Conditioned medium from human dental pulp stem cells treats spinal cord injury by inhibiting microglial pyroptosis

Human dental pulp stem cell transplantation has been shown to be an effective therapeutic strategy for spinal cord injury.However,whether the human dental pulp stem cell secretome can contribute to functional recovery after spinal cord injury remains unclear.In the present study,we established a rat model of spinal cord injury based on impact injury from a dropped weight and then intraperitoneally injected the rats with conditioned medium from human dental pulp stem cells.We found that the conditioned medium effectively promoted the recovery of sensory and motor functions in rats with spinal cord injury,decreased expression of the microglial pyroptosis markers NLRP3,GSDMD,caspase-1,and interleukin-1β,promoted axonal and myelin regeneration,and inhibited the formation of glial scars.In addition,in a lipopolysaccharide-induced BV2 microglia model,conditioned medium from human dental pulp stem cells protected cells from pyroptosis by inhibiting the NLRP3/caspase-1/interleukin-1βpathway.These results indicate that conditioned medium from human dental pulp stem cells can reduce microglial pyroptosis by inhibiting the NLRP3/caspase-1/interleukin-1βpathway,thereby promoting the recovery of neurological function after spinal cord injury.Therefore,conditioned medium from human dental pulp stem cells may become an alternative therapy for spinal cord injury.

RPLP0/TBP are the most stable reference genes for human dental pulp stem cells under osteogenic differentiation

BACKGROUND Validation of the reference gene(RG)stability during experimental analyses is essential for correct quantitative real-time polymerase chain reaction(RT-qPCR)data normalisation.Commonly,in an unreliable way,several studies use genes involved in essential cellular functions[glyceraldehyde-3-phosphate dehydro-genase(GAPDH),18S rRNA,andβ-actin]without paying attention to whether they are suitable for such experimental conditions or the reason for choosing such genes.Furthermore,such studies use only one gene when Minimum Information for Publication of Quantitative Real-Time PCR Experiments guidelines recom-mend two or more genes.It impacts the credibility of these studies and causes dis-tortions in the gene expression findings.For tissue engineering,the accuracy of gene expression drives the best experimental or therapeutical approaches.We cultivated DPSCs under two conditions:Undifferentiated and osteogenic dif-ferentiation,both for 35 d.We evaluated the gene expression of 10 candidates for RGs[ribosomal protein,large,P0(RPLP0),TATA-binding protein(TBP),GAPDH,actin beta(ACTB),tubulin(TUB),aminolevulinic acid synthase 1(ALAS1),tyro-sine 3-monooxygenase/tryptophan 5-monooxygenase activation protein,zeta(YWHAZ),eukaryotic translational elongation factor 1 alpha(EF1a),succinate dehydrogenase complex,subunit A,flavoprotein(SDHA),and beta-2-micro-globulin(B2M)]every 7 d(1,7,14,21,28,and 35 d)by RT-qPCR.The data were analysed by the four main algorithms,ΔCt method,geNorm,NormFinder,and BestKeeper and ranked by the RefFinder method.We subdivided the samples into eight subgroups.RESULTS All of the data sets from clonogenic and osteogenic samples were analysed using the RefFinder algorithm.The final ranking showed RPLP0/TBP as the two most stable RGs and TUB/B2M as the two least stable RGs.Either theΔCt method or NormFinder analysis showed TBP/RPLP0 as the two most stable genes.However,geNorm analysis showed RPLP0/EF1αin the first place.These algorithms’two least stable RGs were B2M/GAPDH.For BestKeeper,ALAS1 was ranked as the most stable RG,and SDHA as the least stable RG.The pair RPLP0/TBP was detected in most subgroups as the most stable RGs,following the RefFinfer ranking.CONCLUSION For the first time,we show that RPLP0/TBP are the most stable RGs,whereas TUB/B2M are unstable RGs for long-term osteogenic differentiation of human DPSCs in traditional monolayers.

