Zinc-glutathione mitigates alcohol-induced intestinal and hepatic injury by modulating intestinal zinc-transporters in mice.

Long-term alcohol overconsumption impairs intestinal and hepatic structure and function, along with dysregulation of zinc homeostasis. We previously found that zinc-glutathione (Zn-GSH) complex effectively suppressed alcohol-induced liver injury in mice. This study was undertaken to test the hypothesis that Zn-GSH suppresses alcohol-induced liver injury by modulating intestinal zinc transporters. Mice were subjected to long-term ethanol feeding, as per the NIAAA model, with groups receiving either an ethanol diet alone or an ethanol diet supplemented with Zn-GSH. Treatment groups were carefully monitored for alcohol consumption and subjected to a final binge drinking exposure. The results showed that Zn-GSH increased the survival rate and decreased the recovery time from binge drinking-induced drunkenness. Histopathological analyses demonstrated a reduction in liver steatosis and the preservation of intestinal integrity by Zn-GSH. It was observed that Zn-GSH prevented the reduction of Zn and GSH levels while increasing alcohol dehydrogenase and aldehyde dehydrogenase in both liver and intestine. Importantly, the expression and protein abundance of zinc transporters ZnT-1, ZIP-1, ZIP-4, ZIP-6, and ZIP-14, all of which are critically involved in intestinal zinc transport and homeostasis, were significantly increased or preserved by Zn-GSH in response to alcohol exposure. This study thus highlights the critical role of Zn-GSH in maintaining intestinal zinc homeostasis by modulating zinc transporters, thereby preventing alcohol-induced intestinal and hepatic injury.

Preparation of white rot fungal inoculum and its application to bioremediation of chlorimuron-ethyl-contaminated soil.

Chlorimuron-ethyl is currently the primary herbicide used for chemical weed control in a soybean field. In this study, a solid microbial inoculum (corn stalk-white rot fungus (W-1)) was prepared for the remediation of farmland soil contaminated by chlorimuron-ethyl. Firstly, the preparation method of the microbial inoculum was studied. Secondly, the degradation rate of the chlorimuron-ethyl in the ground by the solid microbial inoculum is improved by optimizing the proportion of the protective agent. Then the effects of applying solid microbial inoculum, free bacteria and corn straw on the degradation rate of chlorimuron-ethyl in soil were weighed. Finally, Illumina MiSeq sequencing was used to measure the composition and diversity of bacterial and fungal communities in the ground before and after using microbial inoculum. The degradation rate of chlorimuron-ethyl in soil by solid microbial inoculum was 84.87% after 20 d using corn straw as the support, room temperature drying, 4% Ca3(PO4)2 as the protective drying agent, and 1%(w) dextrin as the ultraviolet protective agent. Inoculation of white rot fungi could significantly affect the community structure of bacteria and fungi in the soil, making the chlorimuron-ethyl degrading communities become the dominant communities and playing an essential role in the degradation of chlorimuron-ethyl. The results showed that using solid microbial inoculum was an effective way to repair farmland soil polluted by chlorimuron-ethyl.

Interface Passivation of a Pyridine-Based Bifunctional Molecule for Inverted Perovskite Solar Cells.

Organic-inorganic hybrid perovskite solar cells (PSCs) have recently been demonstrated to be promising renewable harvesters because of their prominent photovoltaic power conversion efficiency (PCE), although their stability and efficiency still have not reached commercial criteria. Trouble-oriented analyses showcase that defect reduction among the grain boundaries and interfaces in the prepared perovskite polycrystalline films is a practical strategy, which has prompted researchers to develop functional molecules for interface passivation. Herein, the pyridine-based bifunctional molecule dimethylpyridine-3,5-dicarboxylate (DPDC) was employed as the interface between the electron-transport layer and perovskite layer, which achieved a champion PCE of 21.37% for an inverted MAPbI3-based PSC, which was greater than 18.64% for the control device. The mechanistic studies indicated that the significantly improved performance was mainly attributed to the remarkably enhanced fill factor with a value greater than 83%, which was primarily due to the nonradiative recombination suppression offered by the passivation effect of DPDC. Moreover, the promoted carrier mobility together with the enlarged crystal size contributed to a higher short-circuit current density. In addition, an increase in the open-circuit voltage was also observed in the DPDC-treated PSC, which benefited from the improved work function for reducing the energy loss during carrier transport. Furthermore, the DPDC-treated PSC showed substantially enhanced stability, with an over 80% retention rate of its initial PCE value over 300 h even at a 60% relative humidity level, which was attributed to the hydrophobic nature of the DPDC molecule and effective defect passivation. This work is expected not only to serve as an effective strategy for using a pyridine-based bifunctional molecule to passivate perovskite interfaces to enhance photovoltaic performance but also to shed light on the interface passivation mechanism.

