Regulation of the PD-1/PD-L1 Axis and NK Cell Dysfunction by Exosomal miR-552-5p in Gastric Cancer.

OBJECTIVE: NK cells play a vital role in tumor immune resistance. Various factors affect NK cell activity. While NK cell dysfunction has been observed in numerous malignancies, the underlying mechanisms in gastric cancer remain unclear. METHOD: Flow cytometry was used to identify the phenotypic distribution and expression of activated receptors on NK cells. ELISA was used to determine the expression of cytokines. We examined the expression of NK cell-related genes and explored their association with survival and prognosis. Additionally, we conducted PCR detection of miR-552-5p expression levels in plasma exosomes of patients and investigated its correlation with phenotypic distribution and activated receptors. We used flow cytometry and ELISA to verify the role of miR-552-5p in NK cell dysfunction. Furthermore, we investigated the potential role of PD-1/PD-L1 in regulating NK cell dysfunction in patients' cells. RESULTS: We observed a significant decrease in the percentage of NKG2D and NKp30 and IFN-γ and TNF-α in patients than in healthy volunteers. Patients with low levels of CD56, CD16, NKG2D, and NKP46 exhibited poorer survival prognoses. Moreover, increased expression levels of plasma exosomal miR-552-5p in patients were negatively associated with NK cell phenotypic distribution and activated receptor expression. MiR-552-5p downregulated the secretion of perforin, granzyme, and IFN-γ as well as the expression of NKp30, NKp46, and NKG2D. Additionally, it suppressed the cytotoxicity of NK cells. The inhibitory effect of miR-552-5p, on NK cell function was reversed when anti-PD-L1 antibodies were used. CONCLUSION: Exosomal miR-552-5p targets the PD-1/PD-L1 axis, leading to impaired NK cell function.

PST-Diff: Achieving High-consistency Stain Transfer by Diffusion Models with Pathological and Structural Constraints.

Histopathological examinations heavily rely on hematoxylin and eosin (HE) and immunohistochemistry (IHC) staining. IHC staining can offer more accurate diagnostic details but it brings significant financial and time costs. Furthermore, either re-staining HE-stained slides or using adjacent slides for IHC may compromise the accuracy of pathological diagnosis due to information loss. To address these challenges, we develop PST-Diff, a method for generating virtual IHC images from HE images based on diffusion models, which allows pathologists to simultaneously view multiple staining results from the same tissue slide. To maintain the pathological consistency of the stain transfer, we propose the asymmetric attention mechanism (AAM) and latent transfer (LT) module in PST-Diff. Specifically, the AAM can retain more local pathological information of the source domain images through the design of asymmetric attention mechanisms, while ensuring the model's flexibility in generating virtual stained images that highly confirm to the target domain. Subsequently, the LT module transfers the implicit representations across different domains, effectively alleviating the bias introduced by direct connection and further enhancing the pathological consistency of PST-Diff. Furthermore, to maintain the structural consistency of the stain transfer, the conditional frequency guidance (CFG) module is proposed to precisely control image generation and preserve structural details according to the frequency recovery process. To conclude, the pathological and structural consistency constraints provide PST-Diff with effectiveness and superior generalization in generating stable and functionally pathological IHC images with the best evaluation score. In general, PST-Diff offers prospective application in clinical virtual staining and pathological image analysis.

Chromosome-level genome assembly of the bethylid ectoparasitoid wasp Sclerodermus sp. 'alternatusi'.

The Bethylidae are the most diverse of Hymenoptera chrysidoid families. As external parasitoids, the bethylids have been widely adopted as biocontrol agents to control insect pests worldwide. Thus far, the genomic information of the family Bethylidae has not been reported yet. In this study, we crystallized into a high-quality chromosome-level genome of ant-like bethylid wasps Sclerodermus sp. 'alternatusi' (Hymenoptera: Bethylidae) using PacBio sequencing as well as Hi-C technology. The assembled S. alternatusi genome was 162.30 Mb in size with a contig N50 size of 3.83 Mb and scaffold N50 size of 11.10 Mb. Totally, 92.85% assembled sequences anchored to 15 pseudo-chromosomes. A total of 10,204 protein-coding genes were annotated, and 23.01 Mb repetitive sequences occupying 14.17% of genome were pinpointed. The BUSCO results showed that 97.9% of the complete core Insecta genes were identified in the genome, while 97.1% in the gene sets. The high-quality genome of S. alternatusi will not only provide valuable genomic information, but also show insights into parasitoid wasp evolution and bio-control application in future studies.

Salivary proteins NlSP5 and NlSP7 are required for optimal feeding and fitness of the brown planthopper, Nilaparvata lugens.

