High-Performance Photodynamic Therapy of Tongue Squamous Cell Carcinoma with Multifunctional Nano-Verteporfin.

Background: The photodynamic therapy (PDT) showed promising potential in treating tongue squamous cell carcinoma (TSCC). The Food and Drug Administration approved Verteporfin (Ver) is a powerful alternative in this field for its penetrating power and high production of reactive oxygen species (ROS). However, its applications in the treatment of TSCC are still rare. Methods: Ver was loaded onto Poly (lactic-co-glycolic acid) (PLGA) nanoparticles, followed by the modification with RGD peptide as the ligand. The nanostructured was named as RPV. In vitro assessments were conducted to evaluate the cytotoxicity of RPV through the Live/Dead assay analysis and Cell Counting Kit-8 (CCK-8) assay. Using the reactive oxygen species assay kit, the potential for inducing targeted tumor cell death upon laser irradiation by promoting ROS production was investigated. In vivo experiments involved with the biological distribution of RPV, the administration with RPV followed by laser irradiation, and the measurement of the tumor volumes. Immunohistochemical analysis was used to detect the Ki-67 expression, and apoptosis induced by RPV-treated group. Systemic toxicity was evaluated through hematoxylin-eosin staining and blood routine analysis. Real-time monitoring was employed to track RPV accumulation at tumor sites. Results: The in vitro assessments demonstrated the low cytotoxicity of RPV and indicated its potential for targeted killing TSCC cells under laser irradiation. In vivo experiments revealed significant tumor growth inhibition with RPV treatment and laser irradiation. Immunohistochemical analysis showed a notable decrease in Ki-67 expression, suggesting the effective suppression of cell proliferation, and TUNEL assay indicated the increased apoptosis in the RPV-treated group. Pathological examination and blood routine analysis revealed no significant systemic toxicity. Real-time monitoring exhibited selective accumulation of RPV at tumor sites. Conclusion: The findings collectively suggest that RPV holds promise as a safe and effective therapeutic strategy for TSCC, offering a combination of targeted drug delivery with photodynamic therapy.

Nano-Photosensitizer Directed Targeted Phototherapy Effective Against Oral Cancer in Animal Model.

Background: Photodynamic therapy (PDT) has emerged as a promising strategy for oral cancer treatment. Verteporfin is a powerful photosensitizer and widely used in the treatment of macular degeneration. However, rare work has reported its potential in the treatment of oral cancer. Methods: In this study, we introduce an innovative approach of nano-photosensitizer based on Verteporfin, which was prepared by utilizing macrophage membrane to coat Verteporfin-loaded zeolitic imidazolate framework 8 (ZIF-8) for effective photodynamic therapy against oral cancer. Nanoparticle characteristics were assessed including size, zeta potential, and PDI. Cellular uptake studies were conducted using CAL-27 cells. Furthermore, inhibitory effects in both in vitro and in vivo settings were observed, ensuring biosafety. Assessment of anticancer efficacy involved tumor volume measurement, histological analyses, and immunohistochemical staining. Results: In vitro experiments indicated that the nano-photosensitizer showed efficient cellular uptake in the oral cancer cells. Upon the laser irradiation, the nano-photosensitizer induced the generation of reactive oxygen species (ROS), leading to cancer cell apoptosis. The in vivo experiments indicated that the coating with cell membranes enhanced the circulation time of nano-photosensitizer. Moreover, the specificity of the nano-photosensitizer to the cancer cells was also improved by the cell membrane-camouflaged structure in the tumor-bearing mouse model, which inhibited the tumor growth significantly by the photodynamic effect in the presence of laser irradiation. Conclusion: Overall, our findings demonstrate the potential of macrophage membrane-coated ZIF-8-based nanoparticles loaded with Verteporfin for effective photodynamic therapy in oral cancer treatment. This nano-system holds promise for synergistic cancer therapy by combining the cytotoxic effects of PDT with the activation of the immune system, providing a novel therapeutic strategy for combating cancer.

Apoptotic bodies: bioactive treasure left behind by the dying cells with robust diagnostic and therapeutic application potentials.

