ABSTRACT
As a prevalent pathogenic fungus, Aspergillus westerdijkiae poses a threat to both food safety and human health. The fungal growth, conidia production and ochratoxin A (OTA) in A. weterdijkiae are regulated by many factors especially transcription factors. In this study, a transcription factor AwSclB in A. westerdijkiae was identified and its function in asexual sporulation and OTA biosynthesis was investigated. In addition, the effect of light control on AwSclB regulation was also tested. The deletion of AwSclB gene could reduce conidia production by down-regulation of conidia genes and increase OTA biosynthesis by up-regulation of cluster genes, regardless under light or dark conditions. It is worth to note that the inhibitory effect of light on OTA biosynthesis was reversed by the knockout of AwSclB gene. The yeast one-hybrid assay indicated that AwSclB could interact with the promoters of BrlA, ConJ and OtaR1 genes. This result suggests that AwSclB in A. westerdijkiae can directly regulate asexual conidia formation by activating the central developmental pathway BrlA-AbaA-WetA through up-regulating the expression of AwBrlA, and promote the light response of the strain by activating ConJ. However, AwSclB itself is unable to respond to light regulation. This finding will deepen our understanding of the molecular regulation of A. westerdijkiae development and secondary metabolism, and provide potential targets for the development of new fungicides.
Subject(s)
Aspergillus , Transcription Factors , Humans , Secondary Metabolism/genetics , Aspergillus/metabolism , Transcription Factors/genetics , Transcription Factors/metabolism , Fungal Proteins/genetics , Fungal Proteins/metabolism , Gene Expression Regulation, Fungal/geneticsABSTRACT
The Gleditsia sinensis Lam. widely grown in China is a perennial plant with medicinal properties (Zhang et al. 2016). Since 2019, the leaves of G. sinensis have exhibited yellowing and wilting, and the plants have gradually become stunted and dead in Taifeng park of Binhai New Area in Tianjin (39.02° N; 117.65° E). In this park, there are two types of G. sinensis, one is with round branch thorns, the other is with flat branch thorns. The G. sinensis with round branch thorns did not grow well and almost all plants had disease symptoms. The samples were collected on October, 2021 and deposited in Plant Disease Laboratory of Tianjin Agricultural University under accession no. PATAU211018. The disease symptoms consisted of foliage wilt (Figure 1A), plant drying and vascular tissue discoloration (Figure 1B). The stem sections from different plants were surface-disinfested in 0.6% NaClO, wiped with 75% ethanol and rinsed with sterile water. Thirty tissue samples were placed on Potato Dextrose Agar (PDA) medium and cultured at 28â for 7 days (Uppala et al. 2013). Thirty fungal isolates with the same morphological characteristics were obtained from the samples. Five representative isolates (PATAU211018-05, PATAU211018-07, PATAU211018-10, PATAU211018-12 and PATAU211018-21) were collected and purified using the single-spore method (Li et al. 2022). Colonies of the five isolates on PDA grew in a circular shape and showed abundant white densely fluffy aerial mycelium (Figure 1C). Morphological characteristics included septate and hyaline hyphae, long cylindrical monophialides (Figure 1D), macroconidia (Figure 1E) and microconidia (Figure 1F). Macroconidia were falcate, 2-5-septate, hyaline, 18-40 × 4-6 µm (n = 50). Microconidia were hyaline, oblong, 0-1-septate, 5-14 × 2-6 µm (n = 50). These morphological characteristics were consistent with the description of Fusarium solani. (Chitrampalam et al. 2018). PATAU211018-12 was randomly chosen for molecular analysis as the representative isolate given the similarity of these isolates. For further identification, the genomic DNA of isolate PATAU211018-12 was extracted. The fragments of internal transcribed spacer (ITS), translation elongation factor 1α (EF1α) gene and RNA polymerase II subunit (RPB2) were amplified and sequenced (O'Donnell et al. 2008; Carbone et al. 1999). The sequences of ITS, EF1α, and RPB2 