BACKGROUND: Saliva has a crucial role in determining the compatibility between piercing-sucking insects and their hosts. The brown planthopper (BPH) Nilaparvata lugens, a notorious pest of rice in East and Southeast Asia, secretes gelling and watery saliva when feeding on rice sap. Nlsalivap-5 (NlSP5) and Nlsalivap-7 (NlSP7) were identified as potential planthopper-specific gelling saliva components, but their biological functions remain unknown. RESULTS: Here, we showed by transcriptomic analyses that NlSP5 and NlSP7 were biasedly expressed in the salivary glands of BPHs. Using the clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9-mediated genome-editing system, we constructed NlSP5 and NlSP7 homozygous mutants (NlSP5-/- and NlSP7-/-). Electrical penetration graph assay showed that NlSP5-/- and NlSP7-/- mutants exhibited abnormal probing and feeding behaviors. Bioassays revealed that the loss-of-function of NlSP5 and NlSP7 significantly reduced the fitness of BPHs, with extended developmental duration, shortened lifespan, reduced weight, and impaired fecundity and hatching rates. CONCLUSION: These findings deepen our understanding of the BPH-host interaction and may provide potential targets for the management of rice planthoppers. © 2024 Society of Chemical Industry.

Investigation of the emergency water supply schemes for youkou groundwater source field in Nanchang using a simulation-optimization model.

To enhance the resilience of Nanchang's water supply system and ensure a dependable emergency water supply. Taking youkou emergency groundwater source field as an example, a flow simulation model was developed through an analysis of the hydrogeological conditions in the study area. Additionally, an optimization model based on the genetic algorithm (GA) technique was constructed and integrated into the flow simulation model. Subsequently, various water supply schemes were simulated with the minimum cost of groundwater extraction as the objective function. The results show that the values of the objective function were reduced by 4.92%, 15.67%, and 42.35% for the three different optimization schemes, namely pumping rates, joint pumping rates and the number of wells, and joint pumping rates, number of wells and well location. Ultimately, the optimal emergency water supply scheme was determined by considering a comprehensive range of factors. These factors encompassed considerations such as the area of the water level depression funnel, the dewatering thickness of the aquifer and the recovery of the groundwater level. The practice shows that the simulation-optimization model could effectively simulate complex groundwater flow systems, meeting the objective function and constraints toachieve the optimal exploitation scheme.

Tumor cell SPTBN1 inhibits M2 polarization of macrophages by suppressing CXCL1 expression.

Tumor-associated macrophages (TAMs) are the most abundant immune cells in the tumor microenvironment, and the M2-type TAMs can promote tumor growth, invasion and angiogenesis, and suppress antitumor immune responses. It has been reported that spectrin beta, non-erythrocytic 1 (SPTBN1) may inhibit the infiltration of macrophages in Sptbn1+/-  mouse liver, but whether tumor SPTBN1 affects TAMs polarization remains unclear. This study investigated the effect and mechanism of tumor cell SPTBN1 on polarization and migration of TAMs in hepatoma and breast cancer. By analyzing tumor immune databases, we found a negative correlation between SPTBN1 and abundance of macrophages and myeloid-derived suppressor cells (MDSCs) in the tumor microenvironment. By reverse transcription-quantitative real-time PCR assays and cell migration assays, the migration and M2 polarization of macrophages were enhanced by the culture medium from hepatocellular carcinoma cell line PLC/PRF/5, SNU449, and breast cancer cell line MDA-MB-231 with SPTBN1 suppression, which could be reversed by CXCL1 neutralizing antibody MAB275. Meanwhile, the ability of migration and colony formation of PLC/PRF/5, SNU449, and MDA-MB-231 cells were promoted when coculture with M2 macrophages. We also found that SPTBN1 regulated CXCL1 through p65 by cytoplasmic-nuclear protein isolation experiments and ChIP-qPCR. Our data suggest that tumor cell SPTBN1 inhibits migration and M2-type polarization of TAMs by reducing the expression and secretion of CXCL1 via inhibiting p65 nuclear localization.

Identifying pathogenicity-related genes in the pathogen Colletotrichum magnum causing watermelon anthracnose disease via T-DNA insertion mutagenesis.

