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941.
Y. Ding W. Wu W. Wei R.E. Davis I.‐M. Lee R.W. Hammond J.P. Sheng L. Shen Y. Jiang Y. Zhao 《The Annals of applied biology》2013,162(1):131-139
Phytoplasmas are phloem‐inhabiting, cell wall‐less bacteria that cause numerous plant diseases worldwide. Plants infected by phytoplasmas often exhibit various symptoms indicative of hormonal imbalance. In this study, we investigated the effects of potato purple top (PPT) phytoplasma infection on gibberellin homeostasis in tomato plants. We found that PPT phytoplasma infection caused a significant reduction in endogenous levels of gibberellic acid (GA3). The decrease in GA3 content in diseased plants was correlated with down regulation of genes responsible for biosynthesis of bioactive GAs ( GA20ox1 and GA3ox1) and genes involved in formation of GA precursors [geranyl diphosphate synthase (GPS) and copalyldiphosphate synthase (CPS)]. Exogenous application of GA3 at 200 µmol L?1 was able to restore the GA content in infected plants to levels comparable to those in healthy controls, and to attenuate the characteristic ‘big bud’ symptoms induced by the phytoplasma. The interesting observation that PPT phytoplasma‐infected plants had prolonged low expression of key GA biosynthesis genes GA20ox1 and GA3ox1 under GA deficiency conditions led us to hypothesise that there was a diminished sensitivity of the GA metabolism feedback regulation, especially GA biosynthesis negative feedback regulation, in those affected plants, and such diminished sensitization in early stages of infection may represent a central element of the phytoplasma‐induced disruption of GA homeostasis and pathogenesis. 相似文献
942.
A novel Gram stain-negative, catalase- and oxidase-positive, strictly aerobic bacterium, designated strain H50T, was isolated from an amphioxus breeding zone in the coastal region of the Yellow Sea, China. Cells were observed to be ovoid or short rods, lacked flagella and were found to contain bacteriochlorophyll a. Poly-beta-hydroxybutyrate was found to be accumulated. The temperature range for growth was determined to be 0–37 °C (optimum 28–37 °C). The halotolerance range for growth is 1–15 % NaCl (optimum 2–7 %). The pH range for growth is 6.0–8.0 (optimum 7.0). The major fatty acids were identified as C18:1ω7c and C16:0. The following polar lipids were found to be present: diphosphatidylglycerol, phosphatidylglycerol and a lipid. The predominant respiratory quinone was determined to be Q-10. DNA G+C content was determined to be 57.7 mol%. Strain H50T exhibited the highest 16S rRNA gene sequence similarity to Pelagicola litoralis DSM 18290T (96.1 %), Roseovarius mucosus DSM 17069T (95.8 %) and Roseovarius tolerans DSM 11457T (95.7 %). In the phylogenetic trees, strain H50T was clustered with the genus Roseovarius but not Pelagicola. On the basis of phenotypic, chemotaxonomic and genotypic data, strain H50T is considered to represent a novel species in the genus Roseovarius, for which the name Roseovarius marisflavi sp. nov. is proposed. The type strain is H50T (=CGMCC 1.10799T=JCM 17553T). 相似文献
943.
Lei Cheng Yi Liu Hua Zhao Wen ZhangYing-Jun Guo Lin Nie 《Biochemical and biophysical research communications》2013
Peripheral nerve injury is often followed by incomplete and unsatisfactory functional recovery and may be associated with sensory and motor impairment of the affected limb. Therefore, a novel method is needed to improve the speed of recovery and the final functional outcome after peripheral nerve injuries. This report investigates the effect of lentiviral-mediated transfer of conserved dopamine neurotrophic factor (CDNF) on regeneration of the rat peripheral nerve in a transection model in vivo. We observed notable overexpression of CDNF protein in the distal sciatic nerve after recombinant CDNF lentiviral vector application. We evaluated sciatic nerve regeneration after surgery using light and electron microscopy and the functional recovery using the sciatic functional index and target muscle weight. HE staining revealed better ordered structured in the CDNF-treated group at 8 weeks post-surgery. Quantitative analysis of immunohistochemistry of NF200 and S-100 in the CDNF group revealed significant improvement of axonal and Schwann cell regeneration compared with the control groups at 4 weeks and 8 weeks after injury. The thickness of the myelination around the axons in the CDNF group was significantly higher than in the control groups at 8 weeks post-surgery. The CDNF group displayed higher muscle weights and significantly increased sciatic nerve index values. Our findings suggest that CDNF gene therapy could provide durable and stable CDNF protein concentration and has the potential to enhance peripheral nerve regeneration, morphological and functional recovery following nerve injury, which suggests a promising strategy for peripheral nerve repair. 相似文献
944.
