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51.
Huiyun Li Ye Liu Sumei Chen Jiafu Jiang Aiping Song Weimin Fang Fadi Chen 《Phyton》2020,89(4):851-859
Black spot disease, caused by the necrotrophic fungus Alternaria
tenuissima (Fr.) Wiltsh (A. tenuissima), is considered a highly destructive disease
of Chrysanthemum (Chrysanthemum morifolium Ramat.). A set of 17 accessions
of commercial chrysanthemum cultivars were evaluated for resistance to A.
tenuissima by seedling artificial inoculation. It was found that the reaction of
the accessions to artificial inoculation ranged from resistant to highly susceptible.
Five varieties of chrysanthemum (‘Zhongshan Taogui’, ‘Jinba’, ‘Zhongshan Jinguan’, ‘Jinling Wanhuang’ and ‘Jinling Yangguang’) were resistant; two varieties
of chrysanthemum (‘Zhongshan Xinggui’ and ‘Zhongshan Jinkui’) were moderately resistant; and others were susceptible to various degrees, four varieties of
chrysanthemum (‘Zhongshan Zihe’, ‘Zhongshan Jiuhong’, ‘Zaoyihong’ and ‘Jinling Jiaohuang’) were highly susceptible, especially. Some leaf morphological features of two resistant and two highly susceptible cultivars were further researched.
Trichome density, length, height, gland size and stomata density were found to be
associated with plant passive resistance. Resistant varieties that were identified in
present study will be promising germplasm for exploitation of breeding programmes aimed at developing A. tenuissima-resistant cultivars and increasing
genetic diversity. 相似文献
52.
Wenzhi Jiang Huanbin Zhou Honghao Bi Michael Fromm Bing Yang Donald P. Weeks 《Nucleic acids research》2013,41(20):e188
The type II CRISPR/Cas system from Streptococcus pyogenes and its simplified derivative, the Cas9/single guide RNA (sgRNA) system, have emerged as potent new tools for targeted gene knockout in bacteria, yeast, fruit fly, zebrafish and human cells. Here, we describe adaptations of these systems leading to successful expression of the Cas9/sgRNA system in two dicot plant species, Arabidopsis and tobacco, and two monocot crop species, rice and sorghum. Agrobacterium tumefaciens was used for delivery of genes encoding Cas9, sgRNA and a non-fuctional, mutant green fluorescence protein (GFP) to Arabidopsis and tobacco. The mutant GFP gene contained target sites in its 5′ coding regions that were successfully cleaved by a CAS9/sgRNA complex that, along with error-prone DNA repair, resulted in creation of functional GFP genes. DNA sequencing confirmed Cas9/sgRNA-mediated mutagenesis at the target site. Rice protoplast cells transformed with Cas9/sgRNA constructs targeting the promoter region of the bacterial blight susceptibility genes, OsSWEET14 and OsSWEET11, were confirmed by DNA sequencing to contain mutated DNA sequences at the target sites. Successful demonstration of the Cas9/sgRNA system in model plant and crop species bodes well for its near-term use as a facile and powerful means of plant genetic engineering for scientific and agricultural applications. 相似文献
53.