of PATAU211018-12 were deposited in GenBank under the accession no. of OP735578, ON630412 and OP746032, respectively. Phylogenetic trees were constructed in MAGA X (Kumar et al. 2018) using the neighbor-joining (NJ) method based on the concatenated sequences of ITS, EF1α, and RPB2 (Figure 2). The isolate (PATAU211018-12) grouped with F. solani (JS-169) with a bootstrap value of 100 in the phylogenetic tree. The morphology and multi-gene phylogenetic analysis indicated that the new isolate is F. solani. Pathogenicity tests were carried out on one-year-old G. sinensis seedlings with round branch thorns (n=6). The F. solani isolate PATAU211018-12 was cultured in Potato Dextrose Broth (PDB) at 28°C on a shaker at 150 rpm for 5 days. Mycelia were filtered through four layers of sterilized lens paper and the conidia were obtained for pathogenicity tests. G. sinensis was infected by F. solani through root soaking method. The roots were inoculated by dipping in conidial suspension with the concentration of 107 conidia/mL for 30 minutes. Control plants (n=6) were treated with distilled water. Plants were in pots indoors at 25â. At 20 days after inoculation, the leaves of inoculated plants were chlorotic and wilted (Figure 1G), symptoms similar to those observed in the park. In contrast, the leaves of control plants were symptomless (Figure 1H). The pathogenicity assay was repeated three times. The fungal isolate was re-isolated from the disease tissues and verified as F. solani based on morphology and molecular character (ITS, EF1α and RPB2). F. solani has been reported as pathogens on many plants, such as Eriobotrya japonica (Wu et al. 2021), Fragaria × ananassa (Pastrana et al. 2014), Gastrodia elata (Li et al. 2022) and Hedysarum boreale (Uppala et al. 2013). To our knowledge, this is the first report of F. solani causing disease on G. sinensis in China. Identification of F. solani as a disease agent in G. sinensis will assist in disease management for this important tree crop.
ABSTRACT
This paper presents a metasurface-based linear-to-circular polarization converter with a flexible structure for conformal and wearable applications. The converter consists of nested S- and C-shaped split ring resonators in the unit cell and can convert linearly polarized incident waves into left-handed circularly polarized ones at 12.4 GHz. Simulation results show that the proposed design has a high polarization conversion rate and efficiency at the operating frequency. Conformal tests are also conducted to evaluate the performance under curvature circumstances. A minor shift in the operating frequency is observed when the converter is applied on a sinusoidal wavy surface.
ABSTRACT
BACKGROUND: Submucosal oesophageal squamous cell carcinoma is a quite infrequent and special type of oesophageal cancer. Its endoscopic manifestations are similar to those of submucosal oesophageal lesions, so it is easily ignored or misdiagnosed. Thus, the exact and timely diagnosis of oesophageal subepithelial lesions (SELs) is crucial. Endoscopic submucosal dissection (ESD) improves the diagnosis rate of malignant SELs without specific endoscopic presentations. CASE PRESENTATION: We report a 63-year-old patient with submucosal lesions of the oesophagus under endoscopy, but CT suggested mediastinal lymphadenectasis. Thus, there was a contradiction between them. After multidisciplinary consultation, endoscopic submucosal dissection (ESD) resection was finally recommended. The lesion was completely resected by endoscopic submucosal dissection. Postoperative pathology reported poorly differentiated squamous cell carcinoma, and subsequent PET-CT examination provided clarity, revealing mediastinal lymph node metastasis. CONCLUSIONS: Not all oesophageal SELs are benign, and a small number of SELs can be malignant. Submucosal oesophageal squamous cell carcinoma is a rare disease that may be characterized by oesophageal subepithelial lesions (SELs). Therefore, the precise and timely diagnosis of SELs is essential. If it is necessary to obtain lesion tissue for a definite diagnosis, ESD with less invasiveness is an excellent choice.
