High‑oxygen-modified atmospheric packaging delays flavor and quality deterioration in fresh-cut broccoli

The purpose of this study was to investigate the impact of high‑oxygen-modified atmospheric packaging (HOMAP) on aroma changes in fresh-cut broccoli during storage and to explore its regulatory mechanisms. The results showed that HOMAP reduced the levels of undesirable aroma substances hexanoic acid, isobutyric acid, cyclopentanone and increased glucosinolate accumulation by inhibiting the expression of arogenate/prephenate dehydratase (ADT), bifunctional aspartate aminotransferase and glutamate/aspartate-prephenate aminotransferase (PAT), thiosulfate/3-mercaptopyruvate Transferase (TST) to reduce the odor of fresh-cut broccoli. HOMAP inhibited the expression of respiratory metabolism related genes 6-phosphate fructokinase 1 (PFK), pyruvate kinase (PK), and NADH-ubiquinone oxidoreductase chain 6 (ND6). In HOMAP group, the low expression of phospholipase C (PLC), phospholipase A1 (PLA1), linoleate 9S-lipoxygenase 1 (LOX1) related to lipid metabolism and the high expression of naringenin 3-dioxygenase (F3H), trans-4-Hydroxycinnamate (C4H), glutaredoxin 3 (GRX3), and thioredoxin 1 (TrX1) in the antioxidant system maintained membrane stability while reducing the occurrence of membrane lipid peroxidation.

Multi-omic analysis of the extension of broccoli quality during storage by folic acid

INTRODUCTION

Folic acid (FA) is a critical metabolite in all living organisms and an important nutritional component of broccoli. Few studies have been conducted on the impact of an exogenous application of FA on the postharvest physiology of fruits and vegetables during storage. In this regard, the mechanism by which an exogenous application of FA extends the postharvest quality of broccoli is unclear.

OBJECTIVE

This study utilized a multicomponent analysis to investigate how an exogenous application of FA effects the postharvest quality of broccoli.

METHODS

Broccoli was soaked in 5 mg/L FA for 10 min and the effect of the treatment on the appearance and nutritional quality of broccoli was evaluated. These data were combined with transcriptomic, metabolomic, and DNA methylation data to provide insight into the potential mechanism by which FA delays senescence.

RESULTS

The FA treatment inhibited the yellowing of broccoli during storage. CHH methylation was identified as the main type of methylation that occurs in broccoli and the FA treatment was found to inhibit DNA methylation, promote the accumulation of endogenous FA and chlorophyl, and inhibit ethylene biosynthesis in stored broccoli. The FA treatment also prevented the formation of off-odors by inhibiting the degradation of glucosinolate.

CONCLUSIONS

FA treatment inhibited the loss of nutrients during the storage of broccoli, delayed its yellowing, and inhibited the generation of off-odors. Our study provides deeper insight into the mechanism by which the postharvest application of FA delays postharvest senescence in broccoli and provides the foundation for further studies of postharvest metabolism in broccoli.

FERMT2 upregulation in CAFs enhances EMT of OSCC and M2 macrophage polarization

OBJECTIVES

FERMT2 upregulation was associated with malignant tumor behaviors, including epithelial-to-mesenchymal (EMT). This study aimed to characterize the expression profile of FERMT2 in oral squamous cell carcinoma (OSCC) and to explore its involvement in the tumor microenvironment sculptured by oral cancer-associated fibroblasts (OCAFs).

MATERIALS

Previous bulk-seq (TCGA-HNSC) and single-cell RNA-seq data sets were retrieved for bioinformatic analysis. Human OSCC lines SCC15 and CAL27, primary normal oral fibroblasts (NOFs), OCAFs, and THP-1 cells were used for intro studies.

RESULTS

FERMT2 expression was significantly higher in CAFs compared with OSCC tumor cells and normal fibroblasts. Higher FERMT2 expression might independently predict unfavorable disease-specific survival (DSS) in patients with OSCC. Knockdown of FERMT2 suppressed the expression and secretion of IGFBP7, SPARC, TIMP3, COL4A1, and IGFBP4 in OCAFs. OCAFs with FERMT2 knockdown had significantly weakened capability to induce the invasion of OSCC cells and the expression of mesenchymal markers. FERMT2 knockdown impaired the inducing effect of OCAFs on the migration of M0 macrophages and the expression of M2 macrophage markers.

CONCLUSIONS

FERMT2 could modulate the production and secretion of IGFBP7, SPARC, COL4A1, and IGFBP4 in OCAFs, thereby inducing the EMT of OSCC and M2 macrophage polarization.

Phytosulfokine promotes fruit ripening and quality via phosphorylation of transcription factor DREB2F in tomato

Phytosulfokine (PSK), a plant peptide hormone with a wide range of biological functions, is recognized by its receptor PHYTOSULFOKINE RECEPTOR 1 (PSKR1). Previous studies have reported that PSK plays important roles in plant growth, development, and stress responses. However, the involvement of PSK in fruit development and quality formation remains largely unknown. Here, using tomato (Solanum lycopersicum) as a research model, we show that exogenous application of PSK promotes the initiation of fruit ripening and quality formation, while these processes are delayed in pskr1 mutant fruits. Transcriptomic profiling revealed that molecular events and metabolic pathways associated with fruit ripening and quality formation are affected in pskr1 mutant lines and transcription factors are involved in PSKR1-mediated ripening. Yeast screening further identified that DEHYDRATION-RESPONSIVE ELEMENT BINDING PROTEIN 2F (DREB2F) interacts with PSKR1. Silencing of DREB2F delayed the initiation of fruit ripening and inhibited the promoting effect of PSK on fruit ripening. Moreover, the interaction between PSKR1 and DREB2F led to phosphorylation of DREB2F. PSK improved the efficiency of DREB2F phosphorylation by PSKR1 at the tyrosine-30 site, and the phosphorylation of this site increased the transcription level of potential target genes related to the ripening process and functioned in promoting fruit ripening and quality formation. These findings shed light on the involvement of PSK and its downstream signaling molecule DREB2F in controlling climacteric fruit ripening, offering insights into the regulatory mechanisms governing ripening processes in fleshy fruits.

Revealing the specific regulations of nitric oxide on the postharvest ripening and senescence of bitter melon fruit

Bitter melon fruit is susceptible to yellowing, softening, and rotting under room-temperature storage conditions, resulting in reduced commercial value. Nitric oxide (NO) is an important signaling molecule and plays a crucial role in regulating the fruit postharvest quality. In this study, we investigated the effects of NO treatment on changes in sensory and firmness of bitter melon fruit during postharvest storage. Moreover, transcriptomic, metabolomic, and proteomic analyses were performed to elucidate the regulatory mechanisms through which NO treatment delays the ripening and senescence of bitter melon fruit. Our results show that differentially expressed genes (DEGs) were involved in fruit texture (CSLE, β-Gal, and PME), plant hormone signal transduction (ACS, JAR4, and AUX28), and fruit flavor and aroma (SUS2, LOX, and GDH2). In addition, proteins differentially abundant were associated with fruit texture (PLY, PME, and PGA) and plant hormone signal transduction (PBL15, JAR1, and PYL9). Moreover, NO significantly increased the abundance of key enzymes involved in the phenylpropanoid biosynthetic pathway, thus enhancing the disease resistance and alleviating softening of bitter melon fruit. Finally, differential metabolites mainly included phenolic acids, terpenoids, and flavonoids. These results provide a theoretical basis for further studies on the physiological changes associated with postharvest ripening and senescence of bitter melon fruit.

Supplementary Information

The online version contains supplementary material available at 10.1007/s42994-023-00110-y.