Yaou Shen Zhou Jiang Sifen Lu Haijian Lin Shibin Gao Huanwei Peng Guangsheng Yuan Li Liu Zhiming Zhang Maojun Zhao Tingzhao Rong Guangtang Pan 《Biochemical and biophysical research communications》2013
Genetic transformation of maize is highly dependent on the development of embryonic calli from the dedifferentiated immature embryo. To better understand the regulatory mechanism of immature embryo dedifferentiation, we generated four small RNA and degradome libraries from samples representing the major stages of dedifferentiation. More than 186 million raw reads of small RNA and degradome sequence data were generated. We detected 102 known miRNAs belonging to 23 miRNA families. In total, we identified 51, 70 and 63 differentially expressed miRNAs (DEMs) in the stage I, II, III samples, respectively, compared to the control. However, only 6 miRNAs were continually up-regulated by more than fivefold throughout the process of dedifferentiation. A total of 87 genes were identified as the targets of 21 DEM families. This group of targets was enriched in members of four significant pathways including plant hormone signal transduction, antigen processing and presentation, ECM-receptor interaction, and alpha-linolenic acid metabolism. The hormone signal transduction pathway appeared to be particularly significant, involving 21 of the targets. While the targets of the most significant DEMs have been proved to play essential roles in cell dedifferentiation. Our results provide important information regarding the regulatory networks that control immature embryo dedifferentiation in maize. 相似文献
945.
Miao Gao Hui Yang Ji Zhao Jun Liu Yan-hua Sun Yu-jiong Wang Jian-guang Sun 《Antonie van Leeuwenhoek》2013,103(3):647-653
A novel Gram-positive, rod-shaped, motile, spore-forming, nitrogen-fixing bacterium, designated strain 112T, was isolated from cabbage rhizosphere in Beijing, China. The strain was found to grow at 10–40 °C and pH 4–11, with an optimum of 30 °C and pH 7.0, respectively. Phylogenetic analysis based on a fragment of the full-length 16S rRNA gene sequence revealed that strain 112T is a member of the genus Paenibacillus. High levels of 16S rRNA gene similarities were found between strain 112T, Paenibacillus sabinae DSM 17841T (97.82 %) and Paenibacillus forsythiae DSM 17842T (97.22 %). However, the DNA–DNA hybridization values between strain 112T and the type strains of these two species were 10.36 and 6.28 %, respectively. The predominant menaquinone was found to be menaquinone 7 (MK-7). The major fatty acids were determined to be anteiso-C15:0 and C16:0. The major polar lipids were found to be diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol and unknown aminophospholipids. The cell wall peptidoglycan was found to contain meso-diaminopimelic acid. The DNA G+C content was determined to be 55.4 mol%. On the basis of its phenotypic characteristics, 16S rRNA gene sequence analysis and the value of DNA–DNA hybridization, strain 112T is considered to represent a novel species of the genus Paenibacillus, for which the name Paenibacillus brassicae sp. nov. is proposed. The type strain is 112T (= ACCC 01125T = DSM 24983T). 相似文献
946.
Lin Xu Yong Zhang Zheng Shan Deng Liang Zhao Xiu Li Wei Ge Hong Wei 《Antonie van Leeuwenhoek》2013,103(3):559-565
During a study of the diversity and phylogeny of rhizobia isolated from root nodules of Oxytropis ochrocephala grown in the northwest of China, four strains were classified in the genus Rhizobium on the basis of their 16S rRNA gene sequences. These strains have identical 16S rRNA gene sequences, which showed a mean similarity of 94.4 % with the most closely related species, Rhizobium oryzae. Analysis of recA and glnA sequences showed that these strains have less than 88.1 and 88.7 % similarity with the defined species of Rhizobium, respectively. The genetic diversity revealed by ERIC-PCR fingerprinting indicated that the isolates correspond to different strains. Strain CCNWQLS01T contains Q-10 as the predominant ubiquinone. The major fatty acids were identified as feature 8 (C18: 1ω7c and/or C18: 1ω6c; 67.2 %). Therefore, a novel species Rhizobium qilianshanense sp. nov. is proposed, and CCNWQLS01T (= ACCC 05747T = JCM 18337T) is designated as the type strain. 相似文献
947.