Xi-Tao Yang Dong-Chao Pan Er-Tao Chen Yong-Yan Bi Dong-Fu Feng 《Neurochemical research》2013,38(10):1996-2008
Stromal cell-derived factor-1α (SDF-1α) plays an important role after injury. However, little is known regarding its temporal and spatial expression patterns or how it interacts with glial cells after optic nerve crush injury. We characterized the temporal and spatial expression pattern of SDF-1α in the retina and optic nerve following optic nerve crush and demonstrated that SDF-1α is localized to the glial cells that are distributed in the retina and optic nerve. CXCR4, the receptor for SDF-1α, is expressed along the ganglion cell layer (GCL). The relative expression levels of Sdf-1α mRNA and SDF-1α protein in the retina and optic nerve 1, 2, 3, 5, 7, 10 and 14 days after injury were determined using real-time polymerase chain reaction (PCR) and enzyme-linked immunosorbent assay, respectively, and the Cxcr4 mRNA expression was determined using real-time PCR. Immunofluorescence and immunohistochemical approaches were used to detect the localization of SDF-1α and CXCR4 after injury. The upregulation of Sdf-1α and Cxcr4 mRNA was detected as early as day one after injury in the retina and day two in the optic nerve, the expression peaks 5–7 days after injury. The expression of Sdf-1α and Cxcr4 mRNA was maintained for at least 14 days after the optic nerve crush injury. Furthermore, SDF-1α-positive zones were distributed locally in the reactive glial cells, which suggested potential autocrine stimulation. CXCR4 was mainly expressed in the GCL, which was also adjacent to the the glial cells. These findings suggest that following optic nerve crush, the levels of endogenous SDF-1α and CXCR4 increase in the retina and optic nerve, where activated glial cells may act as a source of increased SDF-1α protein. 相似文献
54.
Wang Xinhong Liu Weimin Wu Yue Liu Xiaojun Liang Xiao Wan Zhaofei Wang Nanping Yuan Zuyi 《Molecular and cellular biochemistry》2013,377(1-2):131-141
Glycodelin A (GdA) is a dimeric glycoprotein synthesized by the human endometrium under progesterone regulation. Based on the high sequence similarity with β-lactoglobulin, it is placed under the lipocalin superfamily. The protein is one of the local immunomodulators present at the feto-maternal interface which affects both the innate as well as the acquired arms of the immune system, thereby bringing about successful establishment and progression of pregnancy. Our previous studies revealed that the domain responsible for the immunosuppressive activity of glycodelin lies on its protein backbone and the glycans modulate the same. This study attempts to further delineate the apoptosis inducing region of GdA. Our results demonstrate that the stretch of amino acid sequence between Met24 to Leu105 is necessary and sufficient to inhibit proliferation of T cells and induce apoptosis in them. Further, within this region the key residues involved in harboring the activity were shown to be present between Asp52 and Ser65. 相似文献
55.
L. H. Wu Y. J. Liu S. B. Zhou F. G. Guo D. Bi X. H. Guo A. J. M. Baker J. A. C. Smith Y. M. Luo 《Plant Systematics and Evolution》2013,299(3):487-498
Sedum plumbizincicola X.H. Guo et S.B. Zhou ex L.H. Wu (Crassulaceae), a new species restricted to lead–zinc mining areas in Zhejiang Province, China, is described and illustrated. This taxon belongs to sect. Sedum (H. Ohba) S.H. Fu based on the adaxially gibbous carpels and follicles. It superficially resembles S. alfredii Hance and three other Sedum species found in the same area, but differs from these other taxa in bearing 4-merous flowers. Differences in geographical distribution, growth habit, phenology, macromorphology, leaf and stem anatomy, as well as seed micromorphology among S. plumbizincicola, S. alfredii and other related taxa in the genus Sedum are also reported. nrDNA internal transcribed spacers (ITS) sequences from seven populations of S. plumbizincicola support the recognition of this as a taxonomic entity distinct from S. alfredii. 相似文献
56.
In this article, surface coatings derived from homo-bifunctional tri(ethylene glycol) (EG3) and hexa(ethylene glycol) (EG6) molecules which have two terminal aldehyde groups are reported. These homo-bifunctional molecules can be used to functionalize amine-terminated surfaces through crosslinking one aldehyde group to surface amine groups, while leaving the other aldehyde group available for covalent immobilization of proteins. Best of all, after reducing remaining aldehyde groups on the surface with a reducing agent, sodium borohydride, the surface becomes oligo(ethylene glycol) (OEG)-terminated. The OEG-terminated surface can resist nonspecific protein adsorption, a feature that is often required for many biosensors and biomedical devices. Although some mixed self-assembled monolayers formed from two different organothiols also permit covalent protein immobilization and resist nonspecific protein adsorption, the procedure reported herein requires only one type of homo-bifunctional molecule and can be applied to both silicon and gold surfaces. 相似文献
57.
