid biosynthesis, catabolism, and transport. This progress leads to an expectation of a more comprehensive understanding of the systems biology of auxin and the spatial and temporal regulation of cellular growth and development.

Prohexadione-calcium improves grape quality by regulating endogenous hormones, sugar and acid metabolism and related enzyme activities in grape berries.

Prohexadione-Calcium (Pro-Ca) plays key roles in improving fruit quality and yield by regulating various aspects of plant growth. However, the effects of how Pro-Ca regulates the regulation of sugar and acid balance and its impact on the production of volatile aroma substances during fruit growth and development are poorly understood. In this study, the Pro-Ca solutions developed at concentrations of 200, 400, 600 and 800 mg·L-1 were sprayed on the entire "Chardonnay" grape tree 22, 42, 62 and 82 days after initial flowering. The values of endogenous hormones, sugar and acid content, enzyme activities and flavor content were then measured in grapes 45, 65, 85 and 105 days (ripeness stage) after the initial flowering. The results showed that Pro-Ca had significant effects on fruits during development, including reducing ABA content, increasing ZT, GA3 and IAA levels, promoting fruit ripening and enhancing enzymes, which are involved in sugar and acid synthesis. Consequently, these effects led to an increase in sugar and acid content in the berries. Particularly during the ripening phase, the application of 600 mg L-1 Pro-Ca resulted in an increase in soluble sugar content of 11.28% and a significant increase in citric acid and malic acid content of 97.80% and 68.86%, respectively. Additionally, Pro-Ca treatment enhanced both the variety and quantity of aroma compounds present in the berries, with the 600 mg·L-1 Pro-Ca treatment showcasing the most favorable impact on volatile aroma compounds in 'Chardonnay' grapes. The levels of aldehydes, esters, alcohols, phenols, acids, ketones, and terpenes were significantly higher under the 600 mg·L-1 Pro-Ca treatment compared to those of control with 51.46 - 423.85% increase. In conclusion, Pro-Ca can regulate the content of endogenous hormones and the activities of enzymes related to sugar and acid metabolism in fruit, thereby increasing the content of soluble sugar and organic acid in fruit and the diversity and concentration of fruit aroma substances. Among them, foliar spraying 600mg · L-1 Pro-Ca has the best effect. In the future, we need to further understand the molecular mechanism of Pro-Ca in grape fruit to lay a solid foundation for quality improvement breeding.