The Effects of a Nonpharmacological Intervention Practice for Older Adults with Mild Cognitive Impairment and Their Family Caregivers in China.

Mild cognitive impairment (MCI) marks a critical phase in the progression to dementia. In our study, social workers utilized the Multicomponent Nonpharmacological Intervention Approach (MCNIA) to aid MCI participants (N = 52) and their caregivers, dividing into intervention and control groups. The intervention group underwent an additional regimen of non-pharmacological therapies besides pharmacological treatment. Our findings highlighted that: 1) MCNIA significantly enhanced cognitive and daily living abilities in the intervention group; 2) Caregivers experienced reduced burdens and improved social support; 3) Correlation analyses involving biomarkers indicated that MCNIA was particularly effective in alleviating depression in those with slightly more severe cognitive impairment.

Hierarchical Hollow TiO2@Bi2WO6 with Light-Driven Excited Bi(3-x)+ Sites for Efficient Photothermal Catalytic CO2 Reduction.

Converting CO2 into valuable chemicals via sustainable energy sources is indispensable for human development. Photothermal catalysis combines the high selectivity of photocatalysis and the high yield of thermal catalysis, which is promising for CO2 reduction. However, the present photothermal catalysts suffer from low activity due to their poor light absorption ability and fast recombination of photogenerated electrons and holes. Here, a TiO2@Bi2WO6 heterojunction photocatalyst featuring a hierarchical hollow structure was prepared by an in situ growth method. The visible light absorption and photothermal effect of the TiO2@Bi2WO6 photocatalyst is promoted by a hierarchical hollow structure, while the recombination phenomenon is significantly mitigated due to the construction of the heterojunction interface and the existence of excited Bi(3-x)+ sites. Such a catalyst exhibits excellent photothermal performance with a CO yield of 43.7 µmol h-1 g-1, which is 15 and 4.7 times higher than that of pure Bi2WO6 and that of physically mixed TiO2/Bi2WO6, respectively. An in situ study shows that the pathway for the transformation of CO2 into CO over our TiO2@Bi2WO6 proceeds via two important intermediates, including COO- and COOH-. Our work provides a new idea of excited states for the design and synthesis of highly efficient photothermal catalysts for CO2 conversion.

A nonsynonymous mutation in BhLS, encoding an acyl-CoA N-acyltransferase leads to fruit and seed size variation in wax gourd (Benincasa hispida).

Wax gourd (Benincasa hispida (Thunb.) Cogn., 2n = 2x = 24) is an economically important vegetable crop cultivated widely in many tropical and subtropical regions, including China, India, and Japan. Both fruit and seeds are prized agronomic attributes in wax gourd breeding and production. However, the genetic mechanisms underlying these traits remain largely unexplored. In this study, we observed a strong correlation between fruit size and seed size variation in our mapping population, indicating genetic control by a single gene, BhLS, with large size being dominant over small. Through bulk segregant analysis sequencing and fine mapping with a large F2 population, we precisely located the BhLS gene within a 47.098-kb physical interval on Chromosome 10. Within this interval, only one gene, Bhi10M000649, was identified, showing homology to Arabidopsis HOOKLESS1. A nonsynonymous mutation (G to C) in the second exon of Bhi10M000649 was found to be significantly associated with both fruit and seed size variation in wax gourd. These findings collectively highlight the pleiotropic effect of the BhLS gene in regulating fruit and seed size in wax gourd. Our results offer molecular insights into the variation of fruit and seed size in wax gourd and establish a fundamental framework for breeding wax gourd cultivars with desired traits.