Fruit rot caused by Colletotrichum magnum is a crucial watermelon disease threatening the production and quality. To understand the pathogenic mechanism of C. magnum, we optimized the Agrobacterium tumefaciens-mediated transformation system (ATMT) for genetic transformation of C. magnum. The transformation efficiency of ATMT was an average of around 245 transformants per 100 million conidia. Southern blot analysis indicated that approximately 75% of the mutants contained a single copy of T-DNA. Pathogenicity test revealed that three mutants completely lost pathogenicity. The T-DNA integration sites (TISs) of three mutants were Identified. In mutant Cm699, the TISs were found in the intron region of the gene, which encoded a protein containing AP-2 complex subunit σ, and simultaneous gene deletions were observed. Two deleted genes encoded the transcription initiation protein SPT3 and a hypothetical protein, respectively. In mutant Cm854, the TISs were found in the 5'-flanking regions of a gene that was similar to the MYO5 encoding Myosin I of Pyricularia oryzae (78%). In mutant Cm1078, the T-DNA was integrated into the exon regions of two adjacent genes. One was 5'-3' exoribonuclease 1 encoding gene while the other encoded a WD-repeat protein retinoblastoma binding protein 4, the homolog of the MSl1 of Saccharomyces cerevisiae.

FoxO and rotund form a binding complex governing wing polyphenism in planthoppers.

Wing polyphenism is found in a variety of insects and offers an attractive model system for studying the evolutionary significance of dispersal. The Forkhead box O (FoxO) transcription factor (TF) acts as a wing-morph switch that directs wing buds developing into long-winged (LW) or short-winged morphs in wing-dimorphic planthoppers, yet the regulatory mechanism of the FoxO module remains elusive. Here, we identified the zinc finger TF rotund as a potential wing-morph regulator via transcriptomic analysis and phenotypic screening in the brown plathopper, Nilaparvata lugens. RNA interference-mediated knockdown of rotund antagonized the LW development derived from in the context of FoxO depletion or the activation of the insulin/insulin-like growth factor signaling cascade, reversing long wings into intermediate wings. In vitro binding assays indicated that rotund physically binds to FoxO to form the FoxO combinatorial code. These findings broaden our understanding of the complexity of transcriptional regulation governing wing polyphenism in insects.

Cardiac-specific BACH1 ablation attenuates pathological cardiac hypertrophy by inhibiting the Ang II type 1 receptor expression and the Ca2+/CaMKII pathway.

AIMS: BACH1 is up-regulated in hypertrophic hearts, but its function in cardiac hypertrophy remains largely unknown. This research investigates the function and mechanisms of BACH1 in the regulation of cardiac hypertrophy. METHODS AND RESULTS: Male cardiac-specific BACH1 knockout mice or cardiac-specific BACH1 transgenic (BACH1-Tg) mice and their respective wild-type littermates developed cardiac hypertrophy induced by angiotensin II (Ang II) or transverse aortic constriction (TAC). Cardiac-specific BACH1 knockout in mice protected the hearts against Ang II- and TAC-induced cardiac hypertrophy and fibrosis, and preserved cardiac function. Conversely, cardiac-specific BACH1 overexpression markedly exaggerated cardiac hypertrophy and fibrosis and reduced cardiac function in mice with Ang II- and TAC-induced hypertrophy. Mechanistically, BACH1 silencing attenuated Ang II- and norepinephrine-stimulated calcium/calmodulin-dependent protein kinase II (CaMKII) signalling, the expression of hypertrophic genes, and hypertrophic growth of cardiomyocytes. Ang II stimulation promoted the nuclear localization of BACH1, facilitated the recruitment of BACH1 to the Ang II type 1 receptor (AT1R) gene promoter, and then increased the expression of AT1R. Inhibition of BACH1 attenuated Ang II-stimulated AT1R expression, cytosolic Ca2+ levels, and CaMKII activation in cardiomyocytes, whereas overexpression of BACH1 led to the opposite effects. The increased expression of hypertrophic genes induced by BACH1 overexpression upon Ang II stimulation was suppressed by CaMKII inhibitor KN93. The AT1R antagonist, losartan, significantly attenuated BACH1-mediated CaMKII activation and cardiomyocyte hypertrophy under Ang II stimulation in vitro. Similarly, Ang II-induced myocardial pathological hypertrophy, cardiac fibrosis, and dysfunction in BACH1-Tg mice were blunted by treatment with losartan. CONCLUSION: This study elucidates a novel important role of BACH1 in pathological cardiac hypertrophy by regulating the AT1R expression and the Ca2+/CaMKII pathway, and highlights potential therapeutic target in pathological cardiac hypertrophy.

Transcriptomic and metabolic profiling of watermelon uncovers the role of salicylic acid and flavonoids in the resistance to cucumber green mottle mosaic virus.