Apoptosis, a form of programmed cell death, is essential for growth and tissue homeostasis. Apoptotic bodies (ApoBDs) are a form of extracellular vesicles (EVs) released by dying cells in the last stage of apoptosis and were previously regarded as debris of dead cells. Recent studies unraveled that ApoBDs are not cell debris but the bioactive treasure left behind by the dying cells with an important role in intercellular communications related to human health and various diseases. Defective clearance of ApoBDs and infected-cells-derived ApoBDs are possible etiology of some diseases. Therefore, it is necessary to explore the function and mechanism of the action of ApoBDs in different physiological and pathological conditions. Recent advances in ApoBDs have elucidated the immunomodulatory, virus removal, vascular protection, tissue regenerative, and disease diagnostic potential of ApoBDs. Moreover, ApoBDs can be used as drug carriers enhancing drug stability, cellular uptake, and targeted therapy efficacy. These reports from the literature indicate that ApoBDs hold promising potential for diagnosis, prognosis, and treatment of various diseases, including cancer, systemic inflammatory diseases, cardiovascular diseases, and tissue regeneration. This review summarizes the recent advances in ApoBDs-related research and discusses the role of ApoBDs in health and diseases as well as the challenges and prospects of ApoBDs-based diagnostic and therapeutic applications.

Circular RNA PDK1 targets miR-4731-5p to enhance TNXB expression in ligamentum flavum hypertrophy.

Hypertrophic ligamentum flavum (LF) is a main factor responsible for lumbar spinal stenosis (LSS); however, the exact mechanisms of the pathogenesis of these processes remain unknown. This study aimed to elucidate whether circular RNAs and microRNAs regulate the pathogenesis of LF and LSS, especially focusing on circPDK1 (hsa_circ_0057105), a circRNA targeting pyruvate dehydrogenase kinase 1 and differentially expressed in LF tissues between lumbar disk herniation and LSS patients. The circPDK1/miR-4731 and miR-4731/TNXB (Tenascin XB) interactions were predicted and validated by luciferase reporter assay. Colony formation, wound-healing, and MTT assays were used for estimating cell proliferation and migration. Protein expression levels were evaluated using Western blotting. TNXB expression was verified using immunohistochemistry (IHC). Overexpressing circPDK1 promoted the proliferation, migration, and expression of fibrosis-related protein (alpha smooth muscle actin (α-SMA), lysyl oxidase like 2 (LOXL2), Collagen I, matrix metalloproteinase-2 (MMP-2) and TNXB) in LF whereas miR-4731-5p showed opposite effects. The expression of TNXB was promoted by circPDK1; contrary results were observed with miR-4731-5p. Co-overexpression of miR-4731-5p partially reversed the proliferative and fibrosis-prompting effects of circPDK1 or TNXB. The circPDK1-miR-4731-TNXB pathway may be proposed as a regulatory axis in LF hypertrophy, which might shed light on in-depth research of LSS, as well as providing a novel therapeutic target for LF hypertrophy-induced LSS.

Cannabidiol Rescues TNF-α-Inhibited Proliferation, Migration, and Osteogenic/Odontogenic Differentiation of Dental Pulp Stem Cells.

Strategies to promote dental pulp stem cells (DPSCs) functions including proliferation, migration, pro-angiogenic effects, and odontogenic/osteogenic differentiation are in urgent need to restore pulpitis-damaged dentin/pulp regeneration and DPSCs-based bone tissue engineering applications. Cannabidiol (CBD), an active component of Cannabis sativa has shown anti-inflammation, chemotactic, anti-microbial, and tissue regenerative potentials. Based on these facts, this study aimed to analyze the effect of CBD on DPSCs proliferation, migration, and osteogenic/odontogenic differentiation in basal and inflammatory conditions. Highly pure DPSCs with characteristics of mesenchymal stem cells (MSCs) were successfully isolated, as indicated by the results of flowcytometry and multi-lineage (osteogenic, adipogenic, and chondrogenic) differentiation potentials. Among the concentration tested (0.1-12.5 µM), CBD (2.5 µM) showed the highest anabolic effect on the proliferation and osteogenic/odontogenic differentiation of DPSCs. Pro-angiogenic growth factor VEGF mRNA expression was robustly higher in CBD-treated DPSCs. CBD also prompted the migration of DPSCs and CBD receptor CB1 and CB2 expression in DPSCs. TNF-α inhibited the viability, migration, and osteogenic/odontogenic differentiation of DPSCs and CBD reversed these effects. CBD alleviated the TNF-α-upregulated expression of pro-inflammatory cytokines TNF-α, interleukin (IL)-1ß, and IL-6 in DPSCs. In conclusion, our results indicate the possible application of CBD on DPSCs-based dentin/pulp and bone regeneration.

Synergistic effect of glutathione and IgG4 in immune evasion and the implication for cancer immunotherapy.

