A pathogenesis-related protein 1 of Cucurbita moschata responds to powdery mildew infection.

Pumpkin (Cucurbita moschata Duch.) productivity is severely hindered by powdery mildew (PM) worldwide. The causative agent of pumpkin PM is Podosphaera xanthii, a biotrophic fungus. Pathogenesis-related protein 1 (PR1) homolog was previously identified from transcriptomic analysis of a PM-resistant pumpkin. Here, we investigated the effects of CmPR1 gene from pumpkin for resistance to PM. Subcellular localization assay revealed that CmPR1 is a cytoplasmic protein in plants. The expression of CmPR1 gene was strongly induced by P. xanthii inoculation at 48 h and exogenous ethylene (ET), jasmonic acid (JA) and NaCl treatments, but repressed by H2O2 and salicylic acid (SA) treatments. Visual disease symptoms, histological observations of fungal growth and host cell death, and accumulation of H2O2 in transgenic tobacco plants indicated that CmPR1 overexpression significantly enhanced the resistance to Golovinomyces cichoracearum compared to wild type plants during PM pathogens infection, possibly due to inducing cell death and H2O2 accumulation near infected sites. The expression of PR1a was significantly induced in transgenic tobacco plants in response to G. cichoracearum, suggesting that CmPR1 overexpression positively modulates the resistance to PM via the SA signaling pathway. These findings indicate that CmPR1 is a defense response gene in C. moschata and can be exploited to develop disease-resistant crop varieties.

Corrigendum: Expression of Pumpkin CmbHLH87 Gene Improves Powdery Mildew Resistance in Tobacco.

[This corrects the article DOI: 10.3389/fpls.2020.00163.].

CaSBP11 Participates in the Defense Response of Pepper to Phytophthora capsici through Regulating the Expression of Defense-Related Genes.

Squamosa promoter binding protein (SBP)-box genes are plant-specific transcription factors involved in plant growth and development, morphogenesis and biotic and abiotic stress responses. However, these genes have been understudied in pepper, especially with respect to defense responses to Phytophthora capsici infection. CaSBP11 is a SBP-box family gene in pepper that was identified in our previous research. Silencing CaSBP11 enhanced the defense response of pepper plants to Phytophthora capsici. Without treatment, the expression of defense-related genes (CaBPR1, CaPO1, CaSAR8.2 and CaDEF1) increased in CaSBP11-silenced plants. However, the expression levels of these genes were inhibited under transient CaSBP11 expression. CaSBP11 overexpression in transgenic Nicotiana benthamiana decreased defense responses, while in Arabidopsis, it induced or inhibited the expression of genes in the salicylic acid and jasmonic acid signaling pathways. CaSBP11 overexpression in sid2-2 mutants induced AtNPR1, AtNPR3, AtNPR4, AtPAD4, AtEDS1, AtEDS5, AtMPK4 and AtNDR1 expression, while AtSARD1 and AtTGA6 expression was inhibited. CaSBP11 overexpression in coi1-21 and coi1-22 mutants, respectively, inhibited AtPDF1.2 expression and induced AtPR1 expression. These results indicate CaSBP11 has a negative regulatory effect on defense responses to Phytophthora capsici. Moreover, it may participate in the defense response of pepper to Phytophthora capsici by regulating defense-related genes and the salicylic and jasmonic acid-mediated disease resistance signaling pathways.

Expression of Pumpkin CmbHLH87 Gene Improves Powdery Mildew Resistance in Tobacco.