TRIM6 Promotes ROS-Mediated Inflammasome Activation and Pyroptosis in Renal Tubular Epithelial Cells via Ubiquitination and Degradation of GPX3 Protein.

BACKGROUND: Pyroptosis is a critical form of cell death during the development of chronic kidney disease (CKD). Tripartite motif 6 (TRIM6) is an E3-ubiquitin ligase that participates in the progression renal fibrosis (RF). The aim of this study was to investigate the roles of TRIM6 and Glutathione peroxidase 3 (GPX3) in oxidative stress-induced inflammasome activation and pyroptosis in Ang-II treated renal tubular epithelial cells. METHODS: To study its role in RF, TRIM6 expression was either reduced or increased in human kidney-2 (HK2) cells using lentivirus, and Ang-II, NAC and BMS-986299 were served as reactive oxygen species (ROS) inducer, ROS scavenger and NLRP3 agonist respectively. Pyroptosis and mitochondrial ROS were measured by flow cytometry. The levels of malondialdehyde (MDA), glutathione (GSH), and superoxide dismutase (SOD) were determined using commercial kits, while the levels of IL-1ß, IL-18, IL-6, and tumor necrosis factor-α (TNF-α) were determined by Enzyme-Linked Immunosorbent Assay (ELISA). Co-immunoprecipitation (Co-IP) assay was used to evaluate the interaction between TRIM6 and GPX3. Reverse transcription-polymerase chain reaction (RT-PCR) and western blot were used to measure mRNA and protein expression, respectively. RESULTS: Treatment with Angiotensin II (Ang II) increased the protein and mRNA levels of TRIM6 in HK2 cells. Ang II also increased mitochondrial ROS production and the malondialdehyde (MDA) level, but decreased the levels of GSH and SOD. In addition, Ang II enhanced HK2 cell pyroptosis, increased the levels of IL-1ß, IL-18, IL-6, and TNF-α, and promoted the expression of active IL-1ß, NLRP3, caspase-1, and GSDMD-N proteins. These effects were reversed by knockdown of TRIM6 and by treatment with N-acetyl-L-cysteine (NAC), a ROS scavenger. BMS-986299, an NLRP3 agonist treatment, did not affect ROS production in HK2 cells exposed to Ang II combined with NAC, but cell pyroptosis and inflammation were aggravated. Moreover, the overexpression of TRIM6 in HK2 cells resulted in similar effects to Ang II. NAC and GPX3 overexpression in HK2 cells could reverse ROS production, inflammation, and pyroptosis induced by TRIM6 overexpression. TRIM6 overexpression decreased the GPX3 protein level by promoting its ubiquitination, without affecting the GPX3 mRNA level. Thus, TRIM6 facilitates GPX3 ubiquitination, contributing to increased ROS levels and pyroptosis in HK2 cells. CONCLUSIONS: TRIM6 increases oxidative stress and promotes the pyroptosis of HK2 cells by regulating GPX3 ubiquitination. These findings could contribute to the development of novel drugs for the treatment of RF.

Study on Fu-Fang-Jin-Qian-Cao Inhibiting Autophagy in Calcium Oxalate-induced Renal Injury by UHPLC/Q-TOF-MS-based Metabonomics and Network Pharmacology Approaches.