Subject(s)
Endoscopic Mucosal Resection , Esophageal Neoplasms , Esophageal Squamous Cell Carcinoma , Lymphatic Metastasis , Esophageal Neoplasms/diagnostic imaging , Esophageal Neoplasms/pathology , Esophageal Neoplasms/surgery , Esophageal Squamous Cell Carcinoma/surgery , Humans , Middle Aged , Positron Emission Tomography Computed TomographyABSTRACT
AIM: The role of triamcinolone acetonide (TA) in the prevention of esophageal stricture is not well established. This meta-analysis aimed to evaluate its safety and efficacy for the prevention of esophageal stricture after endoscopic submucosal dissection (ESD). METHODS: A comprehensive search was performed in electronic databases including PubMed, the Cochrane Library, Embase for possible controlled studies. The primary outcomes were stenosis rate and endoscopic balloon dilatation (EBD) sessions required, and secondary outcome included complications. Random effects were used to calculate the pooled outcome. Sensitivity analysis and publication bias were conducted to verify the robustness and reliability of the results. Results: Ten studies containing 499 patients were obtained. In the pooled analysis, statistical significance was found in triamcinolone acetonide injection reduced the incidence of stenosis (OR = 0.29, 95% CI [0.11, 0.80], P < 0.05) and the number of endoscopic balloon dilation (MD = -3.33, 95% CI [-4.15, -2.50], P < 0.0001) compared with control. Triamcinolone acetonide injection therapy did not increase the risk of complications (OR = -0.77%, CI [-1.62, 0.09], P = 0.08). Subgroup analysis indicated that the single injection of triamcinolone acetonide after endoscopic submucosal dissection significantly reduced the incidence of stenosis compared with without any prophylaxis. Different concentrations and single session volume of triamcinolone acetonide reduced the incidence of stenosis. It also showed that the dose according to the size of the lesion was more effective than the fixed dose in preventing esophageal stricture. Conclusion: Triamcinolone acetonide injection can reduce the incidence of stricture formation as well as the need for EBD sessions without increasing complications.
Subject(s)
Endoscopic Mucosal Resection , Esophageal Stenosis , Triamcinolone Acetonide , Humans , Endoscopic Mucosal Resection/adverse effects , Endoscopic Mucosal Resection/methods , Esophageal Stenosis/etiology , Esophageal Stenosis/prevention & control , Triamcinolone Acetonide/adverse effects , Treatment OutcomeABSTRACT
Enterobacter cloacae is a symbiotic bacterium, which is one of the species in intestinal microbiota in many humans and animals. In some cases, it causes harmful diseases in humans. More and more studies showed that E. cloacae caused disease on plants, such as macadamia, ginger, mulberry, onion, chili pepper and rice. Garlic (Allium sativum L.) is one of crops with economic importance in the world. It is also widely grown in China. During 2018 to 2020, the naturally infected garlic bulbs from garlic fields in Kaifeng of Henan Province (34.55° N; 114.78° E) showed dry brown discoloration and rot symptoms. The diseased garlic seriously affected its edible value. Voucher specimens collected on June, 2019 were deposited in Plant Disease Laboratory of Tianjin Agricultural University under accession no. PATAU190620. To identify the causal agent of this disease, the bulb tissues of infected garlic were surface-disinfested in 0.6% sodium hypochlorite, dipped in75% ethanol, and then dipped in sterile distilled water. These bulbs were plated on LB medium and incubated at 37â. A number of white colonies grew on the medium after plating for 16 h. All colonies were round, white, opaque, smooth, and gram-negative, which is a typical characteristic of Enterobacter. To confirm the initial identification of the isolated bacterium, the fragments of 16S rRNA gene and gyrA gene of 6 colonies were amplified, respectively. The PCR products were purified and sequenced. All 16S rRNA and gyrA sequences were identical to each other. The sequences of 16S rRNA gene and gyrA gene were deposited in GenBank with accession numbers MW730711 and MW768876, respectively. BLAST searches were conducted using the sequences of 16S rRNA and gyrA. The results showed 99.72%, and 96.91% identity with the corresponding sequences of E. cloacae strain CBG15936 (CP046116.1), respectively. Phylogenetic trees were performed using the neighbor-joining (NJ) method of MAGA X based on the sequences of 16S rRNA gene and gyrA gene. Phylogenetic tree indicated that isolates are most likely E. cloacae. Pathogenicity tests were performed by puncturing garlic bulbs with a hypodermic needle, followed by dipping in bacterial suspension with the concentration of 2×108 CFU for 5 minutes. As control, the garlic bulbs were treated with sterile water. The inoculated and control were incubated at 30°C. 7 days after inoculation, brown discoloration and rot were developed on all inoculated garlic bulbs. No symptoms were observed in the control group.The symptoms were similar to that observed on the original diseased garlic bulbs. The garlic bulbs in inoculated and control were ten replicates in each independent biological experiments. The pathogenicity tests were conducted three times with similar results. The bacteria were re-isolated from the symptomatic diseased garlics and confirmed as E. cloacae by morphological and sequence analyses as above. The re-isolated bacteria were identified by biochemical and physiological characteristics using API 20E strips. The results of the identification were identical to those of the edible ginger strains and the chili pepper strains. As far as we know, this is the first report of bulb decay on garlic caused by E. cloacae. The results are of great significance not only for the management of garlic bulbs during postharvest handling and storage, but also for the further research of opportunistic human pathogens E. cloacae.