Multiple pulp stones emerge across all teeth during mixed dentition:A case report

BACKGROUND This paper reports a rare presentation of multiple pulp stones(PSs)emerging in all teeth during mixed dentition.It offers valuable insights into the clinical diagnosis,treatment,and prognosis of multiple PSs,shedding light on their occurrence during the mixed dentition period.CASE SUMMARY A 10-year-old girl presented with repeated pain in the mandibular right posterior teeth.Intraoral examination revealed carious lesions,abnormal tooth shapes,and anomalies in tooth number.Radiographic examinations showed multiple PSs with diverse shapes,sizes,and quantities in all teeth,alongside anomalies in tooth shape and number.Root canal therapy was initiated,but the patient initially lacked timely follow-up.Upon return for treatment completion,an extracted tooth revealed irregular calculus within the pulp cavity.CONCLUSION This case underscores the importance of considering multiple PSs in mixed dentition,necessitating comprehensive evaluation and management strategies.

γ-Aminobutyric acid alleviates litchi thaumatin-like protein-induced inflammation and reduces gut microbial translocation

Previous research reported litchi thaumatin-like protein(LcTLP)could lead to inflammation,which is a factor causing the adverse reactions after excessive intake of litchi.As a main amino acid in litchi pulp,γ-aminobutyric acid(GABA)was found with anti-inflammatory effect.Therefore,this study aimed to investigate the effects of GABA on LcTLP-induced inflammation through RAW264.7 macrophages and C57BL mice models.In vitro study showed GABA could effectively regulate the level of inflammatory cytokines(interleukin(IL)-1β,IL-6,IL-10,and prostaglandin E2)and Ca2+in cells,and inhibit the phosphorylation of p65,IκB,p38,c-Jun N-terminal kinase(JNK)and extracellular signal-regulated kinase(ERK).These results indicate GABA alleviated inflammation through nuclear factor-κB and mitogen-activated protein kinase pathway signaling pathways.In vivo experiment was performed to verify the anti-inflammatory effect of GABA,and the results demonstrated that GABA reduced the inflammation and oxidative stress in the liver of LcTLP-treated mice,as it down-regulated the pro-inflammatory cytokines,malondialdehyde,aspartate transferase,and alanine transaminase.The relative expression of phosphorylated p38,JNK and ERK in mice liver with GABA treatment were reduced to 65%,39%and 80%of the control group,respectively.Furthermore,GABA treatment enriched probiotic bacteria and decreased pathogenic bacteria in mice gut,which reveals GABA could effectively reduce the translocation of gut microbiota.

Optimizing hemicelluloses pre-extraction in eucalyptus kraft pulping:A pathway towards enhancing pulp mill biorefineries

A critical pathway towards enhancing pulp mill biorefineries is to integrate the extraction and utilization of hemicelluloses into the pulping processes.Hence,an industrial pre-extraction strategy for hemicelluloses targeting eucalyptus kraft pulping process was developed.Alkaline solution or pulping white liquor was used to pre-extract hemicelluloses before the actual pulping process.The response surface methodology(RSM)technique was applied to investigate the most suitable conditions to maximize the yield of these hemicelluloses while simultaneously minimizing the damage to pulp yields and properties.Temperature(105 to 155℃),alkali concentration(3%to 8%),sulfidity(20%to 30%)and retention time(19 to 221 min)were combined to evaluate their effects on hemicellulose yields and chemical structures.The optimal pre-extraction conditions identified in this work(5.75%NaOH concentration,25%sulfidity at 135℃for 60 min)successfully allowed recovering 4.8%of hemicelluloses(based on the wood dry mass)and limited damages to pulp yields and properties.The cellulose content in pulp can even be increased by about 10%.Hemicellulose emulsification properties were also evaluated,which were comparable to synthetic emulsifiers.This study provides an industrial pathway to effectively separate and utilize wood hemicelluloses from the pulping process,which has the potential to improve the economy and material utilization of pulp and paper mills.