INTRODUCTION: Fu-Fang-Jin-Qian-Cao is a Chinese herbal preparation used to treat urinary calculi. Fu-Fang-Jin-Qian-Cao can protect renal tubular epithelial cells from calcium oxalateinduced renal injury by inhibiting ROS-mediated autopathy. The mechanism still needs further exploration. Metabonomics is a new subject; the combination of metabolomics and network pharmacology can find pathways for drugs to act on targets more efficiently. METHODS: Comprehensive metabolomics and network pharmacology to study the mechanism of Fu-Fang-Jin-Qian-Cao inhibiting autophagy in calcium oxalate-induced renal injury. Based on UHPLC-Q-TOF-MS, combined with biochemical analysis, a mice model of Calcium oxalateinduced renal injury was established to study the therapeutic effect of Fu-Fang-Jin-Qian-Cao. Based on the network pharmacology, the target signaling pathway and the protective effect of Fu- Fang-Jin-Qian-Cao on Calcium oxalate-induced renal injury by inhibiting autophagy were explored. Autophagy-related proteins LC3-II, BECN1, ATG5, and ATG7 were studied by immunohistochemistry. RESULTS: Combining network pharmacology and metabolomics, 50 differential metabolites and 2482 targets related to these metabolites were found. Subsequently, the targets enriched in PI3KAkt, MAPK and Ras signaling pathways. LC3-II, BECN1, ATG5 and ATG7 were up-regulated in Calcium oxalate-induced renal injury. All of them could be reversed after the Fu-Fang-Jin-Qian- Cao treatment. CONCLUSIONS: Fu-Fang-Jin-Qian-Cao can reverse ROS-induced activation of the MAPK signaling pathway and inhibition of the PI3K-Akt signaling pathway, thereby reducing autophagy damage of renal tubular epithelial cells in Calcium oxalate-induced renal injury.

The Antiobesity Effects and Potential Mechanisms of Theaflavins.

Theaflavins are the characteristic polyphenols in black tea which can be enzymatically synthesized. In this review, the effects and molecular mechanisms of theaflavins on obesity and its comorbidities, including dyslipidemia, insulin resistance, hepatic steatosis, and atherosclerosis, were summarized. Theaflavins ameliorate obesity potentially via reducing food intake, inhibiting pancreatic lipase to reduce lipid absorption, activating the adenosine monophosphate-activated protein kinase (AMPK), and regulating the gut microbiota. As to the comorbidities, theaflavins ameliorate hypercholesterolemia by inhibiting micelle formation to reduce cholesterol absorption. Theaflavins improve insulin sensitivity by increasing the signaling of protein kinase B, eliminating glucose toxicity, and inhibiting inflammation. Theaflavins ameliorate hepatic steatosis via activating AMPK. Theaflavins reduce atherosclerosis by upregulating nuclear factor erythropoietin-2-related factor 2 signaling and inhibiting plasminogen activator inhibitor 1. In randomized controlled trails, black tea extracts containing theaflavins reduced body weight in overweight people and improved glucose tolerance in healthy adults. The amelioration on the hyperlipidemia and the prevention of coronary artery disease by black tea extracts were supported by meta-analysis.

The role of pulmonary rehabilitation in idiopathic pulmonary fibrosis: An overview of systematic reviews.

BACKGROUND: The role of pulmonary rehabilitation (PR) in idiopathic pulmonary fibrosis (IPF) has been studied in several systematic reviews (SRs), but no definitive conclusions have been drawn due to the wide variation in the quality and outcomes of the studies. And there are no studies to assess the quality of relevant published SRs. This overview aims to determine the effectiveness of PR in patients with IPF and to summarize and critically evaluate the risk of bias, methodological, and evidence quality of SRs on this related topic. METHODS: With no language restrictions, eight databases were searched from inception to March 10, 2023. The literature search, screening, and data extraction were carried out separately by two reviewers. We assessed the risk of bias using the ROBIS tool, the reporting quality using PRISMA statements, the methodological quality using AMSTAR-2, and the evidence quality using Grades of Recommendations, Assessment, Development, and Evaluation (GRADE). RESULTS: Seven SRs from 2018-2023 (including 1836 participants) on PR for the treatment of IPF were selected, all of which included patients with a definitive diagnosis of IPF. After strict evaluation by the ROBIS tool and AMSTAR-2 tool, 42.86% of the SRs had a high risk of bias and 85.71% of the SRs had critically low methodological quality in this overview. PR might be effective for patients with IPF on exercise capacity, quality of life, and pulmonary function-related outcomes, but we did not find high quality evidence to confirm the effectiveness. CONCLUSION: PR may appear to be an effective and safe treatment for patients with IPF, but the results of this overview should be interpreted dialectically and with caution. Further high-quality, rigorous studies are urgently needed to draw definitive conclusions and provide scientific evidence.

