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1.
Identification of different protein functions facilitates a mechanistic understanding of Japanese encephalitis virus (JEV) infection and opens novel means for drug development. Support vector machines (SVM), useful
for predicting the functional class of distantly related proteins, is employed to ascribe a possible functional class to Japanese encephalitis virus protein. Our study from SVMProt and available JE virus sequences
suggests that structural and nonstructural proteins of JEV genome possibly belong to diverse protein functions, are expected to occur in the life cycle of JE virus. Protein functions common to both structural and
non-structural proteins are iron-binding, metal-binding, lipid-binding, copper-binding, transmembrane, outer membrane, channels/Pores - Pore-forming toxins (proteins and peptides) group of proteins. Non-structural
proteins perform functions like actin binding, zinc-binding, calcium-binding, hydrolases, Carbon-Oxygen Lyases, P-type ATPase, proteins belonging to major facilitator family (MFS), secreting main terminal branch (MTB)
family, phosphotransfer-driven group translocators and ATP-binding cassette (ABC) family group of proteins. Whereas structural proteins besides belonging to same structural group of proteins (capsid, structural, envelope),
they also perform functions like nuclear receptor, antibiotic resistance, RNA-binding, DNA-binding, magnesium-binding, isomerase (intra-molecular), oxidoreductase and participate in type II (general) secretory pathway (IISP). 相似文献
2.
Analysis of the distribution and structure of integrated Banana streak virus DNA in a range of Musa cultivars 总被引:2,自引:0,他引:2
Andrew D. W. Geering Neil E. Olszewski Ganesh Dahal John E. Thomas Benham E. L. Lockhart 《Molecular Plant Pathology》2001,2(4):207-213
Banana streak virus strain OL (BSV-OL) commonly infects new Musa hybrids, and this infection is thought to arise de novo from integrated virus sequences present in the nuclear genome of the plant. Integrated DNA (Musa6+8 sequence) containing the whole genome of the virus has previously been cloned from cv. Obino l’Ewai (Musa AAB group), a parent of many of the hybrids. Using a Southern blot hybridization assay, we have examined the distribution and structure of integrated BSV-OL sequences in a range of Musa cultivars. For cv. Obino l’Ewai, almost every restriction fragment hybridizing to BSV-OL was predicted from the Musa6+8 sequence, suggesting that this is the predominant type of BSV-OL integrant in the genome. Furthermore, since only two junction fragments of Musa/BSV sequence were detected, and the Musa6+8 sequence is believed to be integrated as multiple copies in a tandem array, then the internal Musa spacer sequences must be highly conserved. Similarly sized restriction fragments were detected in four BB group cultivars, but not in six AA or AAA group cultivars, suggesting that the BSV-OL sequences are linked to the B-genome of Musa. We also provide evidence that cv. Williams (Musa AAA group) contains a distinct badnavirus integrant that is closely related to the ‘dead’ virus integrant previously characterized from Calcutta 4 (Musa acuminata ssp. burmannicoides). Our results suggest that the virus integrant from cv. Williams is linked to the A-genome, and the complexity of the hybridization patterns suggest multiple sites of integration and/or variation in sequence and structure of the integrants. 相似文献
3.
Anup Mandal Mathews Varkey Sobha Pindaniyil Sobhanan Anjali Kottayil Mani Achamveetil Gopalakrishnan Ganesh Kumaran Arulraj Sethuramalingam Pandiarajan Srinivasan Yohannan Chellema Thampi Samraj 《Biochemical genetics》2014,52(7-8):338-354
The taxonomic ambiguity of the Indian mud crab (genus Scylla de Hann 1833) is still a cause of concern as several papers have been published with misleading identification. This is the first attempt to resolve the taxonomic uncertainty of the mud crab commonly available in Indian coastal waters using molecular genetic markers (ITS-1 and sequencing of COI gene) combined with traditional morphometry. Additionally, we developed a PCR method by which Indian mud crab species can be identified rapidly and effectively. The results clearly indicate that the green morph of the Indian mud crab is Scylla serrata and the brown morph is S. olivacea. The S. serrata commonly mentioned in the literature from India is S. olivacea; the S. tranquebarica noted by many Indian researchers should belong to S. serrata. Caution should be taken when interpreting or implementing the biological, molecular, and aquaculture data in the literature. 相似文献
4.
Roy S Chakravarty D Cortez V De Mukhopadhyay K Bandyopadhyay A Ahn JM Raj GV Tekmal RR Sun L Vadlamudi RK 《Molecular cancer research : MCR》2012,10(1):25-33
Breast cancer metastasis is a major clinical problem. The molecular basis of breast cancer progression to metastasis remains poorly understood. PELP1 is an estrogen receptor (ER) coregulator that has been implicated as a proto-oncogene whose expression is deregulated in metastatic breast tumors and whose expression is retained in ER-negative tumors. We examined the mechanism and significance of PELP1-mediated signaling in ER-negative breast cancer progression using two ER-negative model cells (MDA-MB-231 and 4T1 cells) that stably express PELP1-shRNA. These model cells had reduced PELP1 expression (75% of endogenous levels) and exhibited less propensity to proliferate in growth assays in vitro. PELP1 downregulation substantially affected migration of ER-negative cells in Boyden chamber and invasion assays. Using mechanistic studies, we found that PELP1 modulated expression of several genes involved in the epithelial mesenchymal transition (EMT), including MMPs, SNAIL, TWIST, and ZEB. In addition, PELP1 knockdown reduced the in vivo metastatic potential of ER-negative breast cancer cells and significantly reduced lung metastatic nodules in a xenograft assay. These results implicate PELP1 as having a role in ER-negative breast cancer metastasis, reveal novel mechanism of coregulator regulation of metastasis via promoting cell motility/EMT by modulating expression of genes, and suggest PELP1 may be a potential therapeutic target for metastatic ER-negative breast cancer. 相似文献
5.