Understanding the mechanisms underlying plant resistance to virus infections is crucial for viral disease management in agriculture. However, the defense mechanism of watermelon (Citrullus lanatus) against cucumber green mottle mosaic virus (CGMMV) infection remains largely unknown. In this study, we performed transcriptomic, metabolomic, and phytohormone analyses of a CGMMV susceptible watermelon cultivar 'Zhengkang No.2' ('ZK') and a CGMMV resistant wild watermelon accession PI 220778 (PI) to identify the key regulatory genes, metabolites, and phytohormones responsible for CGMMV resistance. We then tested several phytohormones and metabolites for their roles in watermelon CGMMV resistance via foliar application, followed by CGMMV inoculation. Several phenylpropanoid metabolism-associated genes and metabolites, especially those involved in the flavonoid biosynthesis pathway, were found to be significantly enriched in the CGMMV-infected PI plants compared with the CGMMV-infected 'ZK' plants. We also identified a gene encoding UDP-glycosyltransferase (UGT) that is involved in kaempferol-3-O-sophoroside biosynthesis and controls disease resistance, as well as plant height. Additionally, salicylic acid (SA) biogenesis increased in the CGMMV-infected 'ZK' plants, resulting in the activation of a downstream signaling cascade. SA levels in the tested watermelon plants correlated with that of total flavonoids, and SA pre-treatment up-regulated the expression of flavonoid biosynthesis genes, thus increasing the total flavonoid content. Furthermore, application of exogenous SA or flavonoids extracted from watermelon leaves suppressed CGMMV infection. In summary, our study demonstrates the role of SA-induced flavonoid biosynthesis in plant development and CGMMV resistance, which could be used to breed for CGMMV resistance in watermelon.

First report of tomato leaf curl New Delhi virus infecting several cucurbit plants in China.

In autumn 2022, a novel and devastating viral disease affecting cucurbits emerged in Ningbo (Zhejiang province), Haimen (Jiangsu province), and Shanghai, China, causing an approximate 650-hectare infestation and resulting in nearly US$15 million in economic losses. The incidence rates of infection reached up to 72.5% on muskmelon (Cucumis melo L. ssp melo), oriental melon (Cucumis melo L. var. agrestis), pumpkin (Cucurbita moschata), luffa (Luffa acutangula), and squash (Cucurbita pepo), and were highly associated with the presence of whitefly (Bemisia tabaci). Infected plants exhibited symptoms such as dwarf stunting, reduced leaf size, leaf chlorotic patches, malformation, fruit deformation, leaf downward rolling, and yellowing (Figure 1). To identify the pathogen, forty cucurbit leaf samples were collected from Haimen (18), Ningbo (19), and Shanghai (3) and tested for cucurbits chlorotic yellows virus (CCYV), cucurbit yellow stunting disorder virus (CYSDV), and Begomovirus using RT-PCR or PCR. All samples tested negative for CCYV and CYSDV using species-specific primers; however, 29 out of 40 samples tested positive (see Supplementary Table 1) for Begomovirus using the degenerate primer pairs PA/PB (Deng et al. 1994). PCR products from seven samples, representing different regions and hosts, underwent Sanger sequencing. The nucleotide sequences of these products showed 98.2-99% identity to tomato leaf curl New Delhi virus (ToLCNDV) by BLASTn. Subsequently, the 29 positive cucurbit samples were confirmed using ToLCNDV-specific primer pairs NDVAF/NDVAR and NDVBF/NDVBR (Jyothsna et al. 2013) for DNA-A and DNA-B, respectively. The DNA-A and DNA-B genome sequences of ToLCNDV isolates from Haimen (Haimen4), Ningbo (Ningbo6), and Shanghai (Shanghai1) were obtained using the primer pairs NDVAF/NDVAR, A1961F/A2645R (covering complete DNA-A sequences), NDVBF/NDVBR, and B1613F/B2579R (covering complete DNA-B sequences，see Supplementary Table 2). No amplicon was produced with primer pairs UNA101/UNA102 and beta01/beta02 (Supplementary Table 2) for detecting Alphasatellite and Betasatellite DNAs, respectively. The complete DNA-A genome sequences (2739 bp) of Haimen 4 (accession no. OP585369), Ningbo 6 (accession no. OP585370), and Shanghai 1 (accession no. OP683993) isolates exhibited 99.5-99.6% nucleotide identity to each other, and their highest nucleotide sequence identity (99.3-99.4%) was shared with the DNA-A of ToLCNDV-Zhejiang isolate (accession no. OP356207) from tomato in Zhejiang Province, China. The complete nucleotide sequences (2693 nt) of DNA-B for Haimen 4 (accession no. OP683995), Ningbo 6 (accession no. OP683996), and Shanghai 1 (accession no. OP683994) isolates showed 99.0-99.1% identity to each other, and their highest nucleotide sequence identity (~99.1%) was shared with the DNA-B of ToLCNDV-Zhejiang isolate (accession no. OP356208).All ToLCNDV isolates from mainland China, including the Zhejiang isolate and the three isolates in this study, shared 98.3-98.7% nucleotide sequence identity and 98.2-98.4% with the DNA-A genome of the severe isolate (accession no. HM159454) from tomato in New Delhi, India, and the DNA-B genome of the India:Delhi:Cucumis:2012 isolate from cucumber in New Delhi, India, respectively. However, the genome sequence identities between mainland and Taiwan isolates (accession nos. GU180095 and GU180096) were below 93%, suggesting that mainland China isolates of ToLCNDV are more closely related to the India isolate than to the Taiwan isolate.To fulfill Koch's postulates, infectious clones of the Haimen 4 isolate were constructed and agroinfiltrated into muskmelon, oriental melon, pumpkin, luffa, and squash plants. In brief, two plasmids, containing 1.56-mer DNA-A and 1.4-mer DNA-B genome sequences, were constructed using enzyme digestion and ligation, transformed into Agrobacterium tumefaciens strain GV3101, respectively, and then co-agroinfiltrated into cucurbit plants. Initial symptoms appeared in the new leaves at 7 days post-inoculation (DPI), followed by severe leaf curling, dwarfing, stunting, reduced leaf size, and chlorotic leaf patches at 18 DPI. The presence of DNA-A and DNA-B of ToLCNDV in inoculated plants was confirmed by PCR using primer pairs A1961F/A2645R and B1613F/B2579R, respectively. Collectively, the pathogen of this emerging disease has been identified as ToLCNDV. ToLCNDV was first reported on tomato in India and is now the most predominant and economically significant disease affecting cucurbit and solanaceous crops in Southeast and East Asia, the Middle East, and the Mediterranean Basin (Moriones et al. 2017). In China, ToLCNDV was initially reported on oriental melon in Taiwan (Chang et al. 2010) and subsequently on tomato (Lycopersicon esculentum) in Zhejiang province (Li et al. 2022). To the best of our knowledge, this is the first report of ToLCNDV infecting muskmelon, pumpkin, luffa, and squash in China. Further investigations on the epidemiology of this viral disease in China are needed.