Detecting the Unseen: Understanding the Mechanisms and Working Principles of Earthquake Sensors.

The application of movement-detection sensors is crucial for understanding surface movement and tectonic activities. The development of modern sensors has been instrumental in earthquake monitoring, prediction, early warning, emergency commanding and communication, search and rescue, and life detection. There are numerous sensors currently being utilized in earthquake engineering and science. It is essential to review their mechanisms and working principles thoroughly. Hence, we have attempted to review the development and application of these sensors by classifying them based on the timeline of earthquakes, the physical or chemical mechanisms of sensors, and the location of sensor platforms. In this study, we analyzed available sensor platforms that have been widely used in recent years, with satellites and UAVs being among the most used. The findings of our study will be useful for future earthquake response and relief efforts, as well as research aimed at reducing earthquake disaster risks.

Responses of differential metabolites and pathways to high temperature in cucumber anther.

Cucumber is one of the most important vegetable crops, which is widely planted all over the world. Cucumber always suffers from high-temperature stress in South China in summer. In this study, liquid chromatography-mass spectrometry (LC-MS) analysis was used to study the differential metabolites of cucumber anther between high-temperature (HT) stress and normal condition (CK). After HT, the pollen fertility was significantly reduced, and abnormal anther structures were observed by the paraffin section. In addition, the metabolomics analysis results showed that a total of 125 differential metabolites were identified after HT, consisting of 99 significantly upregulated and 26 significantly downregulated metabolites. Among these differential metabolites, a total of 26 related metabolic pathways were found, and four pathways showed significant differences, namely, porphyrin and chlorophyll metabolism; plant hormone signal transduction; amino sugar and nucleotide sugar metabolism; and glycine, serine, and threonine metabolism. In addition, pollen fertility was decreased by altering the metabolites of plant hormone signal transduction and amino acid and sugar metabolism pathway under HT. These results provide a comprehensive understanding of the metabolic changes in cucumber anther under HT.

Fine mapping and candidate gene analysis of gynoecy trait in chieh-qua (Benincasa hispida Cogn. var. chieh-qua How).

Gynoecy demonstrates an earlier production of hybrids and a higher yield and improves the efficiency of hybrid seed production. Therefore, the utilization of gynoecy is beneficial for the genetic breeding of chieh-qua. However, little knowledge of gynoecious-related genes in chieh-qua has been reported until now. Here, we used an F2 population from the cross between the gynoecious line 'A36' and the monoecious line 'SX' for genetic mapping and revealed that chieh-qua gynoecy was regulated by a single recessive gene. We fine-mapped it into a 530-kb region flanked by the markers Indel-3 and KASP145 on Chr.8, which harbors eight candidate genes. One of the candidate genes, Bhi08G000345, encoding networked protein 4 (CqNET4), contained a non-synonymous SNP resulting in the amino acid substitution of isoleucine (ATA; I) to methionine (ATG; M). CqNET4 was prominently expressed in the female flower, and only three genes related to ethylene synthesis were significantly expressed between 'A36' and 'SX.' The results presented here provide support for the CqNET4 as the most likely candidate gene for chieh-qua gynoecy, which differed from the reported gynoecious genes.

Simultaneous Ring Contraction and Expansion Reaction: Electrosynthesis of Heterocycle-Fused Fulleroids and Photovoltaic Application.

Simultaneous electrochemical ring contraction and expansion reactions remain unexplored to date. Herein, the reductive electrosynthesis of heterocycle-fused fulleroids from fullerotetrahydropyridazines and electrophiles in the presence of a trace amount of oxygen has been achieved with concurrent ring contraction and ring expansion. When trifluoroacetic acid and alkyl bromides are employed as electrophiles, heterocycle-fused fulleroids with a 1,1,2,6-configuration are regioselectively formed. In contrast, heterocycle-fused fulleroids with a 1,1,4,6-configuration are regioselectively produced as two separable stereoisomers if phthaloyl chloride is used as the electrophile. The reaction proceeds through multiple steps of electroreduction, heterocycle ring-opening, oxygen oxidation, heterocycle contraction, fullerene cage expansion, and nucleophilic addition. The structures of these fulleroids have been determined by spectroscopic data and single-crystal X-ray diffraction analyses. The observed high regioselectivities have been rationalized by theoretical calculations. Representative fulleroids have been applied in organic solar cells as the third component and exhibit good performance.