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Purpureocillium lilacinum of Ophiocordycipitaceae is one of the most promising and commercialized agents for controlling plant parasitic nematodes, as well as other insects and plant pathogens. However, how the fungus functions at the molecular level remains unknown. Here, we sequenced two isolates (PLBJ-1 and PLFJ-1) of P. lilacinum from different places Beijing and Fujian. Genomic analysis showed high synteny of the two isolates, and the phylogenetic analysis indicated they were most related to the insect pathogen Tolypocladium inflatum. A comparison with other species revealed that this fungus was enriched in carbohydrate-active enzymes (CAZymes), proteases and pathogenesis related genes. Whole genome search revealed a rich repertoire of secondary metabolites (SMs) encoding genes. The non-ribosomal peptide synthetase LcsA, which is comprised of ten C-A-PCP modules, was identified as the core biosynthetic gene of lipopeptide leucinostatins, which was specific to P. lilacinum and T. ophioglossoides, as confirmed by phylogenetic analysis. Furthermore, gene expression level was analyzed when PLBJ-1 was grown in leucinostatin-inducing and non-inducing medium, and 20 genes involved in the biosynthesis of leucionostatins were identified. Disruption mutants allowed us to propose a putative biosynthetic pathway of leucinostatin A. Moreover, overexpression of the transcription factor lcsF increased the production (1.5-fold) of leucinostatins A and B compared to wild type. Bioassays explored a new bioactivity of leucinostatins and P. lilacinum: inhibiting the growth of Phytophthora infestans and P. capsici. These results contribute to our understanding of the biosynthetic mechanism of leucinostatins and may allow us to utilize P. lilacinum better as bio-control agent.
Subject(s)
Paecilomyces/genetics , Paecilomyces/metabolism , Peptides/metabolism , Phytophthora/microbiology , Antimicrobial Cationic Peptides , Chromatography, High Pressure Liquid , Gene Expression Profiling , Genes, Fungal , Genomics , Oligonucleotide Array Sequence Analysis , Pest Control, Biological/methods , Phylogeny , Polymerase Chain Reaction , TranscriptomeABSTRACT
Depressive symptoms are common in Parkinson's disease (PD), but the pathophysiology and neural basis underlying depression in PD is not well understood. Abnormal functional connectivity of the amygdala with various cortical and subcortical areas has been observed in major depressive disorder, indicating that dysfunction of the corticolimbic network may be involved in the pathogenesis of major depressive disorder. However, little is known about alterations of amygdala functional connectivity in depressed PD patients. In the present study, 20 depressed PD patients, 40 nondepressed PD patients, and 43 matched healthy controls underwent neuropsychological tests and resting-state functional MRI scanning. Between-group differences in amygdala functional connectivity network were examined using t tests. Compared to the nondepressed PD patients, depressed PD patients showed increased left amygdala functional connectivity with the bilateral mediodorsal thalamus, right amygdala functional connectivity with the left superior temporal gyrus, and left calcarine gyrus. Compared to the healthy controls, the depressed PD group also showed increased left amygdala functional connectivity with the bilateral mediodorsal thalamus, but decreased left amygdala functional connectivity with the left putamen, left inferior frontal gyrus, and the right cerebellum, as well as decreased right amygdala functional connectivity with the left inferior orbitofrontal gyrus, the left gyrus rectus, and the right putamen. The increased connectivity between limbic regions and decreased connectivity between the corticolimbic networks may reflect impaired high-order cortical regulatory effects on the emotion-related limbic areas, which may lead to mood dysregulation. Our study should advance the understanding of neural mechanisms underlying depression in PD.