Dissection of mRNA ac4C acetylation modifications in AC and Nr fruits: insights into the regulation of fruit ripening by ethylene

N4-acetylcytidine (ac4C) modification of mRNA has been shown to be present in plant RNAs, but its regulatory function in plant remains largely unexplored. In this study, we investigated the differentially expressed mRNAs, lncRNAs and acetylation modifications of mRNAs in tomato fruits from both genotypes. By comparing wild-type (AC) tomato and the ethylene receptor-mutant (Nr) tomato from mature green (MG) to six days after the breaker (Br6) stage, we identified differences in numerous key genes related to fruit ripening and observed the corresponding lncRNAs positively regulated the target genes expression. At the post-transcriptional level, the acetylation level decreased and increased in AC and Nr tomatoes from MG to Br6 stage, respectively. The integrated analysis of RNA-seq and ac4C-seq data revealed the potential positive role of acetylation modification in regulating gene expression. Furthermore, we found differential acetylation modifications of certain transcripts (ACO, ETR, ERF, PG, CesA, β-Gal, GAD, AMY, and SUS) in AC and Nr fruits which may explain the differences in ethylene production, fruit texture, and flavor during their ripening processes. The present study provides new insights into the molecular mechanisms by which acetylation modification differentially regulates the ripening process of wild-type and mutant tomato fruits deficient in ethylene signaling.

Multiomics analyses of the effects of LED white light on the ripening of apricot fruits

INTRODUCTION

Apricot (Prunus armeniaca L.) fruits are highly perishable and prone to quality deterioration during storage and transportation.

OBJECTIVES

To investigate the effects of LED white light treatment on postharvest ripening of fruits using metabolomics, transcriptomics, and ATAC-Seq analysis.

METHODS

Fruits were exposed to 5 μmol m-2 s-1 LED white light for 12 h followed by 12 h of darkness at 20 °C daily for 12 days. The effects of the treatments on the physiological and nutritional quality of the fruits were evaluated. These data were combined with transcriptomic, metabolomic, and ATAC-Seq data from fruits taken on 8 d of treatment to provide insight into the potential mechanism by which LED treatment delays ripening.

RESULTS

LED treatment activated pathways involved in ascorbate and aldarate metabolism and flavonoid and phenylpropanoid biosynthesis. Specifically, LED treatment increased the expression of UDP-sugar pyrophosphorylase (USP), L-ascorbate peroxidase (AO), dihydroflavonol 4-reductase (DFR), chalcone synthase (CHS), and caffeoyl-CoA O-methyltransferase (CCOAOMT1), leading to the accumulation of caffeoyl quinic acid, epigallocatechin, and dihydroquercetin and the activation of anthocyanin biosynthesis. LED treatment also affected the expression of genes associated with plant hormone signal transduction, fruit texture and color transformation, and antioxidant activity. The notable genes affected by LED treatment included 1-aminocyclopropane-1-carboxylate synthase (ACS), 1-aminocyclopropane-1-carboxylate oxidase (ACO), hexokinase (HK), lipoxygenase (LOX), malate dehydrogenase (MDH), endoglucanase (CEL), various transcription factors (TCP, MYB, EFR), and peroxidase (POD). ATAC-Seq analysis further revealed that LED treatment primarily regulated phenylpropanoid biosynthesis.

CONCLUSION

The results obtained in this study provide insights into the effects of LED light exposure on apricot fruits ripening. LEDs offer a promising approach for extending the shelf life of other fruits and vegetables.

Ozone micro-nano bubble water preserves the quality of postharvest parsley

The production and use of ozone micro-nano bubble water (O₃-MNBW) is an innovative technology that prolongs the reactivity of aqueous-phase ozone and maintains the freshness and quality of fruits and vegetables by removing pesticides, mycotoxins, and other contaminants. The quality of parsley treated with different concentrations of O₃-MNBW was investigated during storage at 20 ℃ for 5 d, and found that a ten-minute exposure of parsley to 2.5 mg·L^-1 O₃-MNBW effectively preserved the sensory quality of parsley, and resulted in lower weight loss, respiration rate, ethylene production, MDA levels, and a higher level of firmness, vitamin C, and chlorophyll content, relative to untreated parsley. The O₃-MNBW treatment also increased the level of total phenolics and flavonoids, enhanced peroxidase and ascorbate peroxidase activity, and inhibited polyphenol oxidase activity in stored parsley. Five volatile signatures identified using an electronic nose (W1W, sulfur-compounds; W2S, ethanol; W2W, aromatic- and organic- sulfur compounds; W5S, oxynitride; W1S, methane) exhibited a significant decrease in response to the O₃-MNBW treatment. A total of 24 major volatiles were identified. A metabolomic analysis identified 365 differentially abundant metabolites (DMs). Among them, 30 and 19 DMs were associated with characteristic volatile flavor substance metabolism in O₃-MNBW and control groups, respectively. The O₃-MNBW treatment increased the abundance of most DMs related to flavor metabolism and reduced the level of naringin and apigenin. Our results provide insight into the mechanisms that are regulated in response to the exposure of parsley to O₃-MNBW, and confirmed the potential use of O₃-MNBW as a preservation technology.

Whole-transcriptome RNA sequencing reveals changes in amino acid metabolism induced in harvested broccoli by red LED irradiation

Whole-transcriptomic profiling combined with amino acid analysis were conducted in order to gain a better understanding of global changes in amino acid metabolism induced in broccoli by red LED irradiation. The results showed that the contents of almost all 16 amino acids in postharvest broccoli were maintained under red LED illumination. The red LED irradiation enhanced the anabolism of amino acid, including the biosynthesis of aromatic amino acids by upregulating the genes' expression in the shikimate pathway, as well as by upregulating the genes' expression which encoding biosynthetic enzymes in the branched-chain amino acid biosynthesis pathway. Red LED irradiation induced the expression of genes encoding aspartate aminotransferase, which plays a role in Asp synthesis, aspartate kinase, which functions in aspartate metabolism, and a cytoplasmic aspartate aminotransferase that converts 2-Oxoglutarate into Glu. Genes encoding imidazole glycerol-phosphate synthase and histidinol-phosphatase, which function in the His biosynthesis pathway, were also upregulated. According to our results, red LED irradiation delays broccoli's yellowing and senescence by regulating amino acid metabolism. These results enhance our understanding of the role of amino acid metabolism in the senescence of broccoli and the mechanism of red LED irradiation to alter amino acid metabolism in harvested broccoli.

Effect of 100% Oxygen-Modified Atmosphere Packaging on Maintaining the Quality of Fresh-Cut Broccoli during Refrigerated Storage

The effect of 100% oxygen (O₂)-modified atmosphere packaging (MAP) on the quality improvement of fresh-cut broccoli stored at 4 °C for 15 days was investigated in this study. The results indicated that, compared to the control group conditions, 100% O₂ MAP treatment effectively maintained broccoli sensory evaluation scores, green color, and texture; reduced respiration and chlorophyll degradation; and reduced total bacterial count (TBC), malondialdehyde (MDA) levels, electrolyte leakage (EL), hydrogen peroxide (H₂O₂), and superoxide (O₂^-) contents. Furthermore, 100% O₂ MAP led to a smaller loss of nutrients and increased antioxidant capacity. In conclusion, the use of 100% O₂ MAP is an effective approach for maintaining high-quality fresh-cut broccoli during refrigerated storage at 4 °C.

The effect of BVOCs produced by Lysinibacillus fusiformis and LED irradiation on pigment metabolism in stored broccoli

Volatile organic compounds produced by bacteria (BVOCs) have been proven to effect the postharvest metabolism of fruits and vegetables. The quality, color and antioxidant capacity of membrane lipids of broccoli in storage were effectively maintained by fumigation with BVOCs produced by Lysinibacillus fusiformis combined with white light emitting diode (LED) technology. An analysis of the transcriptome and metabolome of broccoli treated with the combined LED-BVOCs technology resulted in the identification of 49 differentially expressed genes (DEGs) and 13 differentially abundant metabolites (DAMs) involved in photosynthesis (32/0 DEGs upregulated/downregulated; 0/0 DAMs with increased/decreased abundance), chlorophyll (7/0; 1/2), carotenoid (5/0; 1/4) and flavonoid (3/3; 3/2) metabolism. The maintenance of green color in harvested broccoli treated by LED-BVOCs was associated with DEGs and DAMs that inhibited chlorophyll degradation and carotenoid accumulation. Our study provides a theoretical basis for understanding the delayed senescence of broccoli during storage using BVOCs-LED technology.