Zinc-glutathione in Chinese Baijiu prevents alcohol-associated liver injury.

Zinc depletion is associated with alcohol-associated liver injury. We tested the hypothesis that increasing zinc availability along with alcohol consumption prevents alcohol-associated liver injury. Zinc-glutathione (ZnGSH) was synthesized and directly added to Chinese Baijiu. Mice were administered a single gastric dose of 6 g/kg ethanol in Chinese Baijiu with or without ZnGSH. ZnGSH in Chinese Baijiu did not change the likeness of the drinkers but significantly reduced the recovery time from drunkenness along with elimination of high-dose mortality. ZnGSH in Chinese Baijiu decreased serum AST and ALT, suppressed steatosis and necrosis, and increased zinc and GSH concentrations in the liver. It also increased alcohol dehydrogenase and aldehyde dehydrogenase in the liver, stomach, and intestine and reduced acetaldehyde in the liver. Thus, ZnGSH in Chinese Baijiu prevents alcohol-associated liver injury by increasing alcohol metabolism timely with alcohol consumption, providing an alternative approach to the management of alcohol-associated drinking.

A chromosome-level reference genome of the wax gourd (Benincasa hispida).

The wax gourd (Benincasa hispida), the only species in the genus Benincasa, is an important crop native to Asia that has been widely planted for multi-purpose uses. The first wax gourd draft genome was published three years ago, but it was incomplete and highly-fragmented due to data and technical limitations. Herein, we report a new chromosome-level genome assembly and annotation of B. hispida. We generated 974.87 Mb of unitigs with N50 size of 2.43 Mb via a hybrid assembly strategy by using PacBio long reads and Illumina short reads. We then joined them into scaffolds with Hi-C data, resulting 1862 scaffolds with a total length of 975.62 Mb, and 94.92% of the length (926.05 Mb) is contained in the 12 largest scaffolds corresponding to the 12 chromosomes of B. hispida. We predicted 37,092 protein-coding genes, and 85.05% of them were functionally annotated. This chromosome-level reference genome provides significant improvement to the earlier version of draft genome and would be valuable resource for research and molecular breeding of the wax gourd.

Design and kinematics of a tube-shaped multidirectional bending robotic device using slackened SMA wires for transurethral ureterolithotripsy.

PURPOSE: The complex and elaborate structure of the urinary system presents surgeons with difficulty in using a ureteroscope with a fixed optical fiber to reach the targeted calculus. To address this challenge, a robotic device is required to control the direction of laser irradiation position independently in ureteroscopes. METHOD: A continuum robotic device was designed and fabricated. The device is constructed with three slackened shape memory alloy (SMA) wires to control the laser irradiation position of the optical fiber combined with the view of the camera on the tip of the ureteroscope. Kinematics analysis and experimental evaluation reveal the capability of the device. RESULTS: The structure of the device is the same as a single-joint continuum robot. This device is unique because of the tiny diameter of 1.1 mm which can be used inside the ureteroscope through a Ø1.2 mm inner channel into the kidney for transurethral ureterolithotripsy. Kinematic analysis revealed the relationship among space coordinates, angles of bending, and direction and SMA wires length. The maximum bending angle was around 25° when the current value was 350 mA on a single SMA wire. The device could achieve multi-directional bending by allocating the values of current on SMA wires, separately. CONCLUSION: This device offers a major advancement in small size and dexterity in medical robotics. Combined with a proper control system, this device could simplify the operation and improve the efficiency of the transurethral ureterolithotripsy.

Genome-Wide Identification of the SAUR Gene Family in Wax Gourd (Benincasa hispida) and Functional Characterization of BhSAUR60 during Fruit Development.