Subject(s)
Amygdala/physiopathology , Brain Mapping , Depression/physiopathology , Depressive Disorder/physiopathology , Emotions/physiology , Parkinson Disease/physiopathology , Adult , Aged , Amygdala/pathology , Depression/diagnosis , Depression/etiology , Depressive Disorder/diagnosis , Depressive Disorder/etiology , Female , Humans , Image Processing, Computer-Assisted/methods , Magnetic Resonance Imaging/methods , Male , Middle Aged , Neural Pathways/pathology , Neuropsychological Tests , Parkinson Disease/complications , Parkinson Disease/diagnosisABSTRACT
INTRODUCTION: Ochratoxins (OTs) are worldwide regulated mycotoxins contaminating a variety of food-environment and agro-environment. Several Aspergillus and Pencillium species synthesize OTs from a six-gene biosynthetic gene cluster (BGC) to produce the highly toxic final product OTA. Although many studies on OTA-degrading enzymes were performed, high efficiency enzymes with strong stability are extremely needed, and the OTA degrading mechanism is poorly understood. OBJECTIVES: The study aimed to explore the OT-degradation enzyme and investigate its degradation mechanisms in Metarhizium, which contain an OT biosynthetic gene cluster. METHODS: Phylogenomic relationship combined with RNA expression analysis were used to explore the distribution of OT BGC in fungi. Bioactivity-guided isolation and protein mass spectrometry were conducted to trace the degrading enzymes in Metarhizium spp., and the enzymes were heterologously expressed in E. coli and verified by in vitro assays. Structure prediction and point mutation were performed to reveal the catalytic mechanism of MbAmh1. RESULTS: Beyond Aspergillus and Pencillium species, three species of the distant phylogenetic taxon Metarhizium contain an expressed OT-like BGC but lack an otaD gene. Unexpectedly, no OT BGC products were found in some Metarhizium species. Instead, Metarhizium metabolized both OTA and OTB to their non-toxic degradation products. This activity of M. brunneum was attributed to an intracellular hydrolase MbAmh1, which was tracked by bioactivity-guided proteomic analysis combined with in vitro reaction. Recombinant MbAmh1 (5 µg/mL) completely degraded 1 µg/mL OTA within 3 min, demonstrating a strong degrading ability towards OTA. Additionally, MbAmh1 showed considerable temperature adaptability ranging from 30 to 70 °C and acidic pH stability ranging from 4.0 to 7.0. Identification of active sites supported the crucial role of metal iron for this enzymatic reaction. CONCLUSION: These findings reveal different patterns of OT synthesis in fungi and provide a potential OTA degrading enzyme for industrial applications.
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Background: GJB2 plays an essential role in the growth and progression of several cancers. However, asystematic pan-cancer analysis of GJB2 is lacking. Therefore, in this study, we performed a comprehensive pan-cancer analysis to determine the potential role of GJB2 in prognostic prediction and cancer immunotherapy response. Methods: The differential expression of GJB2 in the tumor and adjacent normal tissues of various cancer types was analyzed using the TIMER, GEPIA, and Sangerbox databases. GEPIA and Kaplan-Meier plotter databases were used to analyze the survival outcomes based on GJB2 expression levels in pan-cancer. Furthermore, the association of GJB2 expression with the immune checkpoint (ICP) genes, tumor mutational load (TMB), microsatellite instability (MSI), neoantigens, and tumor infiltration of immune cells was analyzed using via the Sangerbox database. The cBioPortal database was used to determine the characteristics of GJB2 gene alterations in the cancer tissues. The STRING database was used to identify the GJB2-binding proteins. GEPIA database was used to identify the GJB2 co-expressed genes. DAVID was used to perform the functional enrichment analysis of gene ontology (GO) terms and KEGG pathways associated with GJB2. Finally, the mechanistic role of GJB2 in pancreatic adenocarcinoma (PAAD) was analyzed using the LinkedOmics database. Results: The GJB2 gene was highly expressed in a variety of tumors. Furthermore, GJB2 expression levels showed significant positive or negative association with the survival outcomes in various cancers. GJB2 expression levels cor related with tumor mutational burden, microsatellite instability, neoantigens, and tumor infiltration of immune cells in multiple cancers. This suggested that GJB2 played a critical role in the tumor microenvironment. Functional enrichment analysis showed that the biological role of GJB2 in tumors included modulation of gap junction-mediated intercellular transport, regulation of cell communication by electrical coupling, ion transmembrane transport, autocrine signaling, apoptotic signaling pathway, NOD-like receptor signaling pathway, p53 signaling pathway, and PI3K-Akt signaling pathway. Conclusions: Our study demonstrated that GJB2 played a significant role in tumorigenesis and tumor immunity in multiple cancers. Furthermore, GJB2 is a potential prognostic biomarker and a promising therapeutic target in multiple types of cancers.