Powdery mildew (PM), caused by Podosphaera xanthii, is a major threat to the global cucurbit yield. The molecular mechanisms underlying the PM resistance of pumpkin (Cucurbita moschata Duch.) are largely unknown. A homolog of the basic helix-loop-helix (bHLH) transcription factor was previously identified through a transcriptomic analysis of a PM-resistant pumpkin. In this study, this bHLH homolog in pumpkin has been functionally characterized. CmbHLH87 is present in the nucleus. CmbHLH87 expression in the PM-resistant material was considerably downregulated by PM; and abscisic acid, methyl jasmonate, ethephon, and NaCl treatments induced CmbHLH87 expression. Ectopic expression of CmbHLH87 in tobacco plants alleviated the PM symptoms on the leaves, accelerated cell necrosis, and enhanced H2O2 accumulation. The expression levels of PR1a, PR5, and NPR1 were higher in the PM-infected transgenic plants than in PM-infected wild-type plants. Additionally, the chlorosis and yellowing of plant materials were less extensive and the concentration of bacteria at infection sites was lower in the transgenic tobacco plants than in the wild-type plants in response to bacterial wilt and scab pathogens. CmbHLH87 may be useful for genetic engineering of novel pumpkin cultivars in the future.

Improved Powdery Mildew Resistance of Transgenic Nicotiana benthamiana Overexpressing the Cucurbita moschata CmSGT1 Gene.

Powdery mildew (PM), which is mainly caused by Podosphaera xanthii, is a serious biotrophic pathogen disease affecting field-grown and greenhouse-grown cucurbit crops worldwide. Because fungicides poorly control PM, the development and cultivation of PM-resistant varieties is critical. A homolog of SGT1 (suppressor of the G2 allele of skp1), which encodes a key component of the plant disease-associated signal transduction pathway, was previously identified through a transcriptomic analysis of a PM-resistant pumpkin (Cucurbita moschata) inbred line infected with PM. In this study, we have characterized this SGT1 homolog in C. moschata, and investigated its effects on biotic stress resistance. Subcellular localization results revealed that CmSGT1 is present in the nucleus. Additionally, CmSGT1 expression levels in the PM-resistant material was strongly induced by PM, salicylic acid (SA) and hydrogen peroxide (H2O2). In contrast, SA and H2O2 downregulated CmSGT1 expression in the PM-susceptible material. The ethephon (Eth) and methyl jasmonate (MeJA) treatments upregulated CmSGT1 expression in both plant materials. The constitutive overexpression of CmSGT1 in Nicotiana benthamiana (N. benthamiana) minimized the PM symptoms on the leaves of PM-infected seedlings, accelerated the onset of cell necrosis, and enhanced the accumulation of H2O2. Furthermore, the expression levels of PR1a and PR5, which are SA signaling transduction markers, were higher in the transgenic plants than in wild-type plants. Thus, the transgenic N. benthamiana plants were significantly more resistant to Erysiphe cichoracearum than the wild-type plants. This increased resistance was correlated with cell death, H2O2 accumulation, and upregulated expression of SA-dependent defense genes. However, the chlorosis and yellowing of plant materials and the concentration of bacteria at infection sites were greater in the transgenic N. benthamiana plants than in the wild-type plants in response to infections by the pathogens responsible for bacterial wilt and scab. Therefore, CmSGT1-overexpressing N. benthamiana plants were hypersensitive to these two diseases. The results of this study may represent valuable genetic information for the breeding of disease-resistant pumpkin varieties, and may also help to reveal the molecular mechanism underlying CmSGT1 functions.

Identifying Key Genes of Liver Cancer by Networking of Multiple Data Sets.

Liver cancer is one of the deadliest cancers in the world. To find effective therapies for this cancer, it is indispensable to identify key genes, which may play critical roles in the incidence of the liver cancer. To identify key genes of the liver cancer with high accuracy, we integrated multiple microarray gene expression data sets to compute common differentially expressed genes, which will result more accurate than those from individual data set. To find the main functions or pathways that these genes are involved in, some enrichment analyses were performed including functional enrichment analysis, pathway enrichment analysis, and disease association study. Based on these genes, a protein-protein interaction network was constructed and analyzed to identify key genes of the liver cancer by combining the local and global influence of nodes in the network. The identified key genes, such as TOP2A, ESR1, and KMO, have been demonstrated to be key biomarkers of the liver cancer in many publications. All the results suggest that our method can effectively identify key genes of the liver cancer. Moreover, our method can be applied to other types of data sets to select key genes of other complex diseases.

Collaborative Completion of Transcription Factor Binding Profiles via Local Sensitive Unified Embedding.