58.
Huahua Wang Junjun Huang Weihong Liang Xiaolei Liang Yurong Bi 《Plant and Soil》2013,366(1-2):479-490
Background and Aims
Polyamines and nitric oxide (NO) are two important molecules modulating numerous environment stresses in plants. This study was to investigate the roles of polyamines and NO in aluminum (Al) tolerance in red kidney bean.Methods
The interaction between putrescine (Put) and NO under Al stress was examined. NO donor and scavenger were used to further examine the role of NO in Al-induced citrate secretion from roots by high performance liquid chromatography.Results
Al stress caused increase of endogenous free Put, and exogenous Put alleviated Al-induced inhibition of root elongation and Al accumulation. In addition, Put induced NO production and nitrate reductase (NR) activity under Al stress. Al- and Put-induced NO production could be reversed by NR inhibitor. Furthermore, Al stress stimulated citrate secretion from roots, and this response was stimulated by NO donor, whereas NO scavenger inhibited Al-induced citrate secretion from roots. Concomitantly, NO donor reduced Al accumulation in root apexes, while NO scavenger further enhanced Al accumulation. Al-induced inhibition of root growth was significantly improved by exogenous citrate treatment.Conclusions
Put and NO enhanced Al tolerance by modulating citrate secretion from roots, and NO may act downstream of Put in red kidney bean under Al stress. 相似文献59.
Faming Wang Weixing Zhu Bi Zou Deborah A. Neher Shenglei Fu Hanping Xia Zhian Li 《Plant and Soil》2013,364(1-2):207-218
Background and aims
The relationship between tree species and soil nutrient availability is critical for evaluating plantation succession and promoting forest restoration. This study was conducted to evaluate the impact of exotic and native tress species on soil nutrient availability.Methods
Four exotic species (Eucalyptus urophylla, E. tereticornis, Acaia auriculaeformis, A. mangium) and four native species (Castanopsis fissa, Schima superba, C. hystrix, Michelia macclurei) were planted and grown for one-year. Soil solution (DOC, DON, NH4?N, NO3?N) was sampled and analyzed during the study. After the experiment, soil properties were determined, and plant tissues were analyzed.Results
DOC levels were greater in soils with trees planted than controls without trees. Compared to native species, exotic species had much faster growth rates and greatly reduced DON and NO3?N concentrations. Exotic species always had less P concentrations in leaves and stems than native species. Furthermore, N-fixing A. auriculaeformis led to greater soil available P compared to other species.Conclusions
Based on these findings, we provide some recommendations for afforestation practice. This study highlights that a better understanding of the pros and cons of exotic species would be beneficial to advance afforestation in China and the world. 相似文献60.
Yuqi Wang Weimin Dai Xiangyang Chu Bo Yang Ming Zhao Yu’e Sun 《Biotechnology letters》2013,35(12):2013-2019
Metformin, which is commonly used as an oral anti-hyperglycemic agent of the biguanide family, may reduce cancer risk and improve prognosis. However, the mechanism by which metformin affects various cancers, including lung cancer, remains unknown. MiR-222 induces cell growth and cell cycle progression via direct targeting of p27, p57 and PTEN in cancer cells. In the present study, we used A549 and NCI-H358 human lung cancer cell lines to study the effects and mechanisms of metformin. Metformin treatment reduced expression of miR-222 in these cells (p < 0.05). As a result, protein abundance of p27, p57 and PTEN were increased in cells exposed to metformin. Therefore, these data provide novel evidence for a mechanism that may contribute to the anti-neoplastic effects of metformin suggested by recent population studies and justifying further work to explore potential roles for it in lung cancer treatment. 相似文献