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Ochratoxin A (OTA) contamination and the associated issues of food security, food safety and economic loss are widespread throughout the world. The occurrence of OTA depends on ochratoxigenic fungi, foodstuffs and their environment. In this review, natural occurrence and control strategy of OTA, with a focus on the impact of environmental factors, are summarized. First, this manuscript introduces potentially contaminated foodstuffs, including the emerging ones which are not regulated in international legislation. Secondly, it gives an update of native producers based on foodstuffs and OTA biosynthesis. Thirdly, complicated environmental regulation is disassembled into individual factors in order to clarify their regulatory effect and mechanism. Finally, to emphasize control OTA at all stages of foodstuffs from farm to table, strategies used at crop planting, harvest, storage and processing stages are discussed.
Subject(s)
Aspergillus , Ochratoxins , Food Contamination/analysis , Ochratoxins/analysis , Food SafetyABSTRACT
Aspergillus westerdijkiae, the producer of ochratoxin A (OTA), which is of worldwide concern, is an import fungal species in agriculture, food, and industry. Here, we got the uridine auxotrophic mutant of A. westerdijkiae by deleting AwpyrG. The ΔAwpyrG could be used for bio-transformation with exogenous AfpyrG expression cassette as a selection marker. In order to enhance the efficiency of gene targeting, Awku70 and Awlig4 were homologously deleted from ΔAwpyrG. The efficiencies of homologous replacement for ΔAwku70 and ΔAwlig4 were 95.7 and 87.0% in the deletion of AwAreA, respectively, demonstrating a drastic increase from 4.3% of the wild type (WT) strain. Furthermore, the function of AwAreA was identified with AwAreA deletion mutant and the control strain ΔAwku70. AwAreA regulated the growth and conidiation of A. westerdijkiae in response to nitrogen sources. The concentration of OTA for ΔAwku70 was in the range of 19.4 to 186.9 ng/cm2 on all kinds of nitrogen sources. The OTA production influenced by the deletion of AwAreA was different based on nitrogen sources. Pathogenicity assays on pears, grapes, salted meat, and cheese showed that AwAreA acted as a negative regulator in the infection of food substrates. Therefore, the genetic methods and engineered strains enable us to substantially expand the use of A. westerdijkiae, one of more than twenty OTA-producing fungi, in the study of mycotoxin biosynthesis and regulation, and consequently to aim at providing new ways for controlling this pathogen.
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Aspergillus ochraceus, generally known as a food spoilage fungus, is the representative species in Aspergillus section Circumdati. A. ochraceus strains are widely distributed in nature, and usually isolated from cereal, coffee, fruit, and beverage. Increasing cases suggest A. ochraceus acts as human and animal pathogens due to producing the mycotoxins. However, in terms of benefits to mankind, A. ochraceus is the potential source of industrial enzymes, and has excellent capability to produce diverse structural products, including polyketides, nonribosomal peptides, diketopiperazine alkaloids, benzodiazepine alkaloids, pyrazines, bis-indolyl benzenoids, nitrobenzoyl sesquiterpenoids, and steroids. This review outlines recent discovery, chemical structure, biosynthetic pathway, and bio-activity of the natural compounds from A. ochraceus.
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Aspergillus ochraceus is reported to be the major contributor of ochratoxin A (OTA), classified as one of the possible human carcinogen (group 2B) by the International Agency for Research on Cancer. The heterotrimeric velvet complex proteins, LaeA/VeA/VelB, have been most studied in fungi to clarify the relation between light-dependent morphology and secondary metabolism. To explore possible genetic targets to control OTA contamination, we have identified laeA, veA, and velB in A. ochraceus. The loss of laeA, veA, and velB yielded mutants with differences in vegetative growth and conidial production. Especially, ΔlaeA almost lost the ability to generate conidiaphore under dark condition. The deletion of laeA, veA, and velB drastically reduced the production of OTA. The wild-type A. ochraceus produced about 1 and 7 µg/cm2 OTA under light and dark conditions on media, whereas the three gene deletion mutants produced less than 20 ng/cm2 OTA, which was correlated with a down regulation of OTA biosynthetic genes. Pathogenicity studies of ΔlaeA, ΔveA, and ΔvelB showed their reduction in disease severity in pears. Furthermore, 66.1% of the backbone genes in secondary metabolite gene cluster were significantly regulated, among which 81.6% were downregulated. Taking together, these results revealed that velvet complex proteins played crucial roles in asexual development, secondary metabolism, and fungal virulence in A. ochraceus.