Transcriptomic, metabolomic, and ATAC-seq analysis reveal the regulatory mechanism of senescence of post-harvest tomato fruit

Several physiological changes occur during fruit storage, which include the regulation of genes, metabolisms and transcription factors. In this study, we compared 'JF308' (a normal tomato cultivar) and 'YS006' (a storable tomato cultivar) to determine the difference in accumulated metabolites, gene expression, and accessible chromatin regions through metabolome, transcriptome, and ATAC-seq analysis. A total of 1006 metabolites were identified in two cultivars. During storage time, sugars, alcohols and flavonoids were found to be more abundant in 'YS006' compared to 'JF308' on day 7, 14, and 21, respectively. Differentially expressed genes, which involved in starch and sucrose biosynthesis were observed higher in 'YS006'. 'YS006' had lower expression levels of CesA (cellulose synthase), PL (pectate lyase), EXPA (expansin) and XTH (xyglucan endoglutransglucosylase/hydrolase) than 'JF308'. The results showed that phenylpropanoid pathway, carbohydrate metabolism and cell wall metabolism play important roles in prolonging the shelf life of tomato (Solanum lycopersicum) fruit. The ATAC-seq analysis revealed that the most significantly up-regulated transcription factors during storage were TCP 2,3,4,5, and 24 in 'YS006' compared to 'JF308' on day 21. This information on the molecular regulatory mechanisms and metabolic pathways of post-harvest quality changes in tomato fruit provides a theoretical foundation for slowing post-harvest decay and loss, and has theoretical importance and application value in breeding for longer shelf life cultivars.

[Research advances on the role and mechanism of microRNA in hypertrophic scar]

Hypertrophic scar (HS) affects the function and beauty of patients, and brings a heavy psychological burden to patients. However, the specific pathogenesis mechanism of HS in molecular biology level is not yet clear, and this disease is still one of the clinical diseases difficult to prevent and cure. MicroRNA (miR) is a family of single-stranded endogenous noncoding RNAs that can regulate gene expression. The abnormal transcription of miR in hypertrophic scar fibroblasts can affect the transduction and expression of downstream signal pathway or protein, and the exploration of miR and its downstream signal pathway and protein helps deeply understand the occurrence and development mechanism of scar hyperplasia. This article summarized and analyzed how miR and multiple signal pathways involve in the formation and development of HS in recent years, and further outlined the interaction between miR and target genes in HS.

Telomere-to-telomere genome assembly of bitter melon (Momordica charantia L. var. abbreviata Ser.) reveals fruit development, composition and ripening genetic characteristics

Momordica charantia L. var. abbreviata Ser. (Mca), known as bitter gourd or bitter melon, is a Momordica variety with medicinal value and belongs to the Cucurbitaceae family. In view of the lack of genomic information on bitter gourd and other Momordica species and to promote Mca genomic research, we assembled a 295.6-Mb telomere-to-telomere (T2T) high-quality Mca genome with six gap-free chromosomes after Hi-C correction. This genome is anchored to 11 chromosomes, which is consistent with the karyotype information, and comprises 98 contigs (N50 of 25.4 Mb) and 95 scaffolds (N50 of 25.4 Mb). The Mca genome harbors 19 895 protein-coding genes, of which 45.59% constitute predicted repeat sequences. Synteny analysis revealed variations involved in fruit quality during the divergence of bitter gourd. In addition, assay for transposase-accessible chromatin by high-throughput sequencing and metabolic analysis showed that momordicosides and other substances are characteristic of Mca fruit pulp. A combined transcriptomic and metabolomic analysis revealed the mechanisms of pigment accumulation and cucurbitacin biosynthesis in Mca fruit peels, providing fundamental molecular information for further research on Mca fruit ripening. This report provides a new genetic resource for Momordica genomic studies and contributes additional insights into Cucurbitaceae phylogeny.

Association of oxidative stress and Kashin-Beck disease integrated Meta and Bioinformatics analysis

OBJECTIVE

To explore the association between oxidative stress (OS) and Kashin-Beck disease (KBD).

METHODS

Terms associated with "KBD" and "OS" were searched in the six different databases up to October 2021. Stata 14.0 was used to pool the means and standard deviations using random-effect or fixed-effect model. The differentially expressed genes in the articular chondrocytes of KBD were identified, the OS related genes were identified by blasting with the GeneCards. The KEGG pathway and gene ontology enrichment analysis was conducted using STRING.

RESULTS

The pooled SMD and 95% CI showed hair selenium (-4.59; -6.99, -2.19), blood selenium (-1.65; -2.86, -0.44) and glutathione peroxidases (-4.15; -6.97, -1.33) levels were decreased in KBD, whereas the malondialdehyde (1.12; 0.60, 1.64), nitric oxide (2.29; 1.31, 3.27), nitric oxide synthase (1.07; 0.81, 1.33) and inducible nitric oxide synthase (1.69; 0.62, 2.77) were increased compared with external controls. Meanwhile, hair selenium (-2.71; -5.32, -0.10) and glutathione peroxidases (-1.00; -1.78, -0.22) in KBD were decreased, whereas the malondialdehyde (1.42; 1.04, 1.80), nitric oxide (3.08; 1.93, 4.22) and inducible nitric oxide synthase (0.81; 0.00, 1.61) were elevated compared with internal controls. Enrichment analysis revealed apoptosis was significantly correlated with KBD. The significant biological processes revealed OS induced the release of cytochrome c from mitochondria. The cellular component of OS located in the mitochondrial outer membrane.

CONCLUSIONS

The OS levels in KBD were significantly increased because of selenium deficiency, OS mainly occurred in mitochondrial outer membrane, released of cytochrome c from mitochondria, and induced apoptotic signaling pathway.

Transmission Line Sag Measurement and Simulation Research Based on Non-Contact Electric Field Sensing

Sag is an important indicator of the operational health of a transmission line, and its timely measurement is of great significance to maintain the stability and reliability of power systems. However, traditional contact measurements may be affected by the electromagnetic interference of conductors. In contrast, measurement methods without direct electrical contact with the subject provide greater portability and flexibility. This paper presents a study of a transmission line sag measurement and simulation based on non-contact electric field sensing. The finite element method was used to analyze the conductor distribution, establish the coupling relationships among the electric field, transmission line, and measurement point, propose a sag inverse calculation model, and assess the impact of the transmission line parameter on the curved drooping measurement. Simultaneously, sag measurement schemes for single-round and dual-circuit lines were designed for multi-conductive lines, and measurement array studies were conducted. The vertical component of the electric field in space measured by the array was obtained, which could be used to perform conductor sag measurement simply and efficiently. The proposed method will facilitate the monitoring of the overhead transmission line status, which is conducive to the effective operation of the entire system.

Effects of methyl salicylate pre-treatment on the volatile profiles and key gene expressions in tomatoes stored at low temperature

Tomato is one of the most widely cultivated horticultural plants in the world, while the key volatile compounds of tomato fruits generally derive from fatty acid, carotenoid, phenylalanine, and branched-chain amino acid pathways. As an important endogenous signal molecule, methyl salicylate (MeSA) plays a crucial role in the fruit ripening process of plant. Recently, it has been demonstrated that MeSA can maintain the flavor quality of full ripe tomatoes after cold-storage preservation. However, few research teams attempted to investigate the effects of MeSA plus low temperature treatment on the different volatile biosynthetic pathways of tomatoes previously. Therefore, in this study, the effects of methyl salicylate pre-treatment (0.05 mM MeSA, 24 h) on the volatile profile and flavor-related key gene expressions of tomato fruits stored at 10°C were evaluated for the first time. Our results showed that the loss of volatile compounds in low temperature-treated tomato fruits could be effectively alleviated by MeSA pre-treatment. Although MeSA had no remarkable effect on the formation of carotenoid pathway- and branched-chain amino acid pathway-related volatiles in tomatoes subjected to low temperature, the content of fatty acid pathway-related volatiles (including cis-3-hexenal, hexanal, and trans-2-hexenal) in full red fruits of 10°C MeSA group was remarkably higher than that of 10°C control group. Furthermore, MeSA pre-treatment significantly up-regulated the expression of LOXC or LOXD gene in low temperature-treated fruits at breaker or full red stage, respectively. In conclusion, pre-treatment with MeSA might avoid the loss of aromatic compounds in tomato fruits stored at low temperature by activating the fatty acid pathway.