Argonaute 1 and 5 proteins play crucial roles in the defence against cucumber green mottle mosaic virus in watermelon.

RNA silencing, a core part of plants' antiviral defence, requires the ARGONAUTE, DICER-like, and RNA-dependent RNA polymerase proteins. However, how these proteins contribute to watermelon's RNA interference (RNAi) pathway response to cucumber green mottle mosaic virus (CGMMV) has not been characterized. Here, we identify seven ClAGO, four ClDCL, and 11 ClRDR genes in watermelon and analyse their expression profiles when infected with CGMMV. ClAGO1 and ClAGO5 expression levels were highly induced by CGMMV infection. The results of ClAGO1 and ClAGO5 overexpression and silencing experiments suggest that these genes play central roles in watermelon's antiviral defence. Furthermore, co-immunoprecipitation and bimolecular fluorescence complementation experiments showed that ClAGO1 interacts with ClAGO5 in vivo, suggesting that ClAGO1 and ClAGO5 co-regulate watermelon defence against CGMMV infection. We also identified the ethylene response factor (ERF) binding site in the promoters of the ClAGO1 and ClAGO5 genes, and ethylene (ETH) treatment significantly increased ClAGO5 expression. Two ERF genes (Cla97C08G147180 and Cla97C06G122830) closely related to ClAGO5 expression were identified using co-expression analysis. Subcellular localization revealed that two ERFs and ClAGO5 predominantly localize at the nucleus, suggesting that enhancement of resistance to CGMMV by ETH is probably achieved through ClAGO5 but not ClAGO1. Our findings reveal aspects of the mechanisms underlying RNA silencing in watermelon against CGMMV.

Robust reconstruction of fluorescence molecular tomography based on adaptive adversarial learning strategy.

Objective.Fluorescence molecular tomography (FMT) is a promising molecular imaging modality for quantifying the three-dimensional (3D) distribution of tumor probes in small animals. However, traditional deep learning reconstruction methods that aim to minimize the mean squared error (MSE) and iterative regularization algorithms that rely on optimal parameters are typically influenced by strong noise, resulting in poor FMT reconstruction robustness.Approach.In this letter, we propose an adaptive adversarial learning strategy (3D-UR-WGAN) to achieve robust FMT reconstructions. Unlike the pixel-based MSE criterion in traditional CNNs or the regularization strategy in iterative solving schemes, the reconstruction strategy can greatly facilitate the performance of the network models through alternating loop training of the generator and the discriminator. Second, the reconstruction strategy combines the adversarial loss in GANs with the L1 loss to significantly enhance the robustness and preserve image details and textual information.Main results.Both numerical simulations and physical phantom experiments demonstrate that the 3D-UR-WGAN method can adaptively eliminate the effects of different noise levels on the reconstruction results, resulting in robust reconstructed images with reduced artifacts and enhanced image contrast. Compared with the state-of-the-art methods, the proposed method achieves better reconstruction performance in terms of target shape recovery and localization accuracy.Significance.This adaptive adversarial learning reconstruction strategy can provide a possible paradigm for robust reconstruction in complex environments, and also has great potential to provide an alternative solution for solving the problem of poor robustness encountered in other optical imaging modalities such as diffuse optical tomography, bioluminescence imaging, and Cherenkov luminescence imaging.