BACKGROUND: We recently reported a novel IgG4-centered immune evasion mechanism in cancer, and this was achieved mostly through the Fc-Fc reaction of increased IgG4 to cancer-bound IgG in cancer microenvironment. The mechanism was suggested to be related to cancer hyperprogressive disease (HPD) which is a side-effect often associated to IgG4 subtype PD-1 antibody immunotherapy. HPD was reported to occur in cancers with certain mutated genes including KRAS and such mutations are often associated to glutathione (GSH) synthesis. Therefore, we hypothesize that IgG4 and GSH may play a synergistic role in local immunosuppression of cancer. METHODS: Quantitatively analyzed the distribution and abundance of GSH and IgG4 in human cancer samples with ELISA and immunohistochemistry. The interactions between GSH and IgG4 were examined with Electrophoresis and Western Blot. The synergistic effects of the two on classic immune responses were investigated in vitro. The combined effects were also tested in a lung cancer model and a skin graft model in mice. RESULTS: We detected significant increases of both GSH and IgG4 in the microenvironment of lung cancer, esophageal cancer, and colon cancer tissues. GSH disrupted the disulfide bond of IgG4 heavy chain and enhanced IgG4's ability of Fc-Fc reaction to immobilized IgG subtypes. Combined administration of IgG4 and GSH augmented the inhibitory effect of IgG4 on the classic ADCC, ADCP, and CDC reactions. Local administration of IgG4/GSH achieved the most obvious effect of accelerating cancer growth in the mouse lung cancer model. The same combination prolonged the survival of skin grafts between two different strains of mouse. In both models, immune cells and several cytokines were found to shift to the state of immune tolerance. CONCLUSION: Combined application of GSH and IgG4 can promote tumor growth and protect skin graft. The mechanism may be achieved through the effect of the Fc-Fc reaction between IgG4 and other tissue-bound IgG subtypes resulting in local immunosuppression. This reaction was facilitated by increased GSH to dissociate the two heavy chains of IgG4 Fc fragment at its disulfide bonds. Our findings unveiled the interaction between the redox system and the immune systems in cancer microenvironment. It offers a sensible explanation for HPD and provides new possibilities for manipulating this mechanism for cancer immunotherapy.

Effects of Juvenile Hormone Analog and Days after Emergence on the Reproduction of Oriental Armyworm, Mythimna separata (Lepidoptera: Noctuidae) Populations.

Mythimna separata (Walker) is a main cereal crop pest that causes extensive damage to the world grain production. The effects of juvenile hormone on M. separata populations remain poorly understood. Here, we explored how JH analog (JHA) affected reproductive traits of both migrant and resident populations in this pest. Our results showed that the influence of JHA treatment on reproduction depended on adult age (days after emergence) of exposure to JHA and populations. Exposure of M. separata residents to JHA (methoprene) on day 1 and day 2 after adult emergence significantly shortened the pre-oviposition period, but increased the lifetime fecundity, mating frequency and grade of ovarian development compared to the controls. However, M. separata migrants exposed to JHA only on day 1 facilitated their reproduction, resulting in a reduction in the pre-oviposition period but an increase in lifetime fecundity, mating frequency and grade of ovarian development. In addition, exposure to JHA from day 2 to day 4 did not significantly affect the ovarian and reproductive development in both migrant and resident populations. These results indicated that the first two days after adult emergence were the sensitive period for residents. In contrast, only the first day after adult emergence was the sensitive stage for migrants. Our findings will contribute to a better understanding of JHA function on M. separata populations.

Human Umbilical Cord Mesenchymal Stem Cells Encapsulated with Pluronic F-127 Enhance the Regeneration and Angiogenesis of Thin Endometrium in Rat via Local IL-1ß Stimulation.

