Synergism Among the Four Tobacco Bushy Top Disease Casual Agents in Symptom Induction and Aphid Transmission.

Tobacco bushy top disease (TBTD), caused by multiple pathogens including tobacco bushy top virus (TBTV), tobacco vein distorting virus (TVDV), TBTV satellite RNA (TBTVsatRNA), and TVDV-associated RNA (TVDVaRNA), is a destructive disease in tobacco fields. To date, how these causal agents are co-transmitted by aphid vectors in field and their roles in disease symptom induction remain largely unknown, due mainly to the lack of purified causal agents. In this study, we have constructed four full-length infectious clones, representing the Yunnan Kunming isolates of TVDV, TBTV, TBTVsatRNA, and TVDVaRNA (TVDV-YK, TBTV-YK, TBTVsatRNA-YK, and TVDVaRNA-YK), respectively. Co-inoculation of these four causal agents to tobacco K326 plants caused typical TBTD symptoms, including smaller leaves, necrosis, and plant stunting. In addition, inoculation of tobacco K326 plants with TBTV alone caused necrosis in systemic leaves by 7 dpi. Tobacco K326 and Nicotiana benthamiana plants infected by single virus or multiple viruses showed very different disease symptoms at various dpi. RT-PCR results indicated that co-infection of TVDVaRNA-YK could increase TVDV-YK or TBTV-YK accumulation in N. benthamiana plants, suggesting that TVDVaRNA-YK can facilitate TVDV-YK and TBTV-YK replication and/or movement in the infected plants. Aphid transmission assays showed that the successful transmission of TBTV-YK, TBTVsatRNA-YK, and TVDVaRNA-YK by Myzus persicae depended on the presence of TVDV-YK, while the presence of TBTVsatRNA-YK increased the aphid transmission efficiency of TBTV and TVDV. We consider that these four new infectious clones will allow us to further dissect the roles of these four causal agents in TBTD induction as well as aphid transmission.

Gene Model Related to m6A Predicts the Prognostic Effect of Immune Infiltration on Head and Neck Squamous Cell Carcinoma.

Head and neck squamous cell carcinoma (HNSCC) is a highly aggressive solid tumor. Because most studies have focused on the intrinsic carcinogenic pathways of tumors, we focused on the relationship between N6-methyladenosine (m6A) and the prognosis of HNSCC in the tumor immune microenvironment. We downloaded RNA-seq data from the TCGA dataset and used univariate Cox regression to screen m6A-related lncRNAs. The expression value of LASSO-screened genes was the sum of LASSO regression coefficients. We then evaluated relationships between the risk score and cellular components or cellular immune response. Differences in immune response under various algorithms were visualized with heat maps. The GSVA package in R was used to analyze GO, BP, KEGG, and hallmark gene sets of immune checkpoint clusters and immune checkpoint scores. The GSEA analysis was performed with the cluster profile package, yielding 21 m6A genes. Related lncRNAs were screened with Pearson's correlations, and the resulting 442 lncRNAs were screened using single-factor analysis. Eight lncRNAs closely related to prognosis were identified through survival random forest. Survival analysis showed that patients with a high risk score had a poor prognosis. Low- and high-risk-score groups differed significantly in m6A gene expression. Prognostic scores from different algorithms were significantly correlated with B cells, T cells, and memory cells in the immune microenvironment. Expression of immune checkpoints and signal pathways differed significantly across risk-score groups, suggesting that m6A could mediate lncRNA-induced immune system dysfunction and affect HNSCC development. A comprehensive study of tumor-cell immune characteristics should provide more insight into the complex immune microenvironment, thus contributing to the development of new immunotherapeutic agents.

The occurrence of Pea enation mosaic virus 1 and Pea enation mosaic virus 2 from disease-affected pea fields in China.