Ethylene enhances resistance to cucumber green mottle mosaic virus via the ClWRKY70-ClACO5 module in watermelon plants.

Introduction: Ethylene (ET) is involved in plant responses to viral infection. However, its molecular mechanisms and regulatory network remain largely unknown. Methods and results: In the present study, we report that cucumber green mottle mosaic virus (CGMMV) in watermelon (Citrullus lanatus) triggers ET production by inducing the expression of ClACO5, a key gene of the ET biosynthesis pathway through transcriptome data analysis and gene function validation. The knock-down of ClACO5 expression through virus-induced gene silencing in watermelon and overexpressing ClACO5 in transgenic Nicotiana benthamiana indicated that ClACO5 positively regulates CGMMV resistance and ET biosynthesis. The salicylic acid-responsive transcription factor gene ClWRKY70 shares a similar expression pattern with ClACO5. We demonstrate that ClWRKY70 directly binds to the W-box cis-element in the ClACO5 promoter and enhances its transcription. In addition, ClWRKY70 enhances plant responses to CGMMV infection by regulating ClACO5 expression in watermelon. Discussion: Our results demonstrate that the ClWRKY70-ClACO5 module positively regulates resistance to CGMMV infection in watermelon, shedding new light on the molecular basis of ET accumulation in watermelon in response to CGMMV infection.

First report of bacterial soft rot caused by Enterobacter mori affecting host watermelon.

In June 2021, bacterial stem rot-like symptoms were observed on the stems and leaves of watermelon (Citrullus lanatus cv. 'Zaojia') in Pingyu County, Zhumadian City, Henan Province, China (32.44N 114.24E), which showed brown to dark brown lesions on the stems (Fig. 1A). The stems then became scorched, and the leaves showed necrotic lesions with small water-soaked spots (Fig. 1B). Watermelon is a very important economic plant in this small county, where the watermelon planting area accounts for about 15% of the arable land area. Approximately 2 hectares of 'Zaojia' have been investigated, and the disease incidence rates were almost 20~30%, thus, causing severe economic losses. Ten symptomatic watermelon stems and leaves were randomly collected based on the typical symptoms, brought into the Lab and used to isolate the pathogen. Each infected tissue was excised and cut into small pieces (about 5 mm×5 mm) and surface disinfected with 1% NaClO for 3 min. The pieces were then rinsed three times in sterile distilled water (SDW) and dried by airing. These pieces (4-5 pieces per sample) were macerated in 200 µL SDW for 60 s in a sterile mortar and pestle. A volume of 5 µL suspensions of each sample were streaked onto two LB agar plates and incubated for 48 h at 28 °C in the dark. After incubation, the colonies on LB agar plate were small, round, raised, white to cream-colored, and had smooth margins (Fig. 2). Two strains from each plate were selected. The genomic DNA of all 40 strains was extracted using a Bacterial Genomic DNA Extraction Kit D1600 (Beijing Solarbio Science & Technology Co., Ltd., Beijing, China) according to the manufacturer's instructions. The 16S ribosomal RNA gene (27F:5'-AGA GTT TGA TCC TGG CTC AG-3', /1492R: 5'-CTA CGG CTA CCT TGT TAC GA-3'), and the three housekeeping genes, including gyrB (Trantas et al., 2013), icdA and proA (Ma et al., 2007), were amplified. Sequence analysis showed that 40 strains shared the same sequence, so only one sequence was submitted into GenBanK.The 16s rDNA partial sequences (SUB12134746) shared 100% similarity with E.mori (CP084692.1), and the gyrB (OP676246), icdA (OP676248) and proA (OP676247) genes shared 98.67%, 99.39% and 97.99% homology with those of E. mori (CP084692.1), respectively. Besides, the phylogenetic tree analysis based on multi-housekeeping gene joint gryB-icdA-proA showed that E.mori（OP676246-OP676248- OP676247）from watermelon was culsterd with the E.mori (CP084692.1) from South Korea and E.mori (CP055276.1) from kiwifruit (Fig. 3). Thus, E.mori was confirmed to be the pathogen responsible for bacterial soft rot of watermelon in this study. To confirm the pathogenicity, 15-day-old healthy cv. 'Zaojia' watermelon seedlings were inoculated by spraying all the seedlings with a bacterial suspension (1×10 8 CFU mL-1) at an incubation temperature of 28 °C and 70% relative humidity, and sterile distilled liquid LB medium was applied as a negative control treatment. Three times were conducted for the isolate, and each time included nine watermelon plants. After 10 days, only the inoculated cotyledons and leaves with the bacterial suspension showed bacterial leaf spots that resembled those observed on naturally infected watermelon cotyledons and leaves (Fig. 4A-C), whereas the control plants remained asymptomatic (Fig. 4D). Simultaneously, the watermelon stems were inoculated with the bacterium in vitro. Each stem was slightly wounded with a metal sponge and then sprayed with the bacterial suspension (108 CFU mL-1) of each isolate, and the experiment was repeated three times. Water-soaked symptoms were visible on the stems (Fig. 4E), while the control plants remained asymptomatic (Fig. 4F). The strains were then successfully re-isolated and identified by sequence analyses of their 16S ribosomal RNA gene and gyrB, icdA and proA genes. Therefore, the inoculation experiment of the isolatedbacterium fulfilled Koch's postulates. Previously, E. mori has been reported to cause bacterial wilt on white mulberry (Morus alba L.) (Zhu et al. 2022), peach fruit (Prunus persica) (Ahmad et al. 2021) and kiwifruit (Actinidia deliciosa [A. Chev.] CF Liang et AR Ferguson) (Zhang et al. 2021). To our knowledge, this is the first report of E. mori causing bacterial soft rot on watermelon in world.