DNA and coding/non-coding RNA methylation analysis provide insights into tomato fruit ripening

Ripening is the last, irreversible developmental stage during which fruit become palatable, thus promoting seed dispersal by frugivory. In Alisa Craig fruit, mRNAs with increasing m5C levels, such as STPK and WRKY 40, were identified as being involved in response to biotic and abiotic stresses. Furthermore, two mRNAs involved in cell wall metabolism, PG and EXP-B1, also presented increased m5C levels. In the Nr mutant, several m5C-modified mRNAs involved in fruit ripening, including those encoding WRKY and MADS-box proteins, were found. Targets of long non-coding RNAs and circular RNAs with different m5C sites were also found; these targets included 2-alkenal reductase, soluble starch synthase 1, WRKY, MADS-box, and F-box/ketch-repeat protein SKIP11. A combined analysis of changes in 5mC methylation and mRNA revealed many differentially expressed genes with differentially methylated regions encoding transcription factors and key enzymes related to ethylene biosynthesis and signal transduction; these included ERF084, EIN3, AP2/ERF, ACO5, ACS7, EIN3/4, EBF1, MADS-box, AP2/ERF, and ETR1. Taken together, our findings contribute to the global understanding of the mechanisms underlying fruit ripening, thereby providing new information for both fruit and post-harvest behavior.

The role and interaction between transcription factor NAC-NOR and DNA demethylase SlDML2 in the biosynthesis of tomato fruit flavor volatiles

Flavor-imparting volatile chemicals accumulate as fruits ripen, making major contributions to taste. The NAC transcription factor nonripening (NAC-NOR) and DNA demethylase 2 (SlDML2) are essential for tomato fruit ripening, but details of the potential roles and the relationship between these two regulators in the synthesis of volatiles are lacking. Here, we show substantial reductions in fatty acid and carotenoid-derived volatiles in tomato slnor and sldml2 mutants. An unexpected finding is the redundancy and divergence in volatile profiles, biosynthetic gene expression, and DNA methylation in slnor and sldml2 mutants relative to wild-type tomato fruit. Reduced transcript levels are accompanied by hypermethylation of promoters, including the NAC-NOR target gene lipoxygenase (SlLOXC) that is involved in fatty acid-derived volatile synthesis. Interestingly, NAC-NOR activates SlDML2 expression by directly binding to its promoter both in vitro and in vivo. Meanwhile, reduced NAC-NOR expression in the sldml2 mutant is accompanied by hypermethylation of its promoter. These results reveal a relationship between SlDML2-mediated DNA demethylation and NAC-NOR during tomato fruit ripening. In addition to providing new insights into the metabolic modulation of flavor volatiles, the outcome of our study contributes to understanding the genetics and control of fruit ripening and quality attributes in tomato.

The SARS-CoV-2 rS1-E-PLGA nanovaccine and evaluation of its immune effect in BALB/c mice

OBJECTIVE

Vaccination is an important method for preventing COVID-19 infection. However, certain vaccines do not meet the current needs. To improve the vaccine effect, discard ineffective antigens, and focus on high-quality antigenic clusters, S1-E bivalent antigens were designed.

MATERIALS AND METHODS

Vaccine delivery is performed using poly (lactic-co-glycolic acid) (PLGA). Here, the recombinant S1-E (rS1-E) was covered on PLGA and injected intramuscularly into mice. In total, 48 BALB/c mice were randomly divided into six groups with 8 mice in each group. The mice received intramuscular injections. Prior to vaccination, the hydrophobicity of the rS1-E and the antigenic site of the E protein were both analysed. The morphology, zeta potential, and particle size distribution of rS1-E-PLGA were examined. Anti-S1 and anti-E antibodies were detected in mouse serum by ELISA. Neutralising an-tibodies were detected by co-incubating the pseudovirus with the obtained serum. IL-2 and TNF-α levels were also measured.

RESULTS

The designed recombinant S1-E protein was successfully coated on PLGA nanoparticles. rS1-E-PLGA nanovaccine has suitable size, shape, good stability, sustained release and other characteristics. Importantly, mice were stimulated with rS1-E-PLGA nanovaccines to produce high-titre antibodies and a good cellular immune response.

CONCLUSIONS

Our results indicate that rS1-E-PLGA nanovaccine may provide a good protective effect, and the vaccine should be further investigated in human clinical trials for use in vaccination or as a booster.

The Microbial Metagenome of Eluates Obtained From the Surface of Broccoli Heads Subjected to Different Light Treatments

Foodborne illnesses present a major threat to public health and are frequently attributed to foodborne pathogens present on fresh produce. Some opportunistic pathogens of broccoli are also responsible for causing head rot. Three different light treatments, UV-C, red LED (50 μml/m²/s), and UV-C + LED were used to treat broccoli prior to or during storage. Following the light treatments, microorganisms present in eluates obtained from the surface of broccoli heads were characterized using a metagenomic approach. Metagenomic DNA libraries were subjected to high-throughput sequencing on an Illumina Hiseq platform. Results indicated that the combined treatment of LED red light and UV-C provided the best sensory preservation of broccoli, followed by LED red light and then UV-C. The bacterial communities in the eluates obtained from the surface of broccoli heads in all three light treatments were primarily represented at the phylum level by Proteobacteria and Firmicutes, while fungal communities were primarily represented by Ascomycota and Basidiomycota. Further analysis indicated that the all three light treatments reduced the presence of foodborne pathogens and bacterial taxa responsible for broccoli spoilage. While UV-C had a significant inhibitory effect on Botrytis cinerea, the light treatments increased the relative abundance of Pseudomonas fluorescens. Results indicate that a metagenomic approach can be used to detect pathogenic bacteria and fungi on fresh vegetables and assess the impact of management practices, such as light treatments, designed to maintain postharvest quality, on the composition of the microbiome present on the surface of harvested produce.

Cucurbitaceae genome evolution, gene function and molecular breeding

The Cucurbitaceae is one of the most genetically diverse plant families in the world. Many of them are important vegetables or medicinal plants and are widely distributed worldwide. The rapid development of sequencing technologies and bioinformatic algorithms has enabled the generation of genome sequences of numerous important Cucurbitaceae species. This has greatly facilitated research on gene identification, genome evolution, genetic variation and molecular breeding of cucurbit crops. So far, genome sequences of 18 different cucurbit species belonging to tribes Benincaseae, Cucurbiteae, Sicyoeae, Momordiceae and Siraitieae have been deciphered. This review summarizes the genome sequence information, evolutionary relationship, and functional genes associated with important agronomic traits (e.g., fruit quality). The progress of molecular breeding in cucurbit crops and prospects for future applications of Cucurbitaceae genome information are also discussed.

The Burden of Colorectal Cancer Attributable to Diet Low in Fiber from 1990 to 2019: A Global, Regional and National Analysis

OBJECTIVES

The colorectal cancer (CRC) burden is increasingly high. The aim of this study was to investigate temporal and geographical trends in CRC deaths and disability-adjusted life-years (DALYs) attributable to diet low in fiber globally from 1990 to 2019.

DESIGN

Cross-sectional study.

SETTING

The study based on the Global Burden of Disease Study (GBD) 2019.

PARTICIPANTS

The population comprised individuals from 204 countries and territories who were diagnosed with CRC attributable to diet low in fiber from 1990 to 2019.