Thin endometrium (< 7 mm) could cause low clinical pregnancy, reduced live birth, increased spontaneous abortion, and decreased birth weight. However, the treatments for thin endometrium have not been well developed. In this study, we aim to determine the role of Pluronic F-127 (PF-127) encapsulation of human umbilical cord mesenchymal stem cells (hUC-MSCs) in the regeneration of thin endometrium and its underlying mechanism. Thin endometrium rat model was created by infusion of 95% ethanol. Thin endometrium modeled rat uterus were treated with saline, hUC-MSCs, PF-127, or hUC-MSCs plus PF-127 separately. Regenerated rat uterus was measured for gene expression levels of angiogenesis factors and histological morphology. Angiogenesis capacity of interleukin-1 beta (IL-1ß)-primed hUC-MSCs was monitored via quantitative polymerase chain reaction (q-PCR), Luminex assay, and tube formation assay. Decreased endometrium thickness and gland number and increased inflammatory factor IL-1ß were achieved in the thin endometrium rat model. Embedding of hUC-MSCs with PF-127 could prolong the hUC-MSCs retaining, which could further enhance endometrium thickness and gland number in the thin endometrium rat model via increasing angiogenesis capacity. Conditional medium derived from IL-1ß-primed hUC-MSCs increased the concentration of angiogenesis factors (basic fibroblast growth factor (bFGF), vascular endothelial growth factors (VEGF), and hepatocyte growth factor (HGF)). Improvement in the thickness, number of glands, and newly generated blood vessels could be achieved by uterus endometrium treatment with PF-127 and hUC-MSCs transplantation. Local IL-1ß stimulation-primed hUC-MSCs promoted the release of angiogenesis factors and may play a vital role on thin endometrium regeneration.

Building the Chordata Olfactory Receptor Database using more than 400,000 receptors annotated by Genome2OR.

Olfactory receptors are poorly annotated for most genome-sequenced chordates. To address this deficiency, we developed a nhmmer-based olfactory receptor annotation tool Genome2OR ( https://github.com/ToHanwei/Genome2OR.git ), and used it to process 1,695 sequenced chordate genomes in the NCBI Assembly database as of January, 2021. In total, 765,248 olfactory receptor genes were annotated, with 404,426 functional genes and 360,822 pseudogenes, which represents a four-fold increase in the number of annotated olfactory receptors. Based on the annotation data, we built a database called Chordata Olfactory Receptor Database (CORD, https://cord.ihuman.shanghaitech.edu.cn ) for archiving, analysing and disseminating the data. Beyond the primary data, we offer derivative information, including pictures of species, cross references to public databases, structural models, sequence similarity networks and sequence profiles in the CORD. Furthermore, we did brief analyses on these receptors, including building a huge protein sequence similarity network covering all receptors in the database, and clustering them into 20 communities, classifying the 20 communities into three categories based on their presences/absences in ray-finned fish and/or lobe-finned fish. We infer that olfactory receptors should have unique activation and desensitization mechanisms by analysing their sequences and structural models. We believe the CORD can benefit the researchers and the general public who are interested in olfaction.

The Emerging Role of Plant-Derived Exosomes-Like Nanoparticles in Immune Regulation and Periodontitis Treatment.

Periodontitis is an infectious oral disease, which leads to the destruction of periodontal tissues and tooth loss. Although the treatment of periodontitis has improved recently, the effective treatment of periodontitis and the periodontitis-affected periodontal tissues is still a challenge. Therefore, it is urgent to explore new therapeutic strategies for periodontitis. Natural products show anti-microbial, anti-inflammatory, anti-oxidant and bone protective effects to periodontitis and most of these natural products are safe and cost-effective. Among these, the plant-derived exosome-like nanoparticles (PELNs), a type of natural nanocarriers repleted with lipids, proteins, RNAs, and other active molecules, show the ability to enter mammalian cells and regulate cellular activities. Reports from the literature indicate the great potential of PELNs in the regulation of immune functions, inflammation, microbiome, and tissue regeneration. Moreover, PELNs can also be used as drug carriers to enhance drug stability and cellular uptake in vivo. Since regulation of immune function, inflammation, microbiome, and tissue regeneration are the key phenomena usually targeted during periodontitis treatment, the PELNs hold the promising potential for periodontitis treatment. This review summarizes the recent advances in PELNs-related research that are related to the treatment of periodontitis and regeneration of periodontitis-destructed tissues and the underlying mechanisms. We also discuss the existing challenges and prospects of the application of PELNs-based therapeutic approaches for periodontitis treatment.

Complete Genome Sequencing and Comparative Analysis of the Clinically-Derived Apiotrichum mycotoxinivorans Strain GMU1709.

