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6 results on '"Y. H. Xuan"'

1. Effect of brassinosteroids on ammonium uptake via regulation of ammonium transporter and N-metabolism genes in Arabidopsis

Author

B. T. Zhao, X. F. Zhu, J. H. Jung, and Y. H. Xuan

Subjects
brassinosteroid signaling transcription factor, glutamate synthase, glutamine synthetase, mutant, Biology (General), QH301-705.5, Plant ecology, QK900-989
Abstract

Several studies have been performed to elucidate the role of brassinosteroids (BRs) in plant growth and development. However, information on the role of BR signaling in nutrient uptake is limited. This study explores the relationship between BRs and ammonium transporter 1 (AMT1) expression in Arabidopsis roots. We found that BR treatment reduced the expression of AMT1 genes and that a BR receptor BRI1 mutant bri1-5 reversed its BR-repressed expression. Furthermore, the BR signaling transcription factor, BES1, regulates AMT1 expression in roots. NH4 +-mediated repression of AMT1;1, AMT1;2, and AMT1;3 was suppressed in a gain-of-function BES1 mutant (bes1-D). This mutant was more sensitive to methyl-ammonium and contained a higher ammonium content compared to wild-type plants. However, BES1 failed to bind E-box elements present in the promoter region of the AMT1 genes. Furthermore, NH4 +-mediated glutamine synthetase (GS) and glutamine oxoglutarate aminotransferase (GOGAT) gene expressions were partially inhibited, and GS activity was slightly lower in the bes1-D mutant relative to that observed in wild-type En2 roots. NH4 +-mediated AMT1 suppressions are known to be caused by N-metabolites rather than NH4 + itself, and glutamine application inhibited AMT1 expression in both En2 and bes1-D indicating that BES1 activation inhibited NH4 +-mediated GS/GOGAT induction, which might in turn inhibit AMT1 repression. In conclusion, the present study demonstrates that BR regulated nitrogen uptake and assimilation via the BR signaling pathway.

Published
2016
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3. EFFICACY OF PENICILLIUM CHRYSOGENUM STRAIN SNEF1216 AGAINST ROOT-KNOT NEMATODES (MELOIDOGYNE INCOGNITA) IN CUCUMBER (CUCUMIS SATIVUS L.) UNDER GREENHOUSE CONDITIONS

Author

H. Y. Fan, X. Y. Liu, A. Javeed, Y. H. Xuan, A. Sikandar, M. F. Iqbal, M. Ahmed, X. F. Zhu, M. Y. Zhang, Y. X. Duan, Y. Y. Wang, and L. J. Chen

Subjects
biology, business.industry, Pest control, Biological pest control, Greenhouse, Penicillium chrysogenum, biology.organism_classification, Horticulture, Germination, Meloidogyne incognita, Natural enemies, business, Agronomy and Crop Science, Cucumis, Ecology, Evolution, Behavior and Systematics
Published
2019
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4. IDENTIFICATION AND PHYLOGENETIC ANALYSIS OF NINE CYST NEMATODE POPULATIONS FROM MAIN FIELD CROPS IN CHINA.

Author

Y. X. Feng, D. Wang, Y. H. Xuan, L. J. Chen, Y. Y. Wang, X. Y. Liu, Y. Chen, X. P. Lu, X. F. Zhu, and Y. X. Duan

Subjects
NEMATODES, PHYLOGENY, CROPS, CYSTS (Pathology), POLYMERASE chain reaction
Abstract

Cyst-forming nematodes, a major category of plant parasitic nematodes, cause severe yield losses in many crop plants and are a serious threat to food production in China. However, the reports focused on identification of species abundance and distribution of cyst nematodes on main crops in China are fewer. During 2012-2014, nine populations of cyst nematodes collected from various locations in major crop cultivation areas of China were identified as four species (Heterodera glycines, H. avenae, H. filipjevi, H. elachista) based on morphology and molecular analysis. H. filipjevi and H. elachista were first discovered in Anhui and Jiangxi Provinces, respectively. In addition, a PCR-ITS-RFLP method was applied to distinguish all the studied populations, which revealed molecular characteristics of cyst nematode species on major field crops in China. The present study broadens the knowledge regarding distributions and molecular features of vital Heterodera species and populations, and will also provide useful information for early protection of cystnematodes in China. [ABSTRACT FROM AUTHOR]