Although the newly available ChIP-seq data provides immense opportunities for comparative study of regulatory activities across different biological conditions, due to cost, time or sample material availability, it is not always possible for researchers to obtain binding profiles for every protein in every sample of interest, which considerably limits the power of integrative studies. Recently, by leveraging related information from measured data, Ernst et al. proposed ChromImpute for predicting additional ChIP-seq and other types of datasets, it is demonstrated that the imputed signal tracks accurately approximate the experimentally measured signals, and thereby could potentially enhance the power of integrative analysis. Despite the success of ChromImpute, in this paper, we reexamine its learning process, and show that its performance may degrade substantially and sometimes may even fail to output a prediction when the available data is scarce. This limitation could hurt its applicability to important predictive tasks, such as the imputation of TF binding data. To alleviate this problem, we propose a novel method called Local Sensitive Unified Embedding (LSUE) for imputing new ChIP-seq datasets. In LSUE, the ChIP-seq data compendium are fused together by mapping proteins, samples, and genomic positions simultaneously into the Euclidean space, thereby making their underling associations directly evaluable using simple calculations. In contrast to ChromImpute which mainly makes use of the local correlations between available datasets, LSUE can better estimate the overall data structure by formulating the representation learning of all involved entities as a single unified optimization problem. Meanwhile, a novel form of local sensitive low rank regularization is also proposed to further improve the performance of LSUE. Experimental evaluations on the ENCODE TF ChIP-seq data illustrate the performance of the proposed model. The code of LSUE is available at https://github.com/ekffar/LSUE.

Survival of a newborn from a pregnant woman with rabies infection

Background Rabies is very common in People's Republic of China. Each year thousands of people die because of this disease, but rabies diagnosed in pregnancy is very rare. Case Presentation In this study, we report the case of a pregnant woman who was infected with the rabies virus after a dog bite. The symptoms of rabies appeared in labor and she died after pregnancy. Her baby and husband did not develop the disease. Conclusion The phenomenon that the newborn infant was healthy may be related to the protective role of placenta in resisting the invasion of the rabies virus or the absence of systemic viremia. The prompt administration of vaccines and anti-rabies immunoglobulin to the infant may have also contributed to his survival.(AU)

Survival of a newborn from a pregnant woman with rabies infection

Rabies is very common in Peoples Republic of China. Each year thousands of people die because of this disease, but rabies diagnosed in pregnancy is very rare. Case Presentation In this study, we report the case of a pregnant woman who was infected with the rabies virus after a dog bite. The symptoms of rabies appeared in labor and she died after pregnancy. Her baby and husband did not develop the disease. Conclusion The phenomenon that the newborn infant was healthy may be related to the protective role of placenta in resisting the invasion of the rabies virus or the absence of systemic viremia. The prompt administration of vaccines and anti-rabies immunoglobulin to the infant may have also contributed to his survival.

Characterization and expression profile of CaNAC2 pepper gene.

The plant-specific NAC (NAM, ATAF, and CUC) transcription factors have diverse role in development and stress regulation. A new transcript encoding NAC protein, homologous to nam-like protein 4 from Petunia was identified from an ABA-regulated subtractive cDNA library of Capsicum annuum seedling. Here, this homolog (named CaNAC2) from C. annuum was characterized and investigated its role in abiotic stress tolerance. Our results indicated that a plant-specific and conserved NAC domain was located in the N-terminus domain of CaNAC2 which was predicted to encode a polypeptide of 410 amino acids. Phylogenetic analysis showed that CaNAC2 belonged to the NAC2 subgroup of the orthologous group 4d. The protein CaNAC2 was subcellularly localized in the nucleus and it had transcriptional activity in yeast cell. CaNAC2 was expressed mainly in seed and root. The transcription expression of CaNAC2 was strongly induced by cold, salt and ABA treatment and inhibited by osmotic stress and SA treatment. Silence of CaNAC2 in virus-induced gene silenced pepper seedlings resulted in the increased susceptibility to cold stress and delayed the salt-induced leaf chlorophyll degradation. These results indicated that this novel CaNAC2 gene might be involved in pepper response to abiotic stress tolerance.