Adrenaline in pulp capping treatment of reversible pulpitis

BACKGROUND The role of epinephrine in the treatment of pulp capping in patients with reversible pulpitis is not clear.AIM To explore the role of epinephrine in the treatment of pulp capping in patients with reversible pulpitis.METHODS A total of 100 patients with reversible pulpitis who were treated in Anhui Jieshou People's Hospital from January 2020 to December 2021 were included in the study.They were categorized into an observation group(n=50;treatment with adrenaline)and a control group(n=50;treatment with zinc oxide eugenol paste).The 24-h postoperative pain,regression time of gingival congestion and redness,clinical efficacy,and incidence of adverse reactions were compared between the groups.Patients were further categorized into the ineffective and effective treatment groups based on clinical efficacy.Logistic multiple regression analysis explored factors affecting the efficacy of pulp capping treatment.RESULTS A significant difference in 24-h postoperative pain was observed between the groups(P<0.05),with a higher proportion of grade I pain noted in the observation group than in the control group(P<0.01).The regression time of gingival congestion and swelling was lower in the observation group(2.61±1.44 d and 2.73±1.36 d,respectively)than in the control group(3.85±1.47 d and 4.28±1.61 d,respectively)(P<0.05).The 2-wk postoperative total effective rate was lower in the control group(80.00%)than in the observation group(94.00%)(P<0.05).The incidence of adverse reactions was not significantly different between the control(14.00%)and observation(12.00%)groups(P>0.05).The proportion of adrenaline usage was lower(P<0.05)and that of anaerobic digestion by Streptococcus and Fusobacterium nucleatum was higher in the ineffective treatment group than in the effective treatment group(P<0.05).Logistic multiple regression analysis revealed adrenaline as a protective factor(P<0.05)and anaerobic digestion by Streptococcus and F.nucleatum as risk factors for pulp capping in reversible pulpitis(P<0.05).CONCLUSION Adrenaline demonstrated therapeutic efficacy in pulp capping treatment for reversible pulpitis,reducing pain and improving clinical symptoms safely.It is a protective factor for pulp capping,whereas Streptococcus and F.nucleatum are risk factors.Targeted measures can be implemented to improve clinical efficacy.

Formulation of Infant Flours Based on Fonio Enriched with Bambara Groundnut Anacardium (Cashew) and African Locust Bean Fruit Pulp

Infant malnutrition is a significant issue in Côte d’Ivoire, and this study aims to address it by formulating infant flours using local ingredients. Fermentation, germination, and malting methods were used to enhance the quality of six formulated flours, all based on Fonio and supplemented with Bambara groundnut, African locust bean fruit pulp, and cashew kernels. Results showed that Fonio had the highest carbohydrate content, while Bambara groundnut and Cashew kernels were rich in protein and lipid content. African locust bean fruit pulp was rich in fiber and Vitamin C, with a high β-carotene value. The cashew kernel had the highest energy value. Regarding mineral composition, African locust bean fruit pulp had the highest potassium content, while Bambara groundnut and African locust bean fruit pulp were rich in sodium. Cashew kernel and Fonio had higher iron and calcium content. Bambara groundnut had a higher zinc content, while cashew kernel had a higher magnesium content. The formulated flours made from fermented Fonio grains and enriched with Bambara groundnut, African locust bean fruit pulp, and cashew kernel had varying protein, fiber, carbohydrate, ash, and fat contents. The flour formulated with sprouted Fonio and enriched with the same ingredients had higher protein content and energy value than the other fermented seed-based flours. The mixed flours produced with fermented seeds and the flour produced from sprouted seeds met international standards. Overall, these findings offer valuable insights into the nutritional composition of the formulated flours and their potential to combat infant malnutrition in Côte d’Ivoire.