AC5 protein encoded by squash leaf curl China virus is an RNA silencing suppressor and a virulence determinant.

Squash leaf curl China virus (SLCCNV) is a bipartite Begomovirus. The function of the protein AC5, which is encoded by SLCCNV, is unknown. Here, we confirmed that the 172-amino acids (aa) long AC5 protein of SLCCNV could suppress single-stranded RNA but not double-stranded RNA-induced post-transcriptional gene silencing (PTGS). Furthermore, we determined that the C-terminal domain (96-172 aa) of the AC5 protein was responsible for RNA silencing suppressor (RSS) activity via deletion mutant analysis. The AC5 protein can reverse GFP silencing and inhibit systemic silencing of GFP by interfering with the systemic spread of the GFP silencing signal. The SLCCNV AC5 protein was localized to both the nucleus and cytoplasm of Nicotiana benthamiana cells. Furthermore, deletion analysis showed that the putative nuclear localization signal (NLS, 102-155 aa) was crucial for the RNA silencing suppression activity of AC5. In addition, the AC5 protein elicited a hypersensitive response and enhanced potoao virus X (PVX) RNA accumulation in infected N. benthamiana plants. Using the infectious clones of the SLCCNV and SLCCNV-AC5 null mutants, mutational analysis confirmed that knockout of the AC5 gene abolished SLCCNV-induced leaf curl symptoms, showing SLCCNV AC5 is also a virulence determinant.

Colletotrichum Species Associated with Anthracnose Disease of Watermelon (Citrullus lanatus) in China.

Colletotrichum species are important plant pathogens, causing anthracnose in virtually every crop grown throughout the world. However, little is known about the species that infect watermelon. A total of 526 strains were isolated from diseased watermelon samples of eight major watermelon growing provinces in China. Phylogenetic analyses using seven loci (ITS, gadph, chs-1, his3, act, tub2, and gs) coupled with morphology of 146 representative isolates showed that they belonged to 12 known species of Colletotrichum, including C. aenigma, C. chlorophyti, C. fructicola, C. jiangxiense, C. karstii, C. magnum, C. nymphaeae, C. nigrum, C. orbiculare, C. plurivorum, C. sojae, and C. truncatum and three new species, here described as C. citrulli, C. kaifengense, and C. qilinense. Colletotrichum orbiculare was the dominant species. Pathogenicity tests revealed that all isolates of the species described above were pathogenic, with C. magnum and C. kaifengense being the most aggressive to leaves and fruits, respectively. This is the first report of C. aenigma, C. chlorophyti, C. fructicola, C. jiangxiense, C. nymphaeae, C. nigrum, C. plurivorum, and C. sojae on watermelon. These findings shed light on the Colletotrichum spp. involved in watermelon anthracnose and provide useful information for implementing effective control of watermelon anthracnose in China.

Clinical efficacy of early postoperative intensity-modulated radiotherapy combined with Temozolomide chemotherapy in the treatment of patients with malignant glioma.