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Fusarium oxysporum is a soil-born fungus that induces wilt and root rot on a variety of plants. F. oxysporum f. sp. conglutinans (Foc) can cause wilt disease on cabbage. This study showed that a homolog of SIX1 protein in the Arabidopsis infecting isolate Fo5176 (Fo5176-SIX1) had four isoforms in the conidia of Foc by proteomic analysis. Thus, we analyzed the roles of protein Foc-SIX1. Gene expression analysis showed that, compared to the expression in mycelia, dramatically altered expression of Foc-SIX1 could be detected after infecting cabbages, and Foc-SIX1 was highly expressed in conidia under axenic culture condition. Furthermore, we knocked out the Foc-SIX1 gene and found that Foc-ΔSIX1 mutants had significantly reduced virulence compared with wild type isolate, and full virulence was restored by complementation of Foc-ΔSIX1 mutants with Foc-SIX1. Thus, we concluded that SIX1 in Foc was required for full virulence on cabbage. We also complemented Foc-ΔSIX1 with SIX1 gene in F. oxysporum f. sp. lycopersici (Fol) and found Foc-ΔSIX1::Fol-SIX1 mutants did not affect the virulence of Foc-ΔSIX1. The results confirmed that Fol-SIX1 was not capable of replacing the role of Foc-SIX1 in Foc on the disease symptom development of cabbage. The roles of Fol-SIX1 on virulence might rely on host specificity.
Subject(s)
Brassica/microbiology , Fungal Proteins/genetics , Fusarium/pathogenicity , Virulence/genetics , Fusarium/genetics , Gene Deletion , Genes, Fungal , PhylogenyABSTRACT
The alterations of interhemispheric resting-state functional connectivity (FC) in Parkinson's disease (PD) with depression remain unclear, so we aimed to explore the differences of interhemispheric FC between PD with and without depression. Twenty-one depressed PD (DPD) patients, 49 non-depressed PD (NDPD) patients and 50 matched healthy controls (HC) participated in this study. Resting-state functional magnetic resonance imaging (fMRI) data were analyzed with the voxel-mirrored homotopic connectivity (VMHC) approach. The DPD patients showed lower VMHC values in the bilateral dorsolateral prefrontal cortex (DLPFC) and calcarine cortex compared to both NDPD and HC groups, and further receiver operating characteristic curves (ROC) analyses revealed that the VMHC in these two brain areas could be used as biomarkers to distinguish DPD from NDPD and from HC. The pooled PD patients (both DPD and NDPD) exhibited decreased VMHC in the bilateral putamen, middle occipital gyrus (MOG), postcentral gyrus (PoCG), paracentral lobule (PCL) and cerebellum posterior lobe when compared with HC. Decreased VMHC values within the DLPFC and calcarine cortex appeared to be unique features for DPD and might be used as potential neuroimaging markers to distinguish DPD patients from NDPD and HC groups. These findings may underlie the neural mechanisms of depression in PD.
Subject(s)
Depression/physiopathology , Parkinson Disease/physiopathology , Aged , Brain/diagnostic imaging , Case-Control Studies , Depression/complications , Depression/diagnostic imaging , Female , Humans , Male , Middle Aged , Parkinson Disease/complications , Parkinson Disease/diagnostic imagingABSTRACT
Pancreatic ductal adenocarcinoma (PDAC) is a commonly fatal tumour. It is characterized by early metastasis and high mortality. Many patients die as a result of PDAC tumour progression. However, the underlying mechanism of invasion and metastasis in PDAC is still not fully understood. Previous studies showed that the Notch signalling pathway may play an important role in the progression of tumour invasion and metastasis. However, it is not yet known whether the Notch signalling pathway participates in the progression of invasion in PDAC. In the present study, immunohistochemistry showed that a high expression of Notch3 was correlated with tumour grade, metastasis, venous invasion and American Joint Committee on Cancer (AJCC) tumor-node-metastasis (TNM) stage. Kaplan-Meier curves suggested that a high expression of Notch3 was a significant risk factor for shortened survival time. We also showed that inhibition of Notch3 had an antiinvasion role in PDAC cells. In vitro, the inhibition of Notch3 reduced the migration and invasion capabilities of PDAC cells by regulating the expressions of E-cadherin, CD44v6, MMP-2, MMP-9, VEGF and uPA via regulating the COX-2 and ERK1/2 pathways. These results indicated that downregulation of the Notch signalling pathway may be a novel and useful approach for preventing and treating PDAC invasion.