Arjun Basnet Pritam Thapa Radha Karki Hoyoung Choi Jae Hun Choi Minho Yun Byeong-Seon Jeong Yurngdong Jahng Younghwa Na Won-Jea Cho Youngjoo Kwon Chong-Soon Lee Eung-Seok Lee 《Bioorganic & medicinal chemistry letters》2010,20(1):42-47
For the development of novel antitumor agents, 2,6-dithienyl-4-furyl pyridine derivatives were prepared and evaluated for their topoisomerase I and II inhibitory activity as well as cytotoxicity against several human cancer cell lines. Among the 21 prepared compounds, compound 24 exhibited strong topoisomerase I inhibitory activity. In addition, a docking study with topoisomerase I and compound 24 was performed. 相似文献
6.
7.
Tamogami S Rakwal R Agrawal GK 《Biochemical and biophysical research communications》2008,376(4):723-727
Methyl jasmonate (MeJA) was identified as an airborne signal involved in mediating interplant defense response communications over a decade ago. However, how MeJA activates plant defense systems and what becomes of the compound after it has done so has, thus far, remained unknown. To investigate this, Achyranthes bidentata plants were exposed to deuterated methyl jasmonate (d2MeJA) followed by absolute quantification of metabolic products of d2MeJA, and emissions of volatile organic compound (VOC) as defensive markers. We found that d2MeJA was metabolized mainly into deuterated jasmonic acid (d2JA) and jasmonoyl isoleucine (d2JA-Ile), and to a much lesser extent, deuterated jasmonoyl leucine (d2JA-Leu). Increases in d2JA-Ile/Leu and also endogenous JA-Ile/Leu were tightly co-related with, and significantly influenced the pattern and amount of, VOC emissions. The amount of accumulated d2JA-IIe was 13.1-fold higher than d2JA-Leu, whereas the amounts of JA-IIe and JA-Leu accumulated were almost identical. This study demonstrates that exogenous MeJA activates defensive systems (such as VOC emissions) in receiver plants by essentially converting itself into JA and JA-IIe and initiating a signal transduction leading to VOC emissions and induction of endogenous JA-IIe and JA-Leu, which in turn cause further amplification of VOC emissions. 相似文献
8.
Kim JA Agrawal GK Rakwal R Han KS Kim KN Yun CH Heu S Park SY Lee YH Jwa NS 《Biochemical and biophysical research communications》2003,300(4):868-876
Mitogen-activated protein kinase (MAPK) cascade(s) is important for plant defense/stress responses. Though MAPKs have been identified and characterized in rice (Oryza sativa L.), a monocot cereal crop research model, the first upstream component of the kinase cascade, namely MAPK kinase kinase (MAPKKK) has not yet been identified. Here we report the cloning of a novel rice gene encoding a MAPKKK, OsEDR1, designated based on its homology with the Arabidopsis MAPKKK, AtEDR1. OsEDR1, a single copy gene in the genome of rice, encodes a predicted protein with molecular mass of 113046.13 and a pI of 9.03. Using our established two-week-old rice seedling in vitro model system, we show that OsEDR1 has a constitutive expression in seedling leaves and is further up-regulated within 15 min upon wounding by cut, treatment with the global signals jasmonic acid (JA), salicylic acid (SA), ethylene (ethephon, ET), abscisic acid, and hydrogen peroxide. In addition, protein phosphatase inhibitors, fungal elicitor chitosan, drought, high salt and sugar, and heavy metals also dramatically induce its expression. Moreover, OsEDR1 expression was altered by co-application of JA, SA, and ET, and required de novo synthesized protein factor(s) in its transient regulation. Furthermore, using an in vivo system we also show that OsEDR1 responds to changes in temperature and environmental pollutants-ozone and sulfur dioxide. Finally, OsEDR1 expression varied significantly in vegetative and reproductive tissues. These results suggest a role for OsEDR1 in defense/stress signalling pathways and development. 相似文献
9.
10.
Clubbed [1,2,3] triazoles by fluorine benzimidazole: a novel approach to H37Rv inhibitors as a potential treatment for tuberculosis 总被引:1,自引:0,他引:1
Gill C Jadhav G Shaikh M Kale R Ghawalkar A Nagargoje D Shiradkar M 《Bioorganic & medicinal chemistry letters》2008,18(23):6244-6247
A Novel Clubbed [1,2,3] triazoles with fluorine benzimidazole series of H37Rv strain inhibitors, potentially useful for the treatment of tuberculosis is disclosed on the basis of promising results of preliminary antimicrobial study. Evaluation of the SAR of substitution within these series has followed the identification of a range of compounds. Some of the derivatives are under further evaluation showing better considerable activity compared to rifampin. 相似文献