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Heliconia subulata is a common ornamental plant, it has been widely planted in southern China for greening parks, roads, and residential areas. H. subulata plants with spots on their leaves were observed in East Coast Wetland Park (18°16'53.37â³N, 109°30'19.36â³E), Sanya City, Hainan Province, China on Aug. 31, 2023. The symptoms of the leaves are irregular gray-white, spots, that develop into brown and black, with yellow halos at the disease-health junction. Following an on-the-spot investigation, it was found that the incidence of the disease was 40 to 50%. The leaves were disinfected with 70% ethanol for 1 min, rinsed with sterile water 3 times, disinfected for 1 min with 0.1% HgCl2, rinsed with sterile water 3 times, dried, put on potato dextrose agar (PDA) and incubated at 28â for 7 days. The red conidia pile was selected from the culture, dispersed in sterile water and diluted to 20 µL containing 1 to 2 conidia. After absorbing 20 µL spore suspension for many times and inoculating it on the new PDA plate, five pure cultures of single spore, J-1-1 to J-1-5, were obtained. After 7 days of growth, the colonies were grayish aerial mycelium on the front and light orange conidia on the reverse. The white aerial mycelia, conidia, acervulus, and appressorium were observed (Supplementary Fig. S1). The morphological characteristics showed that the isolate had the same characteristics as the previously described Colletotrichum spp. (Wang et al. 2021). The genomic DNA of isolates J-1-1 and J-1-5 were extracted by Fungal DNA Kit (OMEGA bio-tek, Guangzhou, China). The internal transcribed spacer (ITS), glyceraldehyde-3-phosphate dehydrogenase (GADPH), and ß-tubulin 2 genes (TUB2) were amplified by primers ITS1/ITS4, GDF/GDR, and Bt2a/Bt2b, respectively (Weir et al. 2012). Based on sequencing and gene sequence alignment analysis, it was found that the consistency between the ITS sequences of isolates J-1-1 and J-1-5 was 99.82%. The consistency between GADPH and TUB2 sequences was 100%. The gene sequences of isolates J-1-1 and J-1-5 were submitted to GenBank with accession numbers PP455510/PP455511 (ITS), PP510210/PP510211 (GADPH) and PP510212/PP510213 (TUB2) respectively. Based on the BLAST analysis, the three sequences were more than 99% identical to those of the C. tropicale strain FC1 (ITS: MT192648, GAPDH: MT155819, TUB2: MT199874; Duan et al. 2022). A phylogenetic tree was constructed by MEGA 11 based on the ITS, GADPH, and TUB2 gene sequence by the maximum-likelihood method. The results showed that the isolates J-1-1 and J-1-5 were clustered with C. tropicale CBS:124949 (Supplementary Fig. S2). Based on morphological and molecular biological analysis, two isolates were identified as C. tropicale. To further test the pathogenicity of isolates J-1-1 and J-1-5, spore suspensions (1×106 conidia/mL) were prepared and 20 µL spore suspensions were inoculated on the leaves of healthy H. subulata potted plants stabbed with sterile toothpicks. Three leaves were inoculated in each treatment, and sterile water was inoculated as a control. The treated plants were placed in an incubator with a temperature of 28â, relative humidity of 90%, and light/dark (12h/12h). After 15 days, the spore suspension treatment showed the same symptoms as the naturally diseased H. subulata plants in the field, but the leaves treated with sterile water were not infected (Supplementary Fig. S1). The morphology of the isolates obtained from diseased leaves was the same as that of isolates J-1-1 and J-1-5 on the PDA plate. To our knowledge, this is the first report of H. subulata, a new host of C. tropicale causing anthracnose in China.