Tao Fang Wang Heng Wang Ai Fen Peng Qing Feng Luo Zhi Li Liu Rong Ping Zhou Song Gao Yang Zhou Wen Zhao Chen 《Biochemical and biophysical research communications》2013
FASN plays an important role in the malignant phenotype of various tumors. Our previous studies show that inhibition FASN could induce apoptosis and inhibit proliferation in human osteosarcoma (OS) cell in vivo and vitro. The aim in this study was to investigate the effect of inhibition FASN on the activity of HER2/PI3K/AKT axis and invasion and migration of OS cell. The expression of FASN, HER2 and p-HER2(Y1248) proteins was detected by immunohistochemistry in OS tissues from 24 patients with pulmonary metastatic disease, and the relationship between FASN and p-HER2 as well as HER2 was investigated. The results showed that there was a positive correlation between FASN and HER2 as well as p-HER2 protein expression. The U-2 OS cells were transfected with either the FASN specific RNAi plasmid or the negative control RNAi plasmid. FASN mRNA was measured by RT-PCR. Western blot assays was performed to examine the protein expression of FASN, HER2, p-HER2(Y1248), PI3K, Akt and p-Akt (Ser473). Migration and invasion of cells were investigated by wound healing and transwell invasion assays. The results showed that the activity of HER2/PI3K/AKT signaling pathway was suppressed by inhibiting FASN. Meanwhile, the U-2OS cells migration and invasion were also impaired by inhibiting the activity of FASN/HER2/PI3K/AKT. Our results indicated that inhibition of FASN suppresses OS cell invasion and migration via down-regulation of the “HER2/PI3K/AKT” axis in vitro. FASN blocker may be a new therapeutic strategy in OS management. 相似文献
948.
Wei-hui Wu Qian Liu Xun Sun Ji-sheng Yu De-sheng Zhao Ye-ping Yu Jun-jie Luo Jia Hu Zhi-wu Yu Yu-fen Zhao Yan-mei Li 《Biochemical and biophysical research communications》2013
Amyloid-β (Aβ) peptides can exist in distinct forms including monomers, oligomers and fibrils, consisting of increased numbers of monomeric units. Among these, Aβ oligomers are implicated as the primary toxic species as pointed by multiple lines of evidence. It has been suggested that toxicity could be rendered by the soluble higher-molecular-weight (high-n) Aβ oligomers. Yet, the most culpable form in the pathogenesis of Alzheimer’s disease (AD) remains elusive. Moreover, the potential interaction among the insoluble fibrils that have been excluded from the responsible aggregates in AD development, Aβ monomers and high-n oligomers is undetermined. Here, we report that insoluble Aβ fibrillar seeds can interact with Aβ monomers at the stoichiometry of 1:2 (namely, each Aβ molecule of seed can bind to two Aβ monomers at a time) facilitating the fibrillization by omitting the otherwise mandatory formation of the toxic high-n oligomers during the fibril maturation. As a result, the addition of exogenous Aβ fibrillar seeds is seen to rescue neuronal cells from Aβ cytotoxicity presumably exerted by high-n oligomers, suggesting an unexpected protective role of Aβ fibrillar seeds. 相似文献
949.
Linlin Zhao Hao Guo Hong Chen Robert B. Petersen Ling Zheng Anlin Peng Kun Huang 《Biochemical and biophysical research communications》2013
Endoplasmic reticulum (ER) stress is associated with the development of diabetes. The present study sought to investigate the effect of Liraglutide, a glucagon like peptide 1 analogue, on ER stress in β-cells. We found that Liraglutide protected the pancreatic INS-1 cells from thapsigargin-induced ER stress and the ER stress associated cell apoptosis, mainly by suppressing the PERK and IRE1 pathways. We further tested the effects of Liraglutide in the Akita mouse, an ER-stress induced type 1 diabetes model. After administration of Liraglutide for 8 weeks, p-eIF2α and p-JNK were significantly decreased in the pancreas of the Akita mouse, while the treatment showed no significant impact on the levels of insulin of INS-cells. Taken together, our findings suggest that Liraglutide may protect pancreatic cells from ER stress and its related cell death. 相似文献
950.
Zheng Liu Ning Sun Shangjun Yang Yanhong Zhao Xiaoqin Wang Xingyu Hao Zhijun Qiao 《Biologia》2013,68(4):577-586
Compared with C3 plants, C4 plants possess a mechanism to concentrate CO2 around the ribulose-1,5-bisphosphate carboxylase/oxygenase in chloroplasts of bundle sheath cells so that the carboxylation reaction work at a much more efficient rate, thereby substantially eliminate the oxygenation reaction and the resulting photorespiration. It is observed that C4 photosynthesis is more efficient than C3 photosynthesis under conditions of low atmospheric CO2, heat, drought and salinity, suggesting that these factors are the important drivers to promote C4 evolution. Although C4 evolution took over 66 times independently, it is hypothesized that it shared the following evolutionary trajectory: 1) gene duplication followed by neofunctionalization; 2) anatomical and ultrastructral changes of leaf architecture to improve the hydraulic systems; 3) establishment of two-celled photorespiratory pump; 4) addition of transport system; 5) co-option of the duplicated genes into C4 pathway and adaptive changes of C4 enzymes. Based on our current understanding on C4 evolution, several strategies for engineering C4 rice have been proposed to increase both photosynthetic efficiency and yield significantly in order to avoid international food crisis in the future, especially in the developing countries. Here we summarize the latest progresses on the studies of C4 evolution and discuss the strategies to introduce two-celled C4 pathway into rice. 相似文献