Objectives: To evaluate the clinical efficacy of early postoperative intensity-modulated radiotherapy (IMRT) combined with temozolomide chemotherapy in the treatment of patients with malignant glioma. Methods: In this retrospective cohort study 80 patients with glioma surgery admitted to Chengde Central Hospital from January 2019 to January 2021 were selected and divided into two groups according to postoperative treatment: the experimental group and the control group, with 40 cases in each group. Patients in the experimental group received IMRT combined with temozolomide chemotherapy postoperatively, while those in the control group received IMRT alone. The clinical effects of patients were analyzed before treatment and three months after treatment, and the incidence of adverse reactions such as bone marrow suppression, gastrointestinal reactions, fever, and liver dysfunction were analyzed in the two groups within one month after treatment. Before treatment and two months after treatment, MMSE scale, QOL scale and KPS were used to compare the cognitive function and health status of the patients. All patients were followed up for one year after treatment, and the difference of disease progression-free survival and overall survival rate between the two groups was analyzed. Results: The effective rate of the experimental group was 70% after treatment, while that of the control group was 43.3%, with a statistically significant difference (P=0.04). The incidence of adverse reactions was 50% in the experimental group and 40% in the control group, with no statistically significant difference between the two groups (P=0.25). After treatment, MMSE score, QOL score and KPS score of the experimental group were significantly improved compared with those of the control group, with statistically significant differences between the two groups (MMSE score, QOL, P=0.00; KPS, P=0.01). Moreover, the two groups of patients were followed up for one year after treatment. The disease progression-free survival rate of the experimental group was 70% and that of the control group was 47.5%, with a statistically significant difference (P=0.04), and the overall survival rate of the experimental group was significantly higher than that of the control group after treatment, with a statistically significant difference (P=0.03). Conclusion: Early postoperative IMRT combined with temozolomide chemotherapy is an effective treatment regimen for patients with malignant glioma, boasting a variety of advantages such as high efficiency, cognitive function, favorable recovery of health status, significantly improved progression-free survival rate and overall survival rate, and no significant increase in adverse reactions.

Association between interleukin-19 gene polymorphisms and maternal puerperal infection.

Any bacterial infection of the genital tract after childbirth is called maternal puerperal infection. This infection accounts for 13% of pregnancy-related deaths and is the fifth leading cause of maternal mortality. Endometritis (postpartum uterine infection) has been associated with preeclampsia and maternal lethal bleeding in recent decades. In some studies, the presence of meconium in the amniotic fluid has been implicated in the development of endometritis. The study aimed to evaluate the association between interleukin-19 gene polymorphisms and maternal puerperal infection. In this study, 300 pregnant women with a gestational age of at least 37 weeks were studied. Patients were divided into two groups of 150 controls and cases. In the case group, amniotic fluid was impregnated with meconium, and in the control group, it was clear fluid. Both groups underwent cesarean section, and all received prophylactic antibiotics before surgery. Patients were evaluated for purpura infection in the first 40 days after delivery. Five ml of venous blood was taken from each patient and transferred to a tube containing EDTA anticoagulant. Genomic DNA was isolated using a particular kit. Then, the polymerase chain reaction was performed by the ARMS method. Data were analyzed using the chi-square test and SPSS software version 19 in case and control groups. This study's results indicate no significant difference in the frequency of AG, GG, and AA genotypes at position rs2243191 and rs1028181 IL-19 gene polymorphism between patients with puerperal infection and the control group (P>0.05). Also, no significant difference was observed in the frequency of both G and A alleles in the mentioned situations between patients and the control group (P>0.05). Based on the results of this study, no significant relationship was observed between IL-19 gene polymorphism at rs2243191 and rs1028181 locus and puerperal infection.

Construction of an Agrobacterium-mediated infectious cDNA clone of melon aphid-borne yellows virus.

Melon aphid-borne yellows virus (MABYV), a member of the genus Polerovirus in the family Solemoviridae, has widely spread in recent years and cause yellowing disease on cucurbits. Here, we obtained the complete genome sequence of MABYV bottle guard (Lagenaria siceraria) isolate MABYV-KF, and constructed its infectious cDNA clone under the control of the cauliflower mosaic virus (CaMV) 35S promoter by Gibson assembly. The 5,677 nt of its genome shared more than 94.00% sequence identity with the two known MABYV isolates. The inoculation results showed that MABYV infectious cDNA clone could systemically infect bottle guard, cucumber and muskmelon plants, and cause typical yellowing symptom. The virus progeny from the infectious clone could be transmitted between bottle guard plants by aphid. Further analyses revealed that point mutations in the F-box-like motif (Pro57) and C-terminal conserved sequence (Phe211) of P0 cause low viral accumulations in systematic leaves and failed to induce symptom. The infectious clone will be potentially a tool in the investigation of viral pathogenesis, virus-virus interaction and virus-host/-vector interactions.