Pea (Pisum sativum L.) is an economically important legume crop that is commonly used as dry beans, fresh peas, pods and shoots (Guo et al. 2009). Pea enation mosaic is an important virus disease of pea caused by two viruses in an obligate symbiosis, pea enation mosaic virus 1 (PEMV-1, Enamovirus, Luteoviridae) and pea enation mosaic virus 2 (PEMV-2, Umbravirus, Tombusviridae) (Hema et al. 2014). In November 2019, foliar yellow mosaic and vein enations symptoms were observed from pea plants in five fields of Honghe autonomous prefecture, Yunnan province, China. Incidence of symptomatic plants ranged from 20 to 40% and was distributed in both small and large fields. Leaves with typical virus-like symptoms were collected from five symptomatic pea plants in two fields and used for total RNA extraction. The five extracts of equimolar quantities were pooled into a sample and subjected to High Throughput Sequencing (HTS) by Illumina HiSeq system. Analyses of raw RNA reads were performed using CLC Genomics Workbench 12 (Qiagen). A total of 60,009,746 RNA reads were obtained from the sample, and de novo assembly of the reads using the CLC Genomics generated 88,105 contigs. BLASTN searches revealed the presence of contigs with high similarities to PEMV-1, PEMV-2, Pea seed-borne mosaic virus, and Bean yellow mosaic virus. To confirm the presence of PEMV-1 and PEMV-2 in the samples, two virus-specific primer pairs were designed based on the contig sequences obtained by HTS in this study. Primer pairs PEMV-1F/PEMV-1R (5'-ATGCCGACTAGATCGAAATC-3'/5'-TCAGAGGGAGGCATTCATTA-3') that flank the cp gene of PEMV-1 and PEMV-2F/PEMV-2R (5'-ATGACGATAATCATTAATG-3'/5'-TCACCCGTAGTGAGAGGCA-3') that target the ORF3 region of PEMV-2 were used to amplify the two viruses in RT-PCR. DNA fragments of the expected sizes (PEMV-1, 570 bp; PEMV-2, 693 bp) were amplified from all five samples. The RT-PCR products were cloned and sequenced. Sequence analysis showed that the 570-bp amplicon (MT481989) shared the highest nucleotide sequence identity of 98.95% with PEMV-1 (Z48507), while the 693-bp fragment (MT481990) had the highest nucleotide sequence identity of 97.4% with PEMV-2 isolate JKI (MK948534). One gram of the symptomatic leaves from each of the five plants was homogenized with 5 mL of 0.01 M phosphate-buffered saline (PBS buffer), pH 7.0. Each of the resulted saps was used to inoculate onto five healthy pea seedlings. A total of 25 healthy pea seedlings were inoculated, and 16 inoculated plants developed yellowing and mottling at 10 days post inoculation (dpi); no symptoms were observed on control plants inoculated only with PBS buffer. The formation of the typical enation was observed along the veins of lower side of the symptomatic leaves of the inoculated plants at 30 dpi. PEMV-1 and PEMV-2 infection were confirmed by RT-PCR assays using the specific primer pairs described above. Although the presence of the pea enation mosaic virus complex was suspected in China based on symptomatology (Brunt et al. 1997), to our knowledge, this is the first molecular confirmation of PEMV-1 and PEMV-2 occurrence in China. The co-infection of PEMV-1 and PEMV-2 usually cause severe yield losses; therefore, integration of detection and control measures is important in pea production regions where the two viruses occurred.

Big Data-Based Identification of Multi-Gene Prognostic Signatures in Liver Cancer.