Reducing Effect of Parkia biglobosa (Jacq.) R. Br. ex G. Don Fruit Pulp on Food Intake in Healthy NMRI Mice

Obesity is a chronic condition characterised by excess body fat that leads to increased body weight. One of the most effective ways to treat obesity is to use appetite suppressants to reduce food intake. This study aimed to evaluate in vivo reduction of food intake and weight gain caused by Parkia biglobosa (Pb) fruit pulp. Twenty-four healthy NMRI mice divided into four groups were used for the experiment. Group 1, considered the negative control, received distilled water. Groups 2, 3, and 4 were administered daily with 100, 250 and 500 mg/kg body weight of Pb fruit pulp powder suspension, respectively. The reduction in food intake was assessed in two phases: acute food intake for one day (24 h) and long-term food intake for seven weeks. Nutrient parameters and phenolic compounds in Pb fruit pulp were quantified. The results showed that Pb fruit pulp had a significant effect on reducing acute food intake. At a dose of 250 mg/kg, Pb had the best activity in reducing acute food intake, with an overall reduction rate of approximately 47.98% ± 1.17% compared to the control. Repeated daily administration inhibited food intake with all three doses for 13 days compared to control. Food intake was significantly decreased for up to 31 days by taking a 100 mg/kg dose of Pb (p = 0.0174). Weight gain was significantly lower (p = 0.0003) in mice treated with 100 mg/kg Pb than in controls at the end of 7 weeks. According to the nutritional composition study, Pb fruit pulp contains an abundance of total carbohydrates (68.81% ± 0.32%) and crude fiber (14.35% ± 0.21%). This study demonstrated that Pb fruit pulp effectively reduces food intake in healthy mice. Pb pulp’s richness in crude fiber and phenolic compounds makes it a potential aid in managing obesity.

Hepatocyte growth factor enhances the ability of dental pulp stem cells to ameliorate atherosclerosis in apolipoprotein E-knockout mice

BACKGROUND Atherosclerosis(AS),a chronic inflammatory disease of blood vessels,is a major contributor to cardiovascular disease.Dental pulp stem cells(DPSCs)are capable of exerting immunomodulatory and anti-inflammatory effects by secreting cytokines and exosomes and are widely used to treat autoimmune and inflam-mation-related diseases.Hepatocyte growth factor(HGF)is a pleiotropic cytokine that plays a key role in many inflammatory and autoimmune diseases.AIM To modify DPSCs with HGF(DPSC-HGF)and evaluate the therapeutic effect of DPSC-HGF on AS using an apolipoprotein E-knockout(ApoE-/-)mouse model and an in vitro cellular model.METHODS ApoE-/-mice were fed with a high-fat diet(HFD)for 12 wk and injected with DPSC-HGF or Ad-Null modified DPSCs(DPSC-Null)through tail vein at weeks 4,7,and 11,respectively,and the therapeutic efficacy and mechanisms were analyzed by histopathology,flow cytometry,lipid and glucose measurements,real-time reverse transcription polymerase chain reaction(RT-PCR),and enzyme-linked immunosorbent assay at the different time points of the experiment.An in vitro inflammatory cell model was established by using RAW264.7 cells and human aortic endothelial cells(HAOECs),and indirect co-cultured with supernatant of DPSC-Null(DPSC-Null-CM)or DPSC-HGF-CM,and the effect and mechanisms were analyzed by flow cytometry,RT-PCR and western blot.Nuclear factor-κB(NF-κB)activators and inhibitors were also used to validate the related signaling pathways.RESULTS DPSC-Null and DPSC-HGF treatments decreased the area of atherosclerotic plaques and reduced the expression of inflammatory factors,and the percentage of macrophages in the aorta,and DPSC-HGF treatment had more pronounced effects.DPSCs treatment had no effect on serum lipoprotein levels.The FACS results showed that DPSCs treatment reduced the percentages of monocytes,neutrophils,and M1 macrophages in the peripheral blood and spleen.DPSC-Null-CM and DPSC-HGF-CM reduced adhesion molecule expression in tumor necrosis factor-αstimulated HAOECs and regulated M1 polarization and inflammatory factor expression in lipopolysaccharide-induced RAW264.7 cells by inhibiting the NF-κB signaling pathway.CONCLUSION This study suggested that DPSC-HGF could more effectively ameliorate AS in ApoE-/-mice on a HFD,and could be of greater value in stem cell-based treatments for AS.