Over the past decade, Apiotrichum mycotoxinivorans has been recognized globally as a source of opportunistic infections. It is a yeast-like fungus, and its association as an uncommon pulmonary pathogen with cystic fibrosis patients has been previously reported. Immunocompromised patients are at the highest risk of A. mycotoxinivorans infections. Therefore, to investigate the genetic basis for the pathogenicity of A. mycotoxinivorans, we performed whole-genome sequencing and comparative genomic analysis of A. mycotoxinivorans GMU1709 that was isolated from sputum specimens of a pneumonia patient receiving cardiac repair surgery. The assembly of Oxford Nanopore reads from the GMU1709 strain and its subsequent correction using Illumina paired-end reads yielded a high-quality complete genome with a genome size of 30.5 Mb in length, which comprised six chromosomes and one mitochondrion. Subsequently, 8,066 protein-coding genes were predicted based on multiple pieces of evidence, including transcriptomes. Phylogenomic analysis indicated that A. mycotoxinivorans exhibited the closest evolutionary affinity to A. veenhuisii, and both the A. mycotoxinivorans strains and the formerly Trichosporon cutaneum ACCC 20271 strain occupied the same phylogenetic position. Further comparative analysis supported that the ACCC 20271 strain belonged to A. mycotoxinivorans. Comparisons of three A. mycotoxinivorans strains indicated that the differences between clinical and non-clinical strains in pathogenicity and drug resistance may be little or none. Based on the comparisons with strains of other species in the Trichosporonaceae family, we identified potential key genetic factors associated with A. mycotoxinivorans infection or pathogenicity. In addition, we also deduced that A. mycotoxinivorans had great potential to inactivate some antibiotics (e.g., tetracycline), which may affect the efficacy of these drugs in co-infection. In general, our analyses provide a better understanding of the classification and phylogeny of the Trichosporonaceae family, uncover the underlying genetic basis of A. mycotoxinivorans infections and associated drug resistance, and provide clues into potential targets for further research and the therapeutic intervention of infections.

Memantine Promotes Bactericidal Effect of Neutrophils Against Infection with Pseudomonas aeruginosa and Its Drug-Resistant Strain, by Improving Reactive Oxygen Species Generation.

Pseudomonas aeruginosa is an opportunistic pathogen, which usually presents multiple antibiotic resistance. Host-directed therapy involves modulating the host defense system and the interplay between innate and adaptive immunity is a new strategy for designing anti-infection drugs. Memantine (MEM), a drug used to treat Alzheimer's disease, has a good inhibitory effect on neonatal mice with Escherichia coli-associated bacteremia and meningitis; however, the inhibitory effect and mechanisms of MEM against P. aeruginosa infection remain unclear. Here, we investigated whether MEM could inhibit P. aeruginosa infection and explored the potential mechanisms. MEM significantly promoted the bactericidal effect of neutrophils against P. aeruginosa and its drug-resistant strain. The combination index of MEM and amikacin (AMK) was <1. In vivo experiments showed that the bacteremia and inflammation severities in the MEM-treated group were less than those in the untreated group, and the bacterial load in the organs was significantly less than that in the control group. Combining MEM with the reactive oxygen species (ROS) inhibitor, N-acetyl-l-cysteine, weakened the anti-infective effect of MEM. MEM increased the expression of NADPH p67phox and promoted neutrophilic ROS production. Deleting the p67phox gene significantly weakened the effects of MEM on ROS generation and improving bactericidal effect of neutrophils. In conclusion, MEM promoted the bactericidal effect of neutrophils against P. aeruginosa and its drug-resistant strain, and had a synergistic antibacterial effect when combined with AMK. MEM may exert its anti-infective effects by promoting neutrophilic bactericidal activity via increasing the expression level of p67phox and further stimulating ROS generation.

Ligands of Adrenergic Receptors: A Structural Point of View.

Adrenergic receptors are G protein-coupled receptors for epinephrine and norepinephrine. They are targets of many drugs for various conditions, including treatment of hypertension, hypotension, and asthma. Adrenergic receptors are intensively studied in structural biology, displayed for binding poses of different types of ligands. Here, we summarized molecular mechanisms of ligand recognition and receptor activation exhibited by structure. We also reviewed recent advances in structure-based ligand discovery against adrenergic receptors.

Discovery and antibacterial study of potential PPK1 inhibitors against uropathogenic E. coli.

Novel antibacterial agents are urgently needed to address the infections caused by multi-drug resistant bacteria. Urinary tract infections are common infectious diseases in clinical. Most of these infections are caused by drug-resistant uropathogenic Escherichia coli. PPK1 is an essential kinase for bacterial motility, biofilm formation, quorum sensing, and virulence factors in the expression of uropathogenic E. coli. In the present study, two small molecules potentially targeting PPK1 were discovered through virtual screening and biological assays. The in vitro and in vivo results suggested that the interaction of these compounds with PPK1 can disrupt biofilm formation of uropathogenic E. coli and reduce invasive ability and resistance to oxidative stress of this strain. Moreover, the compounds exhibit good antibacterial bacterial activity in the mice with urinary tract infection. Taken together, our findings could provide a new chemotype for the development of antibacterials targeting PPK1.

