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81.
82.
Palaeoxenus sinensis Chang, Muona & Teräväinen sp. nov. (Coleoptera, Eucnemidae) is described on the basis of a Cretaceous larva found from the Yixian Formation in Huangbanjigou, Liaoning Province, China. The only previously known member of this clade is a southern Californian endemic, Dohrn's elegant eucnemid beetle (Palaeoxenus dohrni), a species that develops in conifers, especially the incense cedar (Calocedrus decurrens). The new find proves that the highly specialized main eucnemid lineages had evolved 123 Mya, before the main radiation of the angiosperms and probably as an adaptation to development in gymnosperms.  相似文献   
83.
YB1 is a negative regulator in liver fibrosis. We wondered whether SJYB1, a homologous protein of YB1 from Schistosoma japonicum, has an effect on liver fibrosis in vitro. Recombinant SJYB1 (rSJYB1) protein was expressed in a bacterial system and purified by Ni‐NTA His·Bind Resin. A human hepatic stellate cell line, the LX‐2 cell line, was cultured and treated with rSJYB1. The role of rSJYB1 on LX‐2 cells was then analysed by Western blot and luciferase assay. We succeeded in expressing and purifying SJYB1 in a bacterial system and the purified rSJYB1 could be recognized by S japonicum‐infected rabbit sera. Western bolt analysis showed that rSJYB1 inhibited the expression of collagen type I, but had little effect on α‐smooth muscle actin (α‐SMA). Further analysis revealed that rSJYB1 inhibited the activity of collagen α1 (I) (COL1A1) promoter and functioned at ?1592/?1176 region of COL1A1 promoter. Our data demonstrate that rSJYB1‐mediated anti‐fibrotic activity involves inhibiting the activity of COL1A1 promoter and subsequently suppressing the expression of collagen type I in hepatic stellate cells.  相似文献   
84.
This study aimed to examine miR‐140 expression in clinical samples from tuberculosis (TB) patients and to explore the molecular mechanisms of miR‐140 in host‐bacterial interactions during Mycobacterium tuberculosis (M tb) infections. The miR‐140 expression and relevant mRNA expression were detected by quantitative real‐time PCR (qRT‐PCR); the protein expression levels were analysed by ELISA and western blot; M tb survival was measured by colony formation unit assay; potential interactions between miR‐140 and the 3′ untranslated region (UTR) of tumour necrosis factor receptor‐associated factor 6 (TRAF6) was confirmed by luciferase reporter assay. MiR‐140 was up‐regulated in the human peripheral blood mononuclear cells (PBMCs) from TB patients and in THP‐1 and U937 cells with M tb infection. Overexpression of miR‐140 promoted M tb survival; on the other hand, miR‐140 knockdown attenuated M tb survival. The pro‐inflammatory cytokines including interleukin 6, tumour necrosis‐α, interleukin‐1β and interferon‐γ were enhanced by M tb infection in THP‐1 and U937 cells. MiR‐140 overexpression reduced these pro‐inflammatory cytokines levels in THP‐1 and U937 cells with M tb infection; while knockdown of miR‐140 exerted the opposite actions. TRAF6 was identified to be a downstream target of miR‐140 and was negatively modulated by miR‐140. TRAF6 overexpression increased the pro‐inflammatory cytokines levels and partially restored the suppressive effects of miR‐140 overexpression on pro‐inflammatory cytokines levels in THP‐1 and U937 cells with M tb infection. In conclusion, our results implied that miR‐140 promoted M tb survival and reduced the pro‐inflammatory cytokines levels in macrophages with M tb infection partially via modulating TRAF6 expression.  相似文献   
85.
Issue Section: Editorial Journal of Plant Ecology (JPE) was founded in 2008. It is sponsored by the Botanical Society of China and the Institute of Botany, Chinese Academy of Sciences, and published by Oxford University Press, UK. JPE publishes diverse types of articles that fall into the broad scope of plant ecology, including plant ecophysiology, population ecology, community ecology, ecosystem ecology, landscape ecology, conservation ecology, evolutionary ecology, theoretical ecology and global change ecology.  相似文献   
86.
Zhou F  Wu G  Deng W  Pu Y  Wei C  Li Y 《FEBS letters》2007,581(1):34-40
Yeast two-hybrid and coimmunoprecipitation assays indicated that P8, an outer capsid protein of Rice dwarf phytoreovirus (RDV), interacts with rice glycolate oxidase (GOX), a typical enzyme of peroxisomes. Confocal immunofluorescence microscopy revealed that P8 was colocalized with GOX in peroxisomes. Time course analysis demonstrated that the localization of P8 in Spodoptera frugiperda cells changed from diffuse to discrete, punctuate inclusions during expression from 24 to 48 h post inoculation. Coexpression of GOX with P8 may target P8 into peroxisomes, which serve as replication sites for a number of viruses. Therefore, we conclude that the interaction of P8 with the GOX of host cells leads to translocation of P8 into peroxisomes and we further propose that the interaction between P8 and GOX may play important roles in RDV targeting into the replication site of host cells. Our findings have broad significance in studying the mechanisms whereby viruses target appropriate replication sites and begin their replication.  相似文献   
87.