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Candida albicans (C. albicans), a microbe commonly isolated from Candida vaginitis patients with vaginal tract infections, transforms from yeast to hyphae and produces many toxins, adhesins, and invasins, as well as C. albicans biofilms resistant to antifungal antibiotic treatment. Effective agents against this pathogen are urgently needed. Antimicrobial peptides (AMPs) have been used to cure inflammation and infectious diseases. In this study, we isolated whole housefly larvae insect SVWC peptide 1 (WHIS1), a novel insect single von Willebrand factor C-domain protein (SVWC) peptide from whole housefly larvae. The expression pattern of WHIS1 showed a response to the stimulation of C. albicans. In contrast to other SVWC members, which function as antiviral peptides, interferon (IFN) analogs or pathogen recognition receptors (PRRs), which are the prokaryotically expressed MdWHIS1 protein, inhibit the growth of C. albicans. Eukaryotic heterologous expression of WHIS1 inhibited C. albicans invasion into A549 and HeLa cells. The heterologous expression of WHIS1 clearly inhibited hyphal formation both extracellularly and intracellularly. Furthermore, the mechanism of WHIS1 has demonstrated that it downregulates all key hyphal formation factors (ALS1, ALS3, ALS5, ECE1, HWP1, HGC1, EFG1, and ZAP1) both extracellularly and intracellularly. These data showed that heterologously expressed WHIS1 inhibits C. albicans invasion into epithelial cells by affecting hyphal formation and adhesion factor-related gene expression. These findings provide new potential drug candidates for treating C. albicans infection.
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Cowpea (Vigna unguiculata L.), a significant vegetable crop in China, holds particular prominence in the tropical island of Hainan. This region serves as the primary production area for the winter cultivation of cowpea. Phytoplasmas are an idiopathic parasitic pathogen and cannot be cultured in vitro. It is mainly transmitted by the insect vectors with the piercing and sucking mouthparts, such as leafhoppers, plant hoppers, and psyllids. (Kumari et al. 2019). On September 11, 2023, typical characteristics of phytoplasma diseases on cowpeas were observed in the experimental base of Hainan Academy of Agricultural Sciences (20°0'38.6964â³N, 110°21'35.4024â³E, Haikou City, Hainan Province, China), including reduced leaf size, chlorosis, and the development of broom-like branch deformities reminiscent, as depicted in Figure 1. At the same time, we found a large number of leafhoppers near the diseased plants, and we speculated that leafhoppers are the insect carriers that spread the disease. Following an on-site investigation, it was determined that the disease incidence ranges from 10% to 15%, leading to a consequential decrease of about 10% in yield, which is a potential disease that seriously threatens the cowpea industry in Hainan. Ten disease and healthy samples were meticulously collected and subsequently preserved at -80°C within the laboratory refrigerator. Three disease samples denoted as HNNKY-1, HNNKY-2, and HNNKY-3, were randomly chosen, and total DNA extraction was carried out employing the NuClean Plant Genomic DNA Kit (CWBIO, Taizhou, China), while three healthy samples were randomly selected as control. The 16S rRNA gene was amplified by PCR using the primer pairs P1/P7 (Schneider et al. 1995) and R16F2n / R16R2 (Lee et al. 1993) and the secA gene was amplified by PCR using the primer pairs secAfor1/secArev3 (Hodgetts et al. 2008). After agarose gel electrophoresis analysis, no DNA fragments were observed in the healthy leaf samples, whereas all three disease samples yielded amplification products. The PCR products were subsequently sequenced by Hainan Nanshan Biotech Co., Ltd., Haikou, China. After sequence analysis, it was found that the 16S rRNA gene and secA gene sequences HNNKY-1, HNNKY-2, and HNNKY-3 were identical to each other. We selected two gene sequences of strain HNNKY-3 to submission to the GenBank database, The length of the 16S rRNA gene sequence is 1193 base pairs, identified by the accession number OR666421, while the secA gene sequence is 825 base pairs in length, associated with the accession number OR661282. The phytoplasma strain HNNKY-3 was named 'Vigna unguiculata' witches'-broom phytoplasma. A BLAST analysis of the 16S rRNA gene revealed that strain HNNKY-3 displayed a 100% sequence match with 'Emilia sonchifolia' witches'-broom phytoplasma (MT420682), Peanut witches'-broom phytoplasma (OR239773), and 'Raphanus sativus' witches'-broom phytoplasma (OK491387). All of these phytoplasmas were classified within the 16SrII group. Based on the BLAST analysis of partial secA gene sequences, it was discerned that sequence homogeneity ranged from 99.27% to 99.74% among the studied sequences. These sequences were collectively classified as members of the 16SrII group. In addition, a phylogenetic tree was constructed by MEGA 11 (version 11.0.13) based on the 16Sr RNA gene and secA gene by the neighbor-joining method (Tamura et al. 2004). The results demonstrated the clustering of HNNKY-3 phytoplasma strains within the 16SrII group, as illustrated in Figures 2 and 3. A virtual RFLP analysis based on the 16S rRNA gene fragment of HNNKY-3 was conducted using the interactive online phytoplasma classification tool, iPhyClassifier (Zhao et al. 2009). The results indicated that the phytoplasma strain was the same as the reference pattern of the onion yellows phytoplasma of 16SrII-A (GenBank accession: L33765), and the similarity coefficient was 1.00. To best of our knowledge, this is the inaugural documentation of 16SrII Group-related phytoplasma infecting cowpea in Hainan, China, and lays the groundwork for further research on the dissemination of cowpea phytoplasma disease within China.