MEASUREMENTS

Deaths, DALYs, age-standardized mortality rates (ASMR), and age-standardized DALY rates (ASDR) for CRC attributable to diet low in fiber were described, and estimated annual percentage change (EAPC) was further calculated to assess the burden in different regions, countries, sexes, and age groups. Additionally, we explored the association between EAPC and ASMR/ASDR (in 1990) and Human Development Index (HDI, in 2019).

RESULTS

From 1990 to 2019, global ASMR and ASDR for CRC attributable to diet low in fiber decreased slightly, but the corresponding deaths and DALYs increased by 63.37% and 51.36%, respectively. Those burden varied considerably between regions and countries. The burden was higher in high, high-middle and middle SDI regions, especially in Asia and Western Europe, but when HDI > 0.7, an increasingly rapid decline in ASMR and ASDR was revealed. Unexpectedly, many less well-developed countries within the traditionally low deaths and DALYs regions of Africa, Central Latin America, and Middle East showed gradual increases in ASMR and ASDR.

CONCLUSION

The global burden of CRC attributable to diet low in fiber has decreased over the last 30 years, but remains at a high level. It is essential for decision-makers to take targeted measures for improving population awareness and intake of dietary fiber.

Revealing the Specific Regulations of Brassinolide on Tomato Fruit Chilling Injury by Integrated Multi-Omics

Tomato fruit is susceptible to chilling injury (CI) when stored at low temperatures, limiting its storage potential, and resulting in economic loss if inappropriate temperatures are used. Brassinolide (BR) is a plant growth regulator that is known to decrease the susceptibility of fruit to CI. In this study, transcriptome, metabolome, and proteome analysis revealed the regulation mechanism of BR treatment in alleviating tomato fruit CI. The results showed that the differentially expressed metabolites mainly included amino acids, organic acids, carbohydrates, and lipids. Differentially expressed genes (DEGs) were involved in plant cold stress response (HSFA3, SHSP, and TPR), fruit redox process (POD, PAL, and LOX), related to the fruit texture (CESA, β-Gal, and PAE), plant hormone signal transduction (ACS3, ARF, and ERF,), transcription factors (TCP, bHLH, GATA). Moreover, differentially expressed proteins were associated with fruit texture (CESA, PE, PL, and CHI), plant oxidation processes (LOX, GPX, CAT, and POD), plant cold stress response (HSF, HSP20, HSP70, and HSP90B), plant hormone signal transduction (BSK1 and JAR1) and transcription factors (WRKY and MYB). Our study showed that BR alleviates CI symptoms of tomato fruit by regulating LOX in the α-linolenic acid metabolism pathway, enhancing jasmonic acid-CoA (JA-CoA) synthesis, inhibiting cell wall and membrane lipid damage. The results provided a theoretical basis for further study on the CI mechanism of tomato fruit.

[Identification of serum peptide biomarker for ovarian cancer diagnosis by Clin-TOF-II-MS combined with magnetic beads technology]

Objective: To explore the serum cyclic polypeptide biomarkers for ovarian cancer diagnosis. Methods: A total of 54 patients with epithelial ovarian cancer confirmed by pathology in Cancer Hospital, Chinese Academy of Medical Sciences from March 2018 to September 2018 were selected as the study subjects, and 40 healthy women with normal examination results in the cancer screening center were selected as the control. All of the samples were randomly divided into training set and validation set at the ratio of 1∶1 with a random number. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) combined with magnetic bead technology was used for detecting peptide profiling in serum samples to screen significantly differently expressed peptides between ovarian cancer group and control group of the training set (score>5). Receiver operating characteristic (ROC) curve analysis was used to screen differential peptide peaks with area under curve (AUC) ≥0.8, sensitivity and specificity>90% in the training set and validation set. Liquid chromatography-mass spectrometry (LC-MS/MS) was further used to determine the composition of differentially expressed peptides. Results: By comparing the peptide profiles of the two groups, 102 differential peptide peaks were initially detected in the mass-to-charge ratio range of 1 000 to 10 000. ROC curve analysis showed that there were 42 differential peptide peaks with AUC ≥0.8 in both training set and validation set, 19 of which were highly expressed in ovarian cancer group, and 23 were lowly expressed. There were 15 different peptide peaks in highly expressed ovarian cancer group with sensitivity and specificity over 90%. The mass-to-charge ratios were 7 744.27, 5 913.41, 5 329.87, 4 634.21, 4 202.02, 3 879.26, 3 273.35, 3 253.79, 3 234.34, 2 950.33, 2 664.51, 2 018.38, 1 893.37, 1 498.69 and 1 287.55. There were 15 different peptide peaks in lowly expressed ovarian cancer group with sensitivity and specificity over 90%, the mass-to-charge ratios were 9 288.46, 7 759.77, 5 925.24, 4 652.77, 4 210.42, 3 887.02, 3 279.90, 3 240.82, 2 962.15, 2 932.70, 2 022.42, 1 897.16, 1 501.69, 1 337.38 and 1 290.13. No protein composition was identified in 15 different peptide peaks in lowly expressed ovarian cancer group. The two protein compositions identified in 15 different peptide peaks in highly expressed ovarian cancer group were recombinant serglycin (SRGN) and fibinogen alpha chain (FGA), the mass-to-charge ratios of which were 1 498.696 and 5 913.417, respectively. The sensitivity and specificity of the two proteins for ovarian cancer diagnosis were 100%, 100% and 90.9%, 100%, respectively. Conclusion: SRGN and FGA are highly expressed in the serum of ovarian cancer patients, which may be potential diagnostic markers for ovarian cancer.

Antibody responses after first and second Covid-19 vaccination in patients with chronic lymphocytic leukaemia

B-cell chronic lymphocytic leukaemia (CLL) is associated with immunosuppression and patients are at increased clinical risk following SARS-CoV-2 infection. Covid-19 vaccines offer the potential for protection against severe infection but relatively little is known regarding the profile of the antibody response following first or second vaccination. We studied spike-specific antibody responses following first and/or second Covid-19 vaccination in 299 patients with CLL compared with healthy donors. 286 patients underwent extended interval (10-12 week) vaccination. 154 patients received the BNT162b2 mRNA vaccine and 145 patients received ChAdOx1. Blood samples were taken either by venepuncture or as dried blood spots on filter paper. Spike-specific antibody responses were detectable in 34% of patients with CLL after one vaccine (n = 267) compared to 94% in healthy donors with antibody titres 104-fold lower in the patient group. Antibody responses increased to 75% after second vaccine (n = 55), compared to 100% in healthy donors, although titres remained lower. Multivariate analysis showed that current treatment with BTK inhibitors or IgA deficiency were independently associated with failure to generate an antibody response after the second vaccine. This work supports the need for optimisation of vaccination strategy in patients with CLL including the potential utility of booster vaccines.

[Analysis of PARP inhibitors induced anemia in advanced and relapsed epithelial ovarian cancer]