[Effect of necrostatin-1 on apoptosis induced by aluminum and its mechanism].

OBJECTIVE: To study the effect of necrostatin (Nec-1) on apoptosis induced by aluminum (Al), and approach the mechanism. METHODS: Neural cell death model was made by 4 mmol/L Al treated neuroblastoma cells (SH-SY5Y). Cell viabilities were detected at different concentrations of Al and/or Nec-1. Hoechst 33342/PI double staining was used to observe apoptosis and (or) necrosis that were quantified by flow cytometry using Annexin V/PI double staining. Apoptotic pathway was tested by activities of Caspase-3, Caspase-8 and Caspase-9. In addition, the expression of NF-kappa B and Cyt-c was measured by immunocytochemistry. RESULTS: Cell viabilities were significantly decreased with the increasing concentrations of Al (P < 0.05), which could be significantly upregulated by 60 micromol/L Nec-1 (P < 0.05) and were correlated with the concentrations of Nec-1 (P < 0.05, P < 0.01). Apoptosis and necrosis were observed under fluorescent microscope and quantified by flow cytometry, which suggested an increasing trend of apoptotic and necrotic rates (P < 0.05, P < 0.01). Whereas, Nec-1 could not only decrease the necrotic rate but also apoptotic rate as well (P < 0.05, P < 0.01). Data of Nec-1 on caspases activities showed that Nec-1 could not affect Caspase-9 activity (P > 0.05) and Cty-c protein expression as well (P > 0.05). However, Nec-1 could reduce Caspase-8 activity significantly (P < 0.05, P < 0.01) and increase NF-kappa B protein expression (P < 0.05, P < 0.01) and finally decrease Caspase-3 activity (P < 0.05). CONCLUSION: Nec-1 could reduce cell apoptosis induced by Al, through Caspase-8 pathway, and up-regulate the expression of NF-kappa B protein.

[The relationship between the genotype of hepatitis B virus and clinical and liver pathological features of infected patients in the Zhoushan Islands, China].

OBJECTIVE: To investigate the relationship between the genotypes of hepatitis B virus and the clinical and liver pathological features of patients with chronic hepatitis in the Zhoushan Islands. METHODS: One hundred eighty HBV DNA positive chronic hepatitis patients with HBV markers were enrolled in this study. They were at least second generation Zhoushan Island residents. One hundred forty-seven of them were males and 33 were females with an average age of 39.0+/-11.3. Among the 180 patients, 17 had ASC, 57 had mild CHB, 48 moderate CHB, 9 severe CHB, 6 SHB, 39 LC, and 4 had HCC. The genotypes of their serum HBV were detected by using PCR integrated with Tagman MGB probe technology, and their serum HBV markers, HBV DNA and liver functions were also examined. Out of 180 patients, 129 accepted a liver biopsy. A pathological evaluation was then performed. RESULTS: HBVs of genotype C, 135 cases (75.0%), of B, 40 cases (22.2%), and of B+C, 5 cases (2.8%) were found among these 180 patients. No genotype A or D HBV were found. The proportions of genotype C virus were 7/17, 86/114, 34/39, 6/6 in ASC, CHB, LC and SHB patients. In the hepatocellular carcinoma patients, there were 2 each of genotype B and C. Among the 99 patients with genotype C HBV, 84 cases (84.8%) showed moderate and severe inflammation histologically in their livers and among the 30 patients with B, 7 cases (23.3%) showed moderate to severe inflammation in their livers (z = 6.47, P less than 0.01). The proportion of genotype C HBV was significantly different from that of genotype B HBV in those that showed moderate and severe (S3-4) liver fibrosis. In patients infected with genotype C HBV who had moderate and severe liver pathological changes, their clinical manifestations reflected better the histological alterations of their livers. CONCLUSION: Genotypes C, B and B+C HBV were found in CHB patients in the Zhoushan Islands of China, and type C was the predominant one. The liver pathological damage level of genotype C HBV infected patients is more serious than that of genotype B.