Published
2018

5. Expression of TGF-beta signaling proteins in normal placenta and gestational trophoblastic disease

Author

Y H, Xuan, Y L, Choi, Y K, Shin, G H, Ahn, K H, Kim, W J, Kim, H C, Lee, and S H, Kim

Subjects
Adult, Placenta, Receptor, Transforming Growth Factor-beta Type I, Receptor, Transforming Growth Factor-beta Type II, Gestational Age, Smad Proteins, Hydatidiform Mole, Protein Serine-Threonine Kinases, Immunoenzyme Techniques, Transforming Growth Factor beta1, Transforming Growth Factor beta2, Pregnancy, Tissue Array Analysis, Uterine Neoplasms, Biomarkers, Tumor, Humans, Female, Choriocarcinoma, Activin Receptors, Type I, Receptors, Transforming Growth Factor beta
Abstract

The transforming growth factor beta (TGF-beta) is a vital regulator of placental development and functions. TGF-beta exerts several modulatory effects on trophoblast cells, such as inhibition of proliferation and invasiveness, and stimulation of differentiation by inducing multinucleated cell formation. In this study, we determine the expression patterns of TGF-beta signaling molecules in normal trophoblast, various hydatidiform mole types and choriocarcinoma. A total of 132 cases, including 51 normal placenta (20 first trimester, 11 second trimester, and 20 third trimester) and 81 gestational trophoblastic diseases (17 choriocarcinoma, and 64 hydatidiform moles: 39 complete, 6 partial, and 19 invasive) were immunohistochemically analyzed with anti-TGF beta1/2, TGF-beta receptor type I (TbetaRI), TbetaRII, Smad 2/3, and Smad 4 antibodies on paraffin blocks. In the case of normal placenta, maximal levels of all TGF-beta signaling molecules were observed in villous trophoblast in the first trimester, which decreased with gestational age. Expression of all the TGF-beta signaling proteins except Smad2/3, was significantly enhanced in various moles, relative to normal trophoblast. Moreover, TGF-beta signaling molecules were significantly downregulated in choriocarcinoma, compared to moles. In particular, TbetaRI and Smad2/3 levels were lower in choriocarcinoma than normal villous trophoblast (TbetaRI: p0.025, Smad2/3: p0.001). In conclusion, the TGF-beta signaling pathway plays an important role in the pathogenesis and progression of gestational trophoblastic disease, and may thus be employed as a potential therapeutic target and a diagnostic biomarker.

Published
2006

6. An immunohistochemical study of the expression of cell-cycle-regulated proteins p53, cyclin D1, RB, p27, Ki67 and MSH2 in gallbladder carcinoma and its precursor lesions

Author

Y H, Xuan, Y L, Choi, Y K, Shin, M C, Kook, S W, Chae, S M, Park, H B, Chae, and S H, Kim

Subjects
Male, Carcinoma, Cell Cycle Proteins, Immunohistochemistry, Retinoblastoma Protein, DNA-Binding Proteins, Ki-67 Antigen, MutS Homolog 2 Protein, Proliferating Cell Nuclear Antigen, Proto-Oncogene Proteins, Humans, Cyclin D1, Female, Gallbladder Neoplasms, Tumor Suppressor Protein p53, Aged
Abstract

Gallbladder carcinomas are rare but highly lethal neoplasms. We examined the expression of five cell-cycle-related molecules (p53, RB, cyclin D1, p27, Ki-67), and MSH2, in 46 carcinomas, 14 adenomas, 15 low-grade dysplasias, 9 intestinal metaplasias and 20 normal gallbladder epithelia. The expression of these molecules was altered in gallbladder carcinomas and adenomas. In gallbladder carcinomas we observed increased expression of p53, cyclin D1, Ki-67, and MSH2 together with decreased expression of RB and p27 protein. Aberrant expression of cyclin D1 and reduced expression of RB were noted in adenomas, and expression of cyclin D1 was elevated in low-grade dysplasias. However, there was no change in the levels of these cell-cycle molecules in metaplasia. Expression of p53, p27, Ki-67, and MSH2 was correlated with clinical stage (P0.05) and there was also a correlation between the expression of Ki-67 and MSH-2 and patient age (P0.05). These results suggest that altered expression of cell-cycle molecules p53, cyclin D1, RB, p27, and of MSH-2 is involved in the progression of gallbladder carcinomas.

Published
2004

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