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MOLECULAR CHARACTERIZATION OF AUTOPHAGY‐RELATED GENE 5 FROM Spodoptera exigua AND EXPRESSION ANALYSIS UNDER VARIOUS STRESS CONDITIONS 下载免费PDF全文
Kai‐Yu Liu Yu‐Qian Xia Jing Zhou Zu‐Wen Chen Dandan Lu Ning‐Zhao Zhang Xu‐Sheng Liu Hui Ai Li‐Lin Zhou 《Archives of insect biochemistry and physiology》2016,92(4):225-241
Autophagy is not only involved in development, but also has been proved to attend immune response against invading pathogens. Autophagy protein 5 (ATG5) is an important autophagic protein, which plays a crucial role in autophagosome elongation. Although ATG5 has been well studied in mammal, yeast, and Drosophila, little is known about ATG5 in lepidopteran insects. We cloned putative SeAtg5 gene from Spodoptera exigua larvae by the rapid amplification of cDNA ends method, and its characteristics and the influences of multiple exogenous factors on its expression levels were then investigated. The results showed that the putative S. exigua SeATG5 protein is highly homologous to other insect ATG5 proteins, which has a conserved Pfm domain and multiple phosphorylation sites. Next, fluorescence microscope observation showed that mCherry‐SeATG5 was distributed in both nucleus and cytoplasm of Spodoptera litura Sl‐HP cells and partially co‐localized with BmATG6‐GFP, but it almost has no significant co‐localization with GFP‐HaATG8. Then, the Western blot analysis demonstrated that GFP‐SeATG5 conjugated with ATG12. Moreover, real‐time PCR revealed that its expression levels significantly increased at the initiation of pupation and the stage of adult. In addition, the expression levels of SeAtg5 can be enhanced by the starvation, UV radiation, and infection of baculovirus and bacterium. However, the expression levels of SeAtg5 decreased at 24 h post treatments in all these treatments except in starvation. These results suggested that SeATG5 might be involved in response of S. exigua under various stress conditions. 相似文献
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A large‐scale phylogeny of the lycophyte genus Selaginella (Selaginellaceae: Lycopodiopsida) based on plastid and nuclear loci 下载免费PDF全文
Xin‐Mao Zhou Carl J. Rothfels Liang Zhang Zhao‐Rong He Timothée Le Péchon Hai He Ngan Thi Lu Ralf Knapp David Lorence Xing‐Jin He Xin‐Fen Gao Li‐Bing Zhang 《Cladistics : the international journal of the Willi Hennig Society》2016,32(4):360-389
The lycophyte genus Selaginella alone constitutes the family Selaginellaceae, the largest of the lycophyte families. The genus is estimated to contain 700–800 species distributed on all continents except Antarctica, with highest species diversity in tropical and subtropical regions. The monophyly of Selaginella in this broad sense has rarely been doubted, whereas its intrageneric classification has been notoriously contentious. Previous molecular studies were based on very sparse sampling of Selaginella (up to 62 species) and often used DNA sequence data from one genome. In the present study, DNA sequences of one plastid (rbcL) and one nuclear (ITS) locus from 394 accessions representing approximately 200 species of Selaginella worldwide were used to infer a phylogeny using maximum likelihood, Bayesian inference and maximum parsimony methods. The study identifies strongly supported major clades and well resolves relationships among them. Major results include: (i) six deep‐level clades are discovered representing the deep splits of Selaginella; and (ii) 20 major clades representing 20 major evolutionary lineages are identified, which differ from one another in molecular, macro‐morphological, ecological and spore features, and/or geographical distribution. 相似文献
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Xiaobei Wang Huaixu Cheng Mingsheng Lu Yaowei Fang Yuliang Jiao Weijuan Li 《Biofouling》2016,32(10):1223-1233
Dental plaque is a biofilm of water-soluble and water-insoluble polysaccharides, produced primarily by Streptococcus mutans. Dextranase can inhibit biofilm formation. Here, a dextranase gene from the marine microorganism Arthrobacter oxydans KQ11-1 is described, and cloned and expressed using E. coli DH5α competent cells. The recombinant enzyme was then purified and its properties were characterized. The optimal temperature and pH were determined to be 60°C and 6.5, respectively. High-performance liquid chromatography data show that the final hydrolysis products were glucose, maltose, maltotriose, and maltotetraose. Thus, dextranase can inhibit the adhesive ability of S. mutans. The minimum biofilm inhibition and reduction concentrations (MBIC50 and MBRC50) of dextranase were 2 U ml?1 and 5 U ml?1, respectively. Scanning electron microscopy and confocal laser scanning microscope (CLSM) observations confirmed that dextranase inhibited biofilm formation and removed previously formed biofilms. 相似文献
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