Human dental pulp stem/stromal cells in clinical practice

Dental pulp stem/stromal cells(DPSCs)are fibroblast-like,neural crest-derived,and multipotent cells that can differentiate into several lineages.They are relatively easy to isolate from healthy and inflamed pulps,with little ethical concerns and can be successfully cryopreserved and thawed.The therapeutic effects of DPSCs derived from animal or human sources have been extensively studied through in-vitro and in-vivo animal experiments and the findings indicated that DPSCs are effective not only for dental diseases but also for systemic diseases.Understanding that translational research is a critical step through which the fundamental scientific discoveries could be translated into applicable diagnostics and therapeutics that directly benefit humans,several clinical studies were carried out to generate evidence for the efficacy and safety of autogenous or allogeneic human DPSCs(hDPSCs)as a treatment modality for use in cell-based therapy,regenerative medicine/dentistry and tissue engineering.In clinical medicine,hDPSCs were effective for treating acute ischemic stroke and human exfoliated deciduous teeth-conditioned medium(SHED-CM)repaired vascular damage of the corpus cavernous,which is the main cause of erectile dysfunction.Whereas in clinical dentistry,autologous SHED was able to rege-nerate necrotic dental pulp after implantation into injured teeth,and micrografts enriched with autologous hDPSCs and collagen sponge were considered a treatment option for human intrabony defects.In contrast,hDPSCs did not add a significant regenerative effect when they were used for the treatment of post-extraction sockets.Large-scale clinical studies across diverse populations are still lacking to provide robust evidence on the safety and efficacy of hDPSCs as a new treatment option for various human diseases including dental-related problems.

Self-assembly of differentiated dental pulp stem cells facilitates spheroid human dental organoid formation and prevascularization

BACKGROUND The self-assembly of solid organs from stem cells has the potential to greatly expand the applicability of regenerative medicine.Stem cells can self-organise into microsized organ units,partially modelling tissue function and regeneration.Dental pulp organoids have been used to recapitulate the processes of tooth development and related diseases.However,the lack of vasculature limits the utility of dental pulp organoids.AIM To improve survival and aid in recovery after stem cell transplantation,we demonstrated the three-dimensional(3D)self-assembly of adult stem cell-human dental pulp stem cells(hDPSCs)and endothelial cells(ECs)into a novel type of spheroid-shaped dental pulp organoid in vitro under hypoxia and conditioned medium(CM).METHODS During culture,primary hDPSCs were induced to differentiate into ECs by exposing them to a hypoxic environment and CM.The hypoxic pretreated hDPSCs were then mixed with ECs at specific ratios and conditioned in a 3D environment to produce prevascularized dental pulp organoids.The biological characteristics of the organoids were analysed,and the regulatory pathways associated with angiogenesis were studied.RESULTS The combination of these two agents resulted in prevascularized human dental pulp organoids(Vorganoids)that more closely resembled dental pulp tissue in terms of morphology and function.Single-cell RNA sequencing of dental pulp tissue and RNA sequencing of Vorganoids were integrated to analyse key regulatory pathways associated with angiogenesis.The biomarkers forkhead box protein O1 and fibroblast growth factor 2 were identified to be involved in the regulation of Vorganoids.CONCLUSION In this innovative study,we effectively established an in vitro model of Vorganoids and used it to elucidate new mechanisms of angiogenesis during regeneration,facilitating the development of clinical treatment strategies.

Effects of Chitosan and Salicylic Acid on Cold Resistance of Litchi under Low Temperature

This paper focused on the effect of spraying chitosan and salicylic acid to Litchi under low temperature stress conditions.The physiology and biochemistry of litchi were studied as well.Results showed that the appropriate concentration of chitosan and salicylic acid treatment could effectively reduce injury caused by low temperature to litchi,compared with water control,chlorophyll,proline,soluble protein content of litchi after treatment and the activity of protective enzyme increasing significantly.However,the accumulation of resistance could significantly be improved.Furthermore,when 1 000 mg/L chitosan combined with 50 mg/L salicylic acid,the litchi acquired the best cold resistance capability.