Objective: To explore the clinical features of poly ADP-ribose polymerase (PARP) inhibitor-related anemia in advanced and relapsed epithelial ovarian cancer (EOC). Methods: Patients diagnosed with advanced or relapsed EOC and treated with PARP inhibitor at National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College between January 2015 to October 2020 were accrued. The data included PARP inhibitors, treatment details, and lab tests before treatment and during treatment were collected and the clinical characteristics of PARP inhibitor-related anemia were analyzed. Results: (1) A total of 98 patients with a median age of 56.5 years old (30-82 years old) were enrolled in this study. All patients were treated with PARP inhibitor (65 cases of olaparib, 17 cases of niraparib, and 16 cases of fluzoparib). The median treatment duration was 37.5 weeks (4-119 weeks). (2) The anemia rate was 40% (39/98), including 5% (5/98) of grade Ⅰ, 14% (14/98) of grade Ⅱ, 11% (11/98) of grade Ⅲ, and 9% (9/98) of grade Ⅳ. Fourteen patients with pre-treatment grade Ⅰ anemia had a higher rate of anemia events than the 80 patients without pre-treatment anemia, 7/14 vs 35% (28/80; χ²=4.281, P=0.039). (3) The median anemia occurrence time was 7.0 weeks (1-52 weeks), including 41% (16/39) of anemia cases occurred in 1-4 weeks, 26% (10/39) occurred in 5-8 weeks, 13% (5/39) occurred in 9-12 weeks, 3% (1/39) occurred in 13-16 weeks, 10% (4/39) occurred in 17-20 weeks, 8% (3/39) occurred ≥21 weeks. At the time of the lowest hemoglobulin tested, the median value of mean corpuscular volume (MCV) was 106 fl,which was higher than the up limit of normal range (100 fl), 74% (29/39) of anemia patients had an elevated MCV level; the median value of mean corpuscular hemoglobin (MCH) was 36 pg, 54% (21/39) of anemia patients had an elevated MCH level; the median value of mean corpuscular hemoglobin concentration (MCHC) was 320 g/L, 69% (27/39) of anemia patients had a higher MCHC level; 92% (36/39) of anemia patients had a normal level of serum iron; 79% (31/39) of anemia patients had a normal level of transferrin. 74% (29/39) of the anemia patients were macrocytic orthochromatic anemia. (4) Among the 39 patients with anemia, 20 patients (51%, 20/39) withhold the treatment of PARP inhibitor due to grade Ⅲ or Ⅳ anemia, including 10 patients (50%, 10/20) who resumed the PARP inhibitor treatment by suppling iron, folate, and vitamin B₁₂. The median stopping time of PARP inhibitor was 5.5 weeks (2-10 weeks), while the other 10 patients terminated the PARP inhibitor treatment for not recovering from severe anemia. Conclusions: One of the common adverse effects of PARP inhibitors is anemia, which mostly happened in the first 3 months of treatment. In the treatment of EOC, PARP inhibitor-related anemia mainly manifest as macrocytic orthochromatic anemia, and most patients with normal serum iron and transferrin.

CircRNA HIPK3 promotes the progression of oral squamous cell carcinoma through upregulation of the NUPR1/PI3K/AKT pathway by sponging miR-637

Background

To investigate the expression, function, and related mechanisms of circHIPK3 in oral squamous cell carcinoma (OSCC).

Methods

CircHIPK3 expression was determined by quantitative reverse transcription polymerized chain reaction (QRT-PCR) in OSCC and adjacent tissues, and the correlation between the circHIPK3 level and clinicopathological indexes of OSCC was analyzed. CircHIPK3 expressions in different OSCC cell lines were detected, cell counting kit-8 (CCK-8) and 5-bromodeoxyuridine (BrdU) assays were utilized to monitor cell proliferation and activity. Flow cytometry was adopted to detect apoptosis and transwell assay was used to detect cell invasion. The expressions of nuclear protein 1 (NUPR1), phosphatidylinositol 3 kinase (PI3K)/protein kinase B (AKT) (PI3K/AKT) pathway proteins, and E-cadherin, Vimentin, and N-cadherin markers of epithelial-mesenchymal transformation (EMT) were detected by Western blot or Quantitative Real-time PCR (QRT-PCR).

Results

Upregulated circHIPK3 was noted in OSCC tissues (compared with adjacent tissues), and its overexpression was related to OSCC size and histopathological grade. Functionally, overexpressed circHIPK3 can significantly promote EMT, proliferation, and invasion of OSCC cells and can inhibit cell apoptosis in vivo and in vitro. In addition, CircHIPK3 upregulated the activation of NUPR1 and PI3K/AKT. Bioinformatics analyses showed that miR-637 was the common target of circHIPK3 and NUPR1, while a dual luciferase reporting assay and RIP assay further demonstrated that circHIPK3 targeted miR-637 and bound to 3' UTR of NUPR1.

Conclusions

CircHIPK3 demonstrates potential as a prognostic marker of OSCC and mediates OSCC progression via the miR-637-mediated NUPR1/PI3K/AKT axis.

High CO2 - and pathogen-driven expression of the carbonic anhydrase βCA3 confers basal immunity in tomato

Atmospheric CO₂ concentrations exert a strong influence on the susceptibility of plants to pathogens. However, the mechanisms involved in the CO₂ -dependent regulation of pathogen resistance are largely unknown. Here we show that the expression of tomato (Solanum lycopersicum) β-CARBONIC ANHYDRASE 3 (βCA3) is induced by the virulent pathogen Pseudomonas syringae pv. tomato DC3000. The role of βCA3 in the high CO₂ -mediated response in tomato and two other Solanaceae crops is distinct from that in Arabidopsis thaliana. Using βCA3 knock-out and over-expression plants, we demonstrate that βCA3 plays a positive role in the activation of basal immunity, particularly under high CO₂ . βCA3 is transcriptionally activated by the transcription factor NAC43 and is also post-translationally regulated by the receptor-like kinase GRACE1. The βCA3 pathway of basal immunity is independent on stomatal- and salicylic-acid-dependent regulation. Global transcriptome analysis and cell wall metabolite measurement implicate cell wall metabolism/integrity in βCA3-mediated basal immunity under both CO₂ conditions. These data not only highlight the importance of βCA3 in plant basal immunity under high CO₂ in a well-studied susceptible crop-pathogen system, but they also point to new targets for disease management strategies in a changing climate.

Combined genomic, transcriptomic, and metabolomic analyses provide insights into chayote (Sechium edule) evolution and fruit development

Chayote (Sechium edule) is an agricultural crop in the Cucurbitaceae family that is rich in bioactive components. To enhance genetic research on chayote, we used Nanopore third-generation sequencing combined with Hi-C data to assemble a draft chayote genome. A chromosome-level assembly anchored on 14 chromosomes (N50 contig and scaffold sizes of 8.40 and 46.56 Mb, respectively) estimated the genome size as 606.42 Mb, which is large for the Cucurbitaceae, with 65.94% (401.08 Mb) of the genome comprising repetitive sequences; 28,237 protein-coding genes were predicted. Comparative genome analysis indicated that chayote and snake gourd diverged from sponge gourd and that a whole-genome duplication (WGD) event occurred in chayote at 25 ± 4 Mya. Transcriptional and metabolic analysis revealed genes involved in fruit texture, pigment, flavor, flavonoids, antioxidants, and plant hormones during chayote fruit development. The analysis of the genome, transcriptome, and metabolome provides insights into chayote evolution and lays the groundwork for future research on fruit and tuber development and genetic improvements in chayote.

Maintenance treatment in advanced HER2-negative gastric cancer

Survival for patients with advanced gastric cancer (GC) remains poor. Systemic chemotherapy which has reached a plateau stays the standard first-line (1L) treatment for advanced human epidermal growth-factor receptor 2 (HER2)-negative GC. To maximize the benefit of 1L treatment, the concept of maintenance treatment is constantly being explored. In advanced HER2-negative GC, current clinical guidelines do not recommend a standard maintenance therapy strategy. In addition to the monotherapy maintenance with fluorouracil after 4-6 cycles of 1L chemotherapy, some agents that are active against novel targets have been evaluated in clinical trials for maintenance treatment. Whereas most of these trials do not reach their primary endpoints, they open new horizons for the 1L treatment of advanced HER2-negative GC. Therefore, we reviewed the clinical trials in the field of maintenance treatment in advanced HER2-negative GC and discussed some of the problems in clinical trials.

The genome and transcriptome analysis of snake gourd provide insights into its evolution and fruit development and ripening

Snake gourd (Trichosanthes anguina L.), which belongs to the Cucurbitaceae family, is a popular ornamental and food crop species with medicinal value and is grown in many parts of the world. Although progress has been made in its genetic improvement, the organization, composition, and evolution of the snake gourd genome remain largely unknown. Here, we report a high-quality genome assembly for snake gourd, comprising 202 contigs, with a total size of 919.8 Mb and an N50 size of 20.1 Mb. These findings indicate that snake gourd has one of the largest genomes of Cucurbitaceae species sequenced to date. The snake gourd genome assembly harbors 22,874 protein-coding genes and 80.0% of the genome consists of repetitive sequences. Phylogenetic analysis reveals that snake gourd is closely related to sponge gourd but diverged from their common ancestor ~33-47 million years ago. The genome sequence reported here serves as a valuable resource for snake gourd genetic research and comparative genomic studies in Cucurbitaceae and other plant species. In addition, fruit transcriptome analysis reveals the candidate genes related to quality traits during snake gourd fruit development and provides a basis for future research on snake gourd fruit development and ripening at the transcript level.