The wax gourd (Benincasa hispida) is an important vegetable crop whose fruits contain nutrients and metabolites. Small auxin upregulated RNA (SAUR) genes constitute the largest early auxin-responsive gene family and regulate various biological processes in plants, although this gene family has not been studied in the wax gourd. Here, we performed genome-wide identification of the SAUR gene family in wax gourds and analyzed their syntenic and phylogenetic relationships, gene structures, conserved motifs, cis-acting elements, and expression patterns. A total of 68 SAUR (BhSAUR) genes were identified, which were distributed on nine chromosomes with 41 genes in two clusters. More than half of the BhSAUR genes were derived from tandem duplication events. The BhSAUR proteins were classified into seven subfamilies. BhSAUR gene promoters contained cis-acting elements involved in plant hormone and environmental signal responses. Further expression profiles showed that BhSAUR genes displayed different expression patterns. BhSAUR60 was highly expressed in fruits, and overexpression led to longer fruits in Arabidopsis. In addition, the plants with overexpression displayed longer floral organs and wavy stems. In conclusion, our results provide a systematic analysis of the wax gourd SAUR gene family and facilitate the functional study of BhSAUR60 during wax gourd fruit development.

Genome-wide association study and genetic mapping of BhWAX conferring mature fruit cuticular wax in wax gourd.

BACKGROUND: Wax gourd [Benincasa hispida (Thunb) Cogn. (2n = 2x = 24)] is an economically important vegetable crop of genus Benincasa in the Cucurbitaceae family. Fruit is the main consumption organ of wax gourd. The mature fruit cuticular wax (MFCW) is an important trait in breeding programs, which is also of evolutionary significance in wax gourd. However, the genetic architecture of this valuable trait remains unrevealed. RESULTS: In this study, genetic analysis revealed that the inheritance of MFCW was controlled by a single gene, with MFCW dominant over non-MFCW, and the gene was primarily named as BhWAX. Genome-wide association study (GWAS) highlighted a 1.1 Mb interval on chromosome 9 associated with MFCW in wax gourd germplasm resources. Traditional fine genetic mapping delimited BhWAX to a 0.5 Mb region containing 12 genes. Based on the gene annotation, expression analysis and co-segregation analysis, Bhi09G001428 that encodes a membrane bound O-acyltransferase (MBOAT) was proposed as the candidate gene for BhWAX. Moreover, it was demonstrated that the efficiency of a cleaved amplified polymorphic sequences (CAPS) marker in the determination of MFCW in wax gourd reached 80%. CONCLUSIONS: In closing, the study identified the candidate gene controlling MFCW and provided an efficient molecular marker for the trait in wax gourd for the first time, which will not only be beneficial for functional validation of the gene and marker-assisted breeding of wax gourd, but also lay a foundation for analysis of its evolutionary meaning among cucurbits.

Cytological, genetic and transcriptomic characterization of a cucumber albino mutant.

Photosynthesis, a fundamental process for plant growth and development, is dependent on chloroplast formation and chlorophyll synthesis. Severe disruption of chloroplast structure results in albinism of higher plants. In the present study, we report a cucumber albino alc mutant that presented white cotyledons under normal light conditions and was unable to produce first true leaf. Meanwhile, alc mutant could grow creamy green cotyledons under dim light conditions but died after exposure to normal light irradiation. No chlorophyll and carotenoid were detected in the alc mutant grown under normal light conditions. Using transmission electron microscopy, impaired chloroplasts were observed in this mutant. The genetic analysis indicated that the albino phenotype was recessively controlled by a single locus. Comparative transcriptomic analysis between the alc mutant and wild type revealed that genes involved in chlorophyll metabolism and the methylerythritol 4-phosphate pathway were affected in the alc mutant. In addition, three genes involved in chloroplast development, including two FtsH genes and one PPR gene, were found to have negligible expression in this mutant. The quality of RNA sequencing results was further confirmed by real-time quantitative PCR analysis. We also examined 12 homologous genes from alc mutant in other plant species, but no genetic variation in the coding sequences of these genes was found between alc mutant and wild type. Taken together, we characterized a cucumber albino mutant with albinism phenotype caused by chloroplast development deficiency and this mutant can pave way for future studies on plastid development.