88.
Non-small-cell lung cancer (NSCLC) is one of the main causes of death induced by cancer globally. However, the molecular aberrations in NSCLC patients remain unclearly. In the present study, four messenger RNA microarray datasets (GSE18842, GSE40275, GSE43458, and GSE102287) were downloaded from the Gene Expression Omnibus (GEO) database. Differentially expressed genes (DEGs) between NSCLC tissues and adjacent lung tissues were obtained from GEO2R and the overlapping DEGs were identified. Moreover, functional and pathway enrichment were performed by Funrich, while the protein–protein interaction (PPI) network construction were obtained from STRING and hub genes were visualized and identified by Cytoscape software. Furthermore, validation, overall survival (OS) and tumor staging analysis of selected hub genes were performed by GEPIA. A total of 367 DEGs (95 upregulated and 272 downregulated) were obtained through gene integration analysis. The PPI network consisted of 94 nodes and 1036 edges in the upregulated DEGs and 272 nodes and 464 edges in the downregulated DEGs, respectively. The PPI network identified 46 upregulated and 27 downregulated hub genes among the DEGs, and six (such as CENPE, NCAPH, MYH11, LRRK2, HSD17B6, and A2M) of that have not been identified to be associated with NSCLC so far. Moreover, the expression differences of the mentioned hub genes were consistent with that in lung adenocarcinoma and lung squamous cell carcinoma in the TCGA database. Further analysis showed that all the six hub genes were associated with tumor staging except MYH11, while only the upregulated DEG CENPE was associated with the worse OS of patients with NSCLC. In conclusion, the current study showed that CENPE, NCAPH, MYH11, LRRK2, HSD17B6, and A2M might be the key genes contributed to tumorigenesis or tumor progression in NSCLC, further functional study is needed to explore the involved mechanisms.  相似文献   
89.
Long noncoding RNA (lncRNA) differentiation antagonizing nonprotein coding RNA (DANCR) has been identified as an oncogene in several cancers. However, the biological function and role of DANCR in hepatocellular carcinoma (HCC) remain unclear. Our current study aimed to investigate the detailed mechanism of DANCR in HCC. We found that DANCR was significantly upregulated in HCC cell lines in comparison to LO2 cells. Then, we observed that knockdown of DANCR could greatly inhibit Huh7 and HepG2 cell proliferation. In addition, HCC cell apoptosis was increased by silence of DANCR and meanwhile, cell cycle progression was blocked in G1 phase. Apart from these, downregulation of DANCR repressed HCC cell migration and invasion ability obviously. As predicted by the bioinformatics analysis, microRNA-216a-5p (miR-216a-5p) could serve as a direct target of DANCR. MiR-216a-5p has been reported to be involved in many cancers. Here, the correlation between miR-216a-5p and DANCR was confirmed using dual-luciferase reporter assay and radioimmunoprecipitation assay. Subsequently, Kruppel-like factor 12 (KLF12) exerts an important role in different tumor types. KLF12 can function as a downstream target of miR-216a-5p. Finally, the in vivo experiments were used and the data proved that DANCR also strongly suppressed HCC tumor growth in vivo via targeting miR-216a-5p and KLF12. In conclusion, our study indicated that DANCR might provide a new perspective for HCC treatment.  相似文献   
90.
This study aims to figure out the methylation of long non-coding RNA GAS5 promoter in cervical cancer and the mechanism of GAS5 on the progression of cervical cancer cells. The expression of GAS5 and methylation state of GAS5 in cervical cancer tissues and cells were determined. With the aim to to explore the ability of GAS5 in the proliferation, cell cycle progression, apoptosis, invasion, migration as well as the tumor growth, and metastasis in nude mice were determined. The expression of GAS5 was decreased and methylation state of GAS5 was elevated in cervical cancer. Overexpression of GAS5 inhibited proliferation, cell cycle progression, invasion, migration while inducing apoptosis of cervical cancer cells as well as suppressed tumor growth and metastasis in nude mice. Our study demonstrates that abnormal methylation of GAS5 contributes to poor expression of GAS5 in cervical cancer. In addition, upregulation of GAS5 inhibits the cervical cancer development.  相似文献   
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