The split-off terahertz radiating dipoles on thermally reduced α-V2O5 (001) surface

The trapped electron states on a pliable lattice have different localization and physical chemistry characteristics. Here, terahertz time-domain measurements suggest that the formation of vanadyl oxygen defect, in the presence of the surface potential traps and mobile charge carriers, leads to a transient charge distribution that forms terahertz radiating dipoles in V2O5. The emergence of radiating dipoles is evidenced by terahertz responses with a two-valley feature of the thermally reduced α-V2O5 (001) thin films in the temperature range of 300-700 K. The two photoconductance valleys on a several millielectron volts interval are related to two emergent split-off traps, which originate from the VO6 octahedra distortion upon the vanadyl oxygen desorption on the surface. The pliable surface lattices plays a decisive role. So long as the α-V2O5 (001) thin films are covered by a 30 nm-thick Al2O3 capping layer, the distinct two-valley feature disappears completely in the full temperature range. The terahertz radiating dipoles with a fine energy structure is potentially a new measure for charge dynamics on the α-V2O5 (001) surface.

Effect of folic acid on the postharvest physiology of broccoli during storage

The objective of the present study was to explore the effect of folic acid on the postharvest physiology of broccoli placed in storage. Broccoli heads were immersed in 5 mg L^-1 folic acid for 10 min, then stored at 20 ± 1 °C for 4 days. Results indicated that the postharvest treatment of broccoli with folic acid decreased the rate of flower opening and yellowing, inhibited weight loss, reduced the level of respiration, as well as ethylene generation. Folic acid-treated broccoli maintained their level of chlorophyll, total soluble solids, vitamin C, total phenolics, flavonoids, glucosinolate, and folic acid. Treated broccoli also exhibited reduced accumulation of malondialdehyde (MDA) and reactive oxygen species (ROS). Concomitantly, antioxidant enzyme activity and corresponding gene expression were also enhanced. In contrast, chlorophyll-degrading enzyme gene expression was suppressed. These results indicated that folic acid treatment of broccoli could be used to prolong shelf-life.

Relationships between genome methylation, levels of non-coding RNAs, mRNAs and metabolites in ripening tomato fruit

Ripening of tomato fruit is a complex tightly orchestrated developmental process that involves multiple physiological and metabolic changes that render fruit attractive, palatable and nutritious. Ripening requires initiation, activation and coordination of key pathways at the transcriptional and post-transcriptional levels that lead to ethylene synthesis and downstream ripening events determining quality. We studied wild-type, Gr and r mutant fruits at the coding and non-coding transcriptomic, metabolomic and genome methylation levels. Numerous differentially expressed non-coding RNAs were identified and quantified and potential competing endogenous RNA regulation models were constructed. Multiple changes in gene methylation were linked to the ethylene pathway and ripening processes. A combined analysis of changes in genome methylation, long non-coding RNAs, circular RNAs, micro-RNAs and fruit metabolites revealed many differentially expressed genes (DEGs) with differentially methylated regions encoding transcription factors and key enzymes related to ethylene or carotenoid pathways potentially targeted by differentially expressed non-coding RNAs. These included ACO2 (targeted by MSTRG.59396.1 and miR396b), CTR1 (targeted by MSTRG.43594.1 and miR171b), ERF2 (targeted by MSTRG.183681.1), ERF5 (targeted by miR9470-3p), PSY1 (targeted by MSTRG.95226.7), ZISO (targeted by 12:66127788|66128276) and NCED (targeted by MSTRG.181568.2). Understanding the functioning of this intricate genetic regulatory network provides new insights into the underlying integration and relationships between the multiple events that collectively determine the ripe phenotype.

BCCIPβ facilitates p53 ubiquitination via binding with E6 protein in high-risk HPV positive head and neck squamous cell carcinoma

BRCA2 And CDKN1A Interacting Protein (BCCIP) is initially identified as a tumor suppressor. Some recent studies confirmed its p53 binding capability. In this study, we explored the regulatory effect of BCCIPβ on p53 stability in HPV-positive and HPV-negative HNSCC cells. RNA-seq data from TCGA-HNSC were extracted for transcript isoform analysis in HPV-positive and HPV-negative tumors. HPV16-positive UM-SCC-47 (SCC47) and UM-SCC-104 (SCC104) and HPV-negative SCC-9 (SCC9) and UM-SCC-1 (SCC1) cell lines were used as in vitro cell models. Results showed that BCCIPβ was the dominant transcript in both HPV-positive and HPV-negative HNSCC cases. Knockdown of BCCIPβ decreased p53 protein concentration in the two HPV-negative cell lines but increased p53 concentration in the two HPV-positive cell lines. BCCIPβ inhibition increased proliferation and G1/S transition of SCC9 and SCC1 cells. In comparison, BCCIPβ inhibition slowed proliferation and increased G1 arrest of SCC104 and SCC47 cells. BCCIPβ inhibition prolonged the half-life of p53 protein and reduced p53 ubiquitination in the two HPV16-positive cell lines. Co-IP assay confirmed interactions among BCCIPβ, HPV E6, and p53 in both SCC104 and SCC47 cells. In comparison, only the interaction between BCCIPα and p53 was confirmed in these two cell lines. Either E6 or BCCIPβ inhibition reduced p53 ubiquitination and increased p53 concentration. However, inhibiting E6 and BCCIPβ at the same did not generate synergistic effects. On the contrary, p53 ubiquitination level was even higher in the combination group, with lower p53 concentration compared to the shE6 group. BCCIPβ overexpression in SCC47 cells with HPV E6 depletion significantly reduced p53 ubiquitination. In conclusion, this study found a novel interaction between HPV E6 and BCCIPβ in HPV16-positive HNSCC cells. The presence of HPV E6 turned BCCIPβ from a p53 stabilizer to a ubiquitination facilitator. This mechanism helps explain why BCCIPβ acted as a tumor suppressor in HPV-negative HNSCC but exerted oncogenic function in HPV16-positive HNSCC.

Intravitreal conbercept for branch retinal vein occlusion induced macular edema: one initial injection versus three monthly injections

Background

To compare the efficacy of one initial intravitreal injection of conbercept (IVC) versus three monthly IVCs in patients with macular edema (ME) after branch retinal vein occlusion (BRVO). Both options were followed by a pro re nata (PRN) retreatment regimen.

Methods

This study retrospectively investigated and followed 60 patients with acute ME secondary to BRVO for over a year. 30 subjects received one initial injection (1 + PRN group); while, 30 received three monthly injections (3 + PRN group). The functional and anatomic outcomes were assessed during each follow-up.

Results

The general characteristics of the 60 subjects were as follows: mean [SD] age, 57.43 [13.06] years; 33 [55%] female; 36 [60%] non-ischemic form. Both groups showed a stable gain in visual acuity (VA) with similar logMAR (mean ± SD) (1 + PRN group 0.308 ± 0.399, 3 + PRN group 0.34 ± 0.352) during the first 12 months. Additionally, both groups exhibited a significant reduction in central foveal thickness (CFT) with no statistically significant difference between them (1 + PRN group 222.1 μm ± 197.1 μm, 3 + PRN group 228.4 μm ± 200.2 μm). Both treatment groups had similar improvements in logMAR and anatomic outcomes over time. The stratified analysis showed that patients with the non-ischemic form and those with the ischemic form had similar improvements in VA (0.346 ± 0.366 VS 0.29 ± 0.39, P = 0.575) during the 12 months follow-ups. The number of injections was lower in the 1 + PRN group (4.0 ± 1.6) than in the 3 + PRN group (4.7 ± 1.3) (P = 0.068). No adverse effects or unexpected safety issues were reported in either group.