Subject(s)
Adenocarcinoma/genetics , Biomarkers, Tumor/biosynthesis , Carcinoma, Pancreatic Ductal/genetics , Neoplasm Proteins/biosynthesis , Receptor, Notch3/biosynthesis , Adenocarcinoma/pathology , Adult , Aged , Aged, 80 and over , Biomarkers, Tumor/genetics , Carcinoma, Pancreatic Ductal/pathology , Cell Line, Tumor , Female , Gene Expression Regulation, Neoplastic , Humans , Kaplan-Meier Estimate , Lymphatic Metastasis , Male , Middle Aged , Neoplasm Invasiveness/genetics , Receptor, Notch3/genetics , Risk FactorsABSTRACT
Depressive symptoms are common in Parkinson's disease (PD), but the neurophysiological mechanisms of depression in PD are poorly understood. The current study attempted to examine disrupted spontaneous local brain activities and functional connectivities that underlie the depression in PD. We recruited a total of 20 depressed PD patients (DPD), 40 non-depressed PD patients (NDPD) and 43 matched healthy controls (HC). All the subjects underwent neuropsychological tests and resting-state fMRI scanning. The between-group differences in the amplitude of low frequency fluctuations (ALFF) of BOLD signals were examined using post-hoc tests after the analysis of covariance. Compared with the NDPD and HC, the DPD group showed significantly increased ALFF in the left median cingulated cortex (MCC). The functional connectivity (FC) between left MCC and all the other voxels in the brain were then calculated. Compared with the HC and NDPD group, the DPD patients showed stronger FC between the left MCC and some of the major nodes of the default mode network (DMN), including the post cingulated cortex/precuneus, medial prefrontal cortex, inferior frontal gyrus, and cerebellum. Correlation analysis revealed that both the ALFF values in the left MCC and the FC between the left MCC and the nodes of DMN were significantly correlated with the Hamilton Depression Rating Scale score. Moreover, higher local activities in the left MCC were associated with increased functional connections between the MCC and the nodes of DMN in PD. These abnormal activities and connectivities of the limbic-cortical circuit may indicate impaired high-order cortical control or uncontrol of negative mood in DPD, which suggested a possible neural mechanism of the depression in PD.
Subject(s)
Brain Mapping , Cerebral Cortex/physiopathology , Connectome , Depression/physiopathology , Limbic System/physiopathology , Nerve Net/physiopathology , Parkinson Disease/psychology , Affect/physiology , Aged , Cerebellum/pathology , Cerebellum/physiopathology , Cerebral Cortex/pathology , Depression/pathology , Female , Humans , Limbic System/pathology , Magnetic Resonance Imaging , Male , Middle Aged , Nerve Net/pathology , Neuropsychological Tests , Organ Specificity , Parkinson Disease/pathology , Parkinson Disease/physiopathology , RestABSTRACT
Fusarium oxysporum is a soil-inhabiting fungus that induces vascular wilt and root rot in a variety of plants. F. oxysporum f. sp. conglutinans (Foc), which comprises two races, can cause wilt disease in cabbage. Compared with race 1 (52557(-TM), R1), race 2 (58385(-TM), R2) exhibits much stronger pathogenicity. Here, we provide the first proteome reference maps for Foc mycelium and conidia and identify 145 proteins with different abundances among the two races. Of these proteins, most of the high-abundance proteins in the R2 mycelium and conidia are involved in carbohydrate, amino acid and ion metabolism, which indicates that these proteins may play important roles in isolate R2's stronger pathogenicity. The expression levels of 20 typical genes demonstrate similarly altered patterns compared to the proteomic analysis. The protein glucanosyltransferase, which is involved in carbohydrate metabolism, was selected for research. We knocked out the corresponding gene (gas1) and found that Foc-∆gas1 significantly reduced growth rate and virulence compared with wild type isolates. These results deepened our understanding of the proteins related to F. oxysporum pathogenicity in cabbage Fusarium wilt and provided new opportunities to control this disease.