An Effective Method for Extracting Total RNA from Young Embryo of Seedless Litchi

A total RNA extraction method for young embryo of seedless litchi was introduced. CTAB, Phenol （saturated with water）, chloroform, Guanidine isothioeyanate were used as main extraction reagents. Polyphenolie compounds were removed effectively by added PVP into the extraction buffer solution. RNA was purified intensively by phenol, chloroform extraction, and ethanol deposition after deposited by LiCl. Both the results of formaldehyde denatured agarose gel eleetrophoresis and ultraviolet spectrophotometer analysis showed high integrity and purity of RNA. So the quality of extracted RNA could meet the demand of most molecular biology experiments that require higher quality RNA.

Effect of Paclobutrazol plus Ethephon Treatment on Endogenous Hormones and Carbon and Nitrogen Nutrients in Litchi Variety ‘Feizixiao'

[Objective] This study aimed to investigate the effect of spraying the mixture of paclobutrazol and ethephon on the endogenous hormones and carbon and nitrogen nutrients in litchi variety ＇Feizixiao＇.[Method] [Result] The results showed that foliar spraying of the mixture of paclobutrazol and ethephon could effectively inhibit litchi variety ＇Feizixiao＇ to produce winter shoots,promote the flower bud differentiation and improve flower formation rate; meanwhile,this treatment could also increase the contents of ABA and ZR,and the ratios of ABA/IAA,ABA/GA3,ZR/IAA,ZR/GA3,and decrease the contents of IAA and GA3; additionally,it could increase the contents of soluble sugar,starch and total nitrogen,and raise C/N ratio,thus improving the flower formation rate.[Conclusion] Foliar spraying of the mixture of paclobutrazol and ethephon is an effective pathway for solving warmth damage to litchi.

Physiological Changes during the Process of Pericarp Browning in the Postharvest Litchi

[Objective] Pericarp browning in the postharvest litchi significantly reduced its commercial value and limited the expanding of litchi markets. Physiological changes during the process of pericarp browning were determined in order to identify the underlying mechanisms. [Method] Matured Feizixiao fruits were stored at 25 ℃ and 70%±5% relative humidity. The physiological changes happened in pericarp during storage were tested at an 8-hour interval. [Result] The fruit of Feizixiao (Litchi chinensis Sonn. cv Feizixiao) turned completely brown within 72 h after being harvested under the experimental conditions. Sharp increase of the browning index occurred from 48 to 64 hours after harvest (HAH). With the browning of pericarp,water content of the whole fruit and pericarp decreased continuingly. In contrast,there were no significant changes in the water content of pulp during the same period. MDA content,pH value and relative leakage rate of pericarp were increased during storage. Most of pigment contents including anthocyanin,flavonoid,phenols,chlorophyll a and total chlorophyll decreased. POD activity was initially increased in 32 HAH and then decreased afterwards. PPO activity was decreased continuously,while the activities of catalase and superoxide dismutase exhibited the pattern of 'increasing-decreasing-increasing' as the storage time progressed. Correlation,stepwise regression and path analyses showed that water loss of pericarp was the major factor of pericarp browning. Principal and cluster analyses showed that there were two stages of pericarp browning during the course of litchi storage. [Conclusion] Water status of pericarp was the most important factor affecting pericarp browning. The pericarp browning happened by stages,which was mainly determined by the water loss of pericarp.