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BACKGROUND: Acute pancreatitis (AP) is a disease featuring acute inflammation of the pancreas and histological destruction of acinar cells. Approximately 20% of AP patients progress to moderately severe or severe pancreatitis, with a case fatality rate of up to 30%. However, a single indicator that can serve as the gold standard for prognostic prediction has not been discovered. Therefore, gaining deeper insights into the underlying mechanism of AP progression and the evolution of the disease and exploring effective biomarkers are important for early diagnosis, progression evaluation, and precise treatment of AP. AIM: To determine the regulatory mechanisms of tRNA-derived fragments (tRFs) in AP based on small RNA sequencing and experiments. METHODS: Small RNA sequencing and functional enrichment analyses were performed to identify key tRFs and the potential mechanisms in AP. Reverse transcription quantitative polymerase chain reaction (RT-qPCR) was conducted to determine tRF expression. AP cell and mouse models were created to investigate the role of tRF36 in AP progression. Lipase, amylase, and cytokine levels were assayed to examine AP progression. Ferritin expression, reactive oxygen species, malondialdehyde, and ferric ion levels were assayed to evaluate cellular ferroptosis. RNA pull down assays and methylated RNA immunoprecipitation were performed to explore the molecular mechanisms. RESULTS: RT-qPCR results showed that tRF36 was significantly upregulated in the serum of AP patients, compared to healthy controls. Functional enrichment analysis indicated that target genes of tRF36 were involved in ferroptosis-related pathways, including the Hippo signaling pathway and ion transport. Moreover, the occurrence of pancreatic cell ferroptosis was detected in AP cells and mouse models. The results of interference experiments and AP cell models suggested that tRF-36 could promote AP progression through the regulation of ferroptosis. Furthermore, ferroptosis gene microarray, database prediction, and immunoprecipitation suggested that tRF-36 accelerated the progression of AP by recruiting insulin-like growth factor 2 mRNA binding protein 3 (IGF2BP3) to the p53 mRNA m6A modification site by binding to IGF2BP3, which enhanced p53 mRNA stability and promoted the ferroptosis of pancreatic follicle cells. CONCLUSION: In conclusion, regulation of nuclear pre-mRNA domain-containing protein 1B promoted AP development by regulating the ferroptosis of pancreatic cells, thereby acting as a prospective therapeutic target for AP. In addition, this study provided a basis for understanding the regulatory mechanisms of tRFs in AP.
Assuntos
Pancreatite , Animais , Camundongos , Pancreatite/genética , Doença Aguda , Proteína Supressora de Tumor p53 , RNA de Transferência/genética , RNA , RNA Mensageiro/genéticaRESUMO
Hydrogenated titanium dioxide has attracted intensive research interests in pollutant removal applications due to its high photocatalytic activity. Herein, we demonstrate hydrogenated TiO2 nanofibers (H:TiO2 NFs) with a core-shell structure prepared by the hydrothermal synthesis and subsequent heat treatment in hydrogen flow. H:TiO2 NFs has excellent solar light absorption and photogenerated charge formation behavior as confirmed by optical absorbance, photo-Kelvin force probe microscopy and photoinduced charge carrier dynamics analyses. Photodegradation of various organic dyes such as methyl orange, rhodamine 6G and brilliant green is shown to take place with significantly higher rates on our novel catalyst than on pristine TiO2 nanofibers and commercial nanoparticle based photocatalytic materials, which is attributed to surface defects (oxygen vacancy and Ti3+ interstitial defect) on the hydrogen treated surface. We propose three properties/mechanisms responsible for the enhanced photocatalytic activity, which are: (1) improved absorbance allowing for increased exciton generation, (2) highly crystalline anatase TiO2 that promotes fast charge transport rate, and (3) decreased charge recombination caused by the nanoscopic Schottky junctions at the interface of pristine core and hydrogenated shell thus promoting long-life surface charges. The developed H:TiO2 NFs can be helpful for future high performance photocatalysts in environmental applications.