Simultaneous identification of multiple single genes and multi-gene prognostic signatures with higher efficacy in liver cancer has rarely been reported. Here, 1,173 genes potentially related to the liver cancer prognosis were mined with Coremine, and the gene expression and survival data in 370 samples for overall survival (OS) and 319 samples for disease-free survival (DFS) were retrieved from The Cancer Genome Atlas. Numerous survival analyses results revealed that 39 genes and 28 genes significantly associated with DFS and OS in liver cancer, including 18 and 12 novel genes that have not been systematically reported in relation to the liver cancer prognosis, respectively. Next, totally 9,139 three-gene combinations (including 816 constructed by 18 novel genes) for predicting DFS and 3,276 three-gene combinations (including 220 constructed by 12 novel genes) for predicting OS were constructed based on the above genes, and the top 15 of these four parts three-gene combinations were selected and shown. Moreover, a huge difference between high and low expression group of these three-gene combination was detected, with median survival difference of DFS up to 65.01 months, and of OS up to 83.57 months. The high or low expression group of these three-gene combinations can predict the longest prognosis of DFS and OS is 71.91 months and 102.66 months, and the shortest is 6.24 months and 13.96 months. Quantitative real-time polymerase chain reaction and immunohistochemistry reconfirmed that three genes F2, GOT2, and TRPV1 contained in one of the above combinations, are significantly dysregulated in liver cancer tissues, low expression of F2, GOT2, and TRPV1 is associated with poor prognosis in liver cancer. Overall, we discovered a few novel single genes and multi-gene combinations biomarkers that are closely related to the long-term prognosis of liver cancer, and they can be potential therapeutic targets for liver cancer.

Studies on the interaction of tricyclazole with beta-cyclodextrin and human serum albumin by spectroscopy.

The interaction of tricyclazole (TCZ) with beta-cyclodextrin (beta-CD) and human serum albumin (HSA) were studied by fluorescence spectrum, UV-visible spectrum and second-order scattering technology. It was shown that TCZ has quite a strong ability to quench the fluorescence launching from HSA by reacting with it and forming a certain kind of new compound. The quenching and the energy transfer mechanisms were discussed, respectively. The binding constants and thermodynamic parameters at four different temperatures, the binding locality, and the binding power were obtained. The conformation of HSA was discussed by synchronous and three-dimensional fluorescence techniques. The inclusion reaction between beta-CD and TCZ was explored by scattering method, the inclusion constants and the thermodynamic parameters at 297 K and 311 K were figured out, respectively. The mechanism of inclusion reaction was speculated and linkage among the toxicity of TCZ, the exterior environment and its concentration was attempted to explain on molecule level.

Transcriptional regulation and characterization of the promoter region of the human ABCC6 gene.

ABCC6, a member of the adenosine 5'-triphosphate-binding cassette family of genes, encodes multidrug resistance-associated protein 6, a putative transmembrane transporter expressed primarily in the liver and to a significantly lower extent in other tissues. Mutations in ABCC6 result in pseudoxanthoma elasticum, a multi-system heritable connective tissue disorder with variable phenotypic expression. To examine the transcriptional regulation and tissue-specific expression of this gene, we cloned 2.6 kb of human ABCC6 promoter and developed a series of 5'-deletion constructs linked to luciferase reporter gene. Transient transfections in a number of cultured cell lines of diverse origin identified a specific NF-kappaB-like sequence (-235/-226), which conferred high level of expression in HepG2 hepatoma cells, inferring liver specificity. The functionality of the promoter fragments was confirmed in vivo by tail vein injection followed by luciferase reporter assay. Testing of selected cytokines revealed that transforming growth factor (TGF)-beta upregulated, while tumor necrosis factor (TNF)-alpha and interferon (IFN)-gamma downregulated the promoter activity in HepG2 cells. The responsiveness to TGF-beta was shown to reside primarily within an Sp1/Sp3 cognate-binding site at -58 to -49. The expression of the ABCC6 promoter was also shown to be markedly enhanced by Sp1 protein, as demonstrated by cotransfection of ABCC6 promoter-luciferase constructs and an Sp1 expression vector in Drosophila SL2 cells, which are devoid of endogenous Sp1. Furthermore, four additional transcription factors, with their cognate-binding sequences present in DNA, were shown to bind the 2.6-kb promoter fragment by protein/DNA array. Collectively, the results indicate that human ABCC6 displays tissue-specific gene expression, which can be modulated by proinflammatory cytokines. These findings may have implications for phenotypic expression of heritable and acquired diseases involving abnormality in the ABCC6 gene.