Conclusions

Conbercept yielded significant improvements in VA and CFT among patients with BRVO induced ME, independent of their retinal ischemia status. The results showed that the 3 + PRN regimen do not lead to better functional outcomes or lower treatment needs in clinical practice as compared to the 1 + PRN regimen.

Noncoding RNAs: functional regulatory factors in tomato fruit ripening

Tomato has emerged as the model system for investigations into the regulation of fleshy-fruit ripening and senescence, and the ripening process involving the coordinated regulation at the gene/chromatin/epigenetic, transcriptional, post-transcriptional and protein levels. Noncoding RNAs play important roles in fruit ripening as important transcriptional and post-transcriptional regulatory factors. In this review, we systematically summarize the recent advances in the regulation of tomato fruit ripening involved in ethylene biosynthesis and signal transduction, fruit pigment accumulation, fruit flavor and aroma, fruit texture by noncoding RNAs and their coordinate regulatory network model were set up and also suggest future directions for the functional regulations of noncoding RNAs on tomato fruit ripening.

Integrated Analysis of Transcriptomic and Metabolomic Data Reveals the Mechanism by Which LED Light Irradiation Extends the Postharvest Quality of Pak-choi (Brassica campestris L. ssp. chinensis (L.) Makino var. communis Tsen et Lee)

Low-intensity (10 μmol m-2 s-1) white LED (light-emitting diode) light effectively delayed senescence and maintained the quality of postharvest pakchoi during storage at 20 °C. To investigate the mechanism of LED treatment in maintaining the quality of pakchoi, metabolite profiles reported previously were complemented by transcriptomic profiling to provide greater information. A total of 7761 differentially expressed genes (DEGs) were identified in response to the LED irradiation of pak-choi during postharvest storage. Several pathways were markedly induced by LED irradiation, with photosynthesis being the most notable. More specifically, porphyrin and chlorophyll metabolism and glucosinolate biosynthesis were significantly induced by LED irradiation, which is consistent with metabolomics reported previously. Additionally, chlorophyllide a, chlorophyll, as well as total glucosinolate content was positively induced by LED irradiation. Overall, LED irradiation delayed the senescence of postharvest pak-choi mainly by activating photosynthesis, inducting glucosinolate biosynthesis, and inhibiting the down-regulation of porphyrin and chlorophyll metabolism pathways. The present study provides new insights into the effect and the underlying mechanism of LED irradiation on delaying the senescence of pak-choi. LED irradiation represents a useful approach for extending the shelf life of pak-choi.

SRNAome and transcriptome analysis provide insight into strawberry fruit ripening

Strawberry fruit ripening is a complex process affected by multiple factors at different regulation levels. To elucidate the regulation mechanisms, the combined analysis of sRNAome and transcriptome were used. A total of 124 known and 190 novel miRNAs were found, 62 of them were significantly differentially expressed (DE). The targets of the DE miRNAs were parsed and several TFs, such as SPL, ARF, WRKY, and TCP, were found to be involved in ripening. Elevated CO₂ can significantly postpone ripening and miR156, miR166f, miR171a, and miR171d were the DE miRNAs. Transcriptome analysis found 313 DE genes related to fruit ripening, including cell wall metabolism-related genes, color-related genes, ethylene-related genes, and genes encoding TFs such as MYB, SPL, NAC, TCP, and ARF. Based on above, a combined regulatory model involved in fruit ripening was created. These results provide valuable information for understanding the complicated coordinated regulatory network of strawberry fruit ripening.

LncRNA PVT1 Enhances Proliferation and Cisplatin Resistance via Regulating miR-194-5p/HIF1a Axis in Oral Squamous Cell Carcinoma

Background

Oral squamous cell carcinoma (OSCC) is the most frequent oral malignancy. Recent studies have revealed that long non-coding RNA (lncRNA) PVT1 plays important roles in the pathogenesis of various cancers. However, the functional roles of PVT1 in OSCC progression and cisplatin resistance have not been elucidated.

Material and Methods

In this study, PVT1 expression level in cisplatin-sensitive and cisplatin-resistant OSCC tissues and cell lines was determined using qRT-PCR. Gain-of-function and loss-of-function assays were performed to explore the biological roles of PVT1 in OSCC cell proliferation and cisplatin resistance. Western blot, luciferase reporter assay and bioinformatics analysis were employed to investigate the underlying mechanism of PVT1 in OSCC progression.

Results

Here, we found that PVT1 was frequently up-regulated in cisplatin-resistant tissues and cell lines and strongly correlated with worse overall survival. Functional studies showed that PVT1 promoted OSCC cell proliferation and cisplatin resistance. Mechanistic investigation revealed that PVT1 could positively regulate HIF1a expression via its competing endogenous RNA (ceRNA) activity on miR-194-5p. In addition, miR-194-5p conversely correlated with PVT1 and HIF1a expression in OSCC samples. More importantly, HIF1a knock-down or miR-194-5p overexpression reversed PVT1-induced promotion of OSCC cell proliferation and cisplatin resistance.

Conclusion

Our results indicated that PVT1 functions as an oncogene involved in OSCC cell proliferation and cisplatin-resistance and may serve as a novel therapeutic target for OSCC treatment.

An untargeted metabolomic approach reveals significant postharvest alterations in vitamin metabolism in response to LED irradiation in pak-choi (Brassica campestris L. ssp. chinensis (L.) Makino var. communis Tsen et Lee)

The main objective of this study was to investigate the effect of low-level light emitting diode (LED) irradiation on the metabolite profile of pak-choi. A total of 633 different molecular features (MFs) were identified among sample groups (initial, dark-treated, light-treated) using an untargeted metabolomic approach. The identified metabolites were associated with 24 different metabolic pathways. Four of the pathways including carbon pool by folate, folate biosynthesis, thiamine metabolism, and glutathione metabolism, all of which are associated with vitamin biosynthesis, changed significantly. Metabolites in four of the pathways exhibited significant differences from the control in response to LED irradiation. Additionally, porphyrin and chlorophyll metabolism, as well as glucosinolate biosynthesis, riboflavin metabolism, and carotenoid biosynthesis were positively induced by LED irradiation. These results indicate that postharvest LED illumination represents a potential tool for modifying the metabolic profile of pak-choi to maintain quality and nutritional levels.

Network analysis of noncoding RNAs in pepper provides insights into fruit ripening control

Pepper is an important vegetable worldwide and is a model plant for nonclimacteric fleshy fruit ripening. Drastic visual changes and internal biochemical alterations are involved in fruit coloration, flavor, texture, aroma, and palatability to animals during the pepper fruit ripening process. To explore the regulation of bell pepper fruit ripening by noncoding RNAs (ncRNAs), we examined their expression profiles; 43 microRNAs (miRNAs), 125 circular RNAs (circRNAs), 366 long noncoding RNAs (lncRNAs), and 3266 messenger RNAs (mRNAs) were differentially expressed (DE) in mature green and red ripe fruit. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses revealed that the targets of the DE ncRNAs and DE mRNAs included several kinds of transcription factors (TFs) (ERF, bHLH, WRKY, MYB, NAC, bZIP, and ARF), enzymes involved in cell wall metabolism (beta-galactosidase, beta-glucosidase, beta-amylase, chitinase, pectate lyase (PL), pectinesterase (PE) and polygalacturonase (PG)), enzymes involved in fruit color accumulation (bifunctional 15-cis-phytoene synthase, 9-cis-epoxycarotenoid dioxygenase, beta-carotene hydroxylase and carotene epsilon-monooxygenase), enzymes associated with fruit flavor and aroma (glutamate-1-semialdehyde 2,1-aminomutase, anthocyanin 5-aromatic acyltransferase, and eugenol synthase 1) and enzymes involved in the production of ethylene (ET) (ACO1/ACO4) as well as other plant hormones such as abscisic acid (ABA), auxin (IAA), and gibberellic acid (GA). Based on accumulation profiles, a network of ncRNAs and mRNAs associated with bell pepper fruit ripening was developed that provides a foundation for further developing a more refined understanding of the molecular biology of fruit ripening.