Transcriptome Analysis of Two Strains of Proteus mirabilis with Swarming Migration Deficiency Isolated from Patients with Urinary Tract Infection.

Two rare strains of Proteus mirabilis with swarming migration deficiency were isolated from urine samples of two patients with urinary tract infections and were named as G121 and G137. Migration experiments showed that P. mirabilis HI4320 had typical migration on blood agar, while G121 and G137 had significantly weakened migration ability. Results of adhesion tests showed that the adhesion ability of G121 and G137 to the bladder epithelial cell line 5637 was significantly reduced. High-throughput sequencing and alignment analysis of the transcriptomes of the three P. mirabilis strains were conducted, with P. mirabilis HI4320 as the reference strain. Reverse transcription quantitative PCR (RT-qPCR) was used to verify differentially expressed genes. Results of transcriptome analysis and RT-qPCR showed that, compared to the HI4320 strain, genes related to flagellum and fimbria formation, dicarboxylate transport, and cystathionine and anthranilate metabolism were down-regulated in G121 and G137, while genes related to iron transport, molybdenum metabolism, and metalloprotease were up-regulated, suggesting that these genes may be involved in the migration ability and epithelial cell adhesion ability of P. mirabilis. These results provide important insight to the search for virulence genes and the screening of new antibacterial targets for P. mirabilis.

Expression profiling of lncRNAs and mRNAs reveals regulation of muscle growth in the Pacific abalone, Haliotis discus hannai.

Long non-coding RNAs (lncRNAs) are known to play a major role in the epigenetic regulation of muscle development. Unfortunately there is little understanding of the mechanisms with which they regulate muscle growth in abalone. Therefore, we used RNA-seq to study the muscle transcriptomes of six Haliotis discus hannai specimens: three large (L_HD group) and three small (S_HD group). We identified 2463 lncRNAs in abalone muscle belonging to two subtypes: 160 anti-sense lncRNAs and 2303 intergenic lncRNAs (lincRNAs). In the L_HD group, we identified 204 significantly differentially expressed lncRNAs (55 upregulated and 149 downregulated), and 2268 significantly differentially expressed mRNAs (994 upregulated and 1274 downregulated), as compared to the S_HD group. The bioinformatics analysis indicated that lncRNAs were relate to cell growth, regulation of growth, MAPK signaling pathway, TGF-ß signaling pathway, PI3K-Akt and insulin signaling pathway, which involved in regulating muscle growth. These findings contribute to understanding the possible regulatory mechanisms of muscle growth in Pacific abalone.

OsPT4 Contributes to Arsenate Uptake and Transport in Rice.

Arsenic (As) is toxic to organisms, and elevated As accumulation in rice (Oryza sativa) grain may pose a significant health risk to humans. The predominant form of As in soil under aerobic conditions is As(V), which has a chemical structure similar to that of PO43-. Rice roots take up As(V) by phosphate (Pi) transporters, such as OsPT1 and OsPT8. In the present study, we investigated the contribution of OsPT4, belonging to the Pht1 family, on rice As(V) uptake and transport. We determined the mRNA amounts of OsPTs in rice seedlings, and expressions of OsPT1, OsPT4, and OsPT8 were up-regulated under As(V) conditions. OsPT4-overexpressing plants were obtained to examine the As (V) transport activity of OsPT4 in rice. When transgenic rice grew in hydroponic culture with 25 and 50 µM As(V), the plants showed sensitivity to As(V) stress with aboveground parts showing delayed growth and the roots stunted. The OsPT4 CRISPR lines showed the opposite phenotype. When plants were grown in 5 µM As(V) solution for 7 days, the As accumulation of OsPT4-overexpressing plants increased up to twice in roots and shoots. Furthermore, the arsenate uptake rates of OsPT4-overexpressing lines were higher compared with wild type. The Vmax of As(V) uptake in OsPT4-overexpressing plants increased 23-45% compared with Nipponbare. In the flooded soil, the As accumulation of OsPT4-overexpressing plants increased 40-66% and 22-30% in straw and grain, respectively. While in OsPT4-cr plants As accumulation in roots decreased 17-30% compared with Nipponbare. Therefore, the present study indicates that OsPT4 is involved in As(V) uptake and transport and could be a good candidate gene to generate low As-accumulating rice.