Relationship Between Litchi Embryo Abortion and Phenolic Inhibitors

Phenolic inhibitors were preliminarily isolated from the normal and abortive litchi (Litchi chinensis Sonn.) ovules with a series of solvents, and then separated and purified by thin-layer chromatography (TLC), further isolated and identified with GC-MS, and finally checked with standards. p-Hydroxybenzoic acid (p-HBA) was isolated and identified from litchi ovules in this experiment for the first time. Determination of its biological activity showed that p-HBA was a very strong growth inhibitory substance. In abortive ovules, p-HBA content and IAA oxidase activity were much higher; IAA content was much lower than those in normal ovules (P<0.01). It is suggested that p-HBA may be involved in the regulation of litchi embryo development; high content of p-HBA may accelerate IAA oxidation and affect the balance of growth promoting and inhibitory substances, causing embryo abortion.

RAPD Analysis of Litchi chinensis Sonn.from Different Origins of China

[Objective] To lay the foundation for the classification and breeding of Litchi （Litchi chinensis Sonn.） through RAPD （Random Amplification Polymorphic DNA） analysis of the Litchi cultivars with different origins. [Method] 5 Litchi cultivars from Sichuan, Guangxi, Guangdong, Fujian and Hainan were used as experimental materials to extract genomic DNA by modified CTAB method. Twenty primers with well reproducibility were randomly selected to conduct RAPD amplification to analyze the polymorphism and genetic relationship of the five cultivars. [Result] The polymor- phism of the five Litchi cultivars was 61%, with the similarity coefficient of 0.571 4- 0.803 6. The similarity coefficient of those from Guangdong and Guangxi was the largest of 0.803 6, and from Sichuan and Hainan was the lowest of 0.571 4. The resolution and production of RAPD was significantly improved by appropriately pro- longing the ramp time from annealing to extension to 0.3℃/s. [Conclusion] This study provided theoretical basis for the classification and breeding of Litchi.

Advances in the Use of Exogenous Plant Growth Regulators on Litchi

In this paper,we reviewed the advances in the quality and functions of several exogenous plant growth regulators widely used on litchi,and in the applications of exogenous plant growth regulators on litchi production and fresh keeping of litchi,aiming at providing reference for future litchi production and improvement in litchi quality.

Comparative Analysis on Fruit Qualities of 7 Litchi Varieties from Vietnam

[Objective] The aim was to screen litchi varieties suitable for local production in Vietnam. [Method] The fruit botanical and quality characteristics of the seven litchi varieties introduced into Northern Mountainous Agriculture and Forestry Science Institute of Vietnam Academy of Agriculture Sciences were compared and analyzed. [Result] Three varieties with good general qualities including Lai Phu Ho,Thach Binh and Hung Long which were suitable to be cultivated in the local area were selected. In addition,Phu Dong was the available,early-maturing germplasm resource. [Conclusion] This research will provide reference for litchi production and breeding in northern mountainous area.

Agrobacterium tumefaciens-mediated transformation of embryogenic callus and CRISPR/Cas9-mediated genome editing in‘Feizixiao'litchi

Litchi(Litchi chinensis Sonn.)is a type of commercially prevalent subtropical and tropical fruit.Since litchi has a highly heterozygous genetic background and a long reproductive cycle,conventional breeding methods(such as hybridization)have limited ability to nurture new litchi cultivars.Here,an efficient and stable Agrobacterium tumefaciens-mediated genetic transformation of embryogenic callus was established in‘Feizixiao’litchi.Transgenic materials were verified using polymerase chain reaction(PCR)analysis,β-glucuronidase(GUS)assay,and green fluorescent protein(GFP)assay.To implement the technology of the Clustered Regularly Interspaced Short Palindromic Repeats(CRISPR)/associated protein 9(CRISPR/Cas9)technology in‘Feizixiao’litchi and verify the validity of these transformation systems,the litchi polyphenol oxidase gene(LcPPO,JF926153)was knocked out.Various categories of mutations,covering base insertions,deletions,and substitutions,were found in transgenic materials via sequence analysis.The transformation system achieved high feasibility and efficiency,and the system of CRISPR/Cas9 was successfully employed to edit genes in‘Feizixiao’litchi.This work provides an essential foundation for investigating the functions of genes and accelerating litchi genetic improvement.