Targeted ablation of the abcc6 gene results in ectopic mineralization of connective tissues.

Pseudoxanthoma elasticum (PXE), characterized by connective tissue mineralization of the skin, eyes, and cardiovascular system, is caused by mutations in the ABCC6 gene. ABCC6 encodes multidrug resistance-associated protein 6 (MRP6), which is expressed primarily in the liver and kidneys. Mechanisms producing ectopic mineralization as a result of these mutations remain unclear. To elucidate this complex disease, a transgenic mouse was generated by targeted ablation of the mouse Abcc6 gene. Abcc6 null mice were negative for Mrp6 expression in the liver, and complete necropsies revealed profound mineralization of several tissues, including skin, arterial blood vessels, and retina, while heterozygous animals were indistinguishable from the wild-type mice. Particularly striking was the mineralization of vibrissae, as confirmed by von Kossa and alizarin red stains. Electron microscopy revealed mineralization affecting both elastic structures and collagen fibers. Mineralization of vibrissae was noted as early as 5 weeks of age and was progressive with age in Abcc6(-/-) mice but was not observed in Abcc6(+/-) or Abcc6(+/+) mice up to 2 years of age. A total body computerized tomography scan of Abcc6(-/-) mice revealed mineralization in skin and subcutaneous tissue as well as in the kidneys. These data demonstrate aberrant mineralization of soft tissues in PXE-affected organs, and, consequently, these mice recapitulate features of this complex disease.

Periplakin gene targeting reveals a constituent of the cornified cell envelope dispensable for normal mouse development.

The members of the plakin family of proteins serve as epidermal cytolinkers and components of cell-cell and cell-matrix adhesion complexes, i.e., desmosomes and hemidesmosomes, respectively. Periplakin is a recently characterized member of this family. Human and mouse periplakin genomic loci are conserved, and the proteins are highly homologous, suggesting a role for periplakin in vertebrate physiology. In order to evaluate the functional role of periplakin, we generated periplakin null mice through targeted homologous recombination of mouse embryonic stem cells, followed by development of Ppl(-/-) mice. Mice homozygous for the targeted allele were born in the expected Mendelian frequency, developed normally, possessed grossly normal epidermis and hair, and were healthy and fertile. The epidermal barrier appeared to develop normally during fetal days E15.5 to E16.5, and the cornified envelope and desmosomes in the newborn mice were ultrastructurally normal. No compensatory increase in the expression of other epithelial proteins was detected in the neonatal mouse epidermis lacking periplakin. Consequently, the primary role of periplakin may not relate to the physiology of the cornified cell envelope in epidermal keratinocytes but may reside in the challenges, which normal laboratory mice do not encounter.

[Analysis of serological findings and clinical manifestations of TORCH infections in newborns].

BACKGROUND: To search for the serological findings and early clinical manifestations as evidences for prevention and treatment TORCH infections in pregnant women and newborns as early as possible. METHODS: ELASA was performed to screen specific anti-TORCH (Toxoplasma gondii, Cytomegalovirus, Rubella virus, Herpes simplex virus) Ig-M antibodies. RESULTS: Totally 1,554 in-patients who were treated in Neonatal Intensive Care Unit (NICU) of our hospital from January 2000 to January 2003 were retrospectively studied, 48 of them had TORCH infections. Cytomegalovirus (CMV), rubella and herpes simplex virus infections accounted for 52.1%, 33.3% and 14.6%, respectively. None of them had toxoplasma infection. CONCLUSION: TORCH infections can cause multiorgan lesions, such as hearing impairment, hyperbilirubinemias and liver dysfunction, impairment of neurologic system, myocardial impairment, thrombocytopenia, and congenital heart disease.Rubella vaccine inoculation, serological screening during pregnancy and early period of newborn, intervention and treatment in the early period are most important.