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51.
52.
Uma Shankar Sagaram Kaoutar El-Mounadi Garry W. Buchko Howard R. Berg Jagdeep Kaur Raghu S. Pandurangi Thomas J. Smith Dilip M. Shah 《PloS one》2013,8(12)
MtDef4 is a 47-amino acid cysteine-rich evolutionary conserved defensin from a model legume Medicago truncatula. It is an apoplast-localized plant defense protein that inhibits the growth of the ascomycetous fungal pathogen Fusarium graminearum in vitro at micromolar concentrations. Little is known about the mechanisms by which MtDef4 mediates its antifungal activity. In this study, we show that MtDef4 rapidly permeabilizes fungal plasma membrane and is internalized by the fungal cells where it accumulates in the cytoplasm. Furthermore, analysis of the structure of MtDef4 reveals the presence of a positively charged γ-core motif composed of β2 and β3 strands connected by a positively charged RGFRRR loop. Replacement of the RGFRRR sequence with AAAARR or RGFRAA abolishes the ability of MtDef4 to enter fungal cells, suggesting that the RGFRRR loop is a translocation signal required for the internalization of the protein. MtDef4 binds to phosphatidic acid (PA), a precursor for the biosynthesis of membrane phospholipids and a signaling lipid known to recruit cytosolic proteins to membranes. Amino acid substitutions in the RGFRRR sequence which abolish the ability of MtDef4 to enter fungal cells also impair its ability to bind PA. These findings suggest that MtDef4 is a novel antifungal plant defensin capable of entering into fungal cells and affecting intracellular targets and that these processes are mediated by the highly conserved cationic RGFRRR loop via its interaction with PA. 相似文献
53.
Vascular endothelial growth factor (VEGF) is an angiogenic mitogen involved in promoting tumor angiogenesis inside the body. VEGF is a key protein required for progression of tumor from benign to malignant phenotype. In this study, we investigated the binding affinity of a previously selected 26-mer DNA aptamer sequence (SL2-B) against heparin binding domain (HBD) of VEGF165 protein. The SL2-B was first chemically modified by introduction of phosphorothioate linkages (PS-linkages). Subsequently, surface plasmon resonance (SPR) spectroscopy and circular dichroism (CD) were used to determine the binding affinity, specificity and to deduce the conformation of PS-modified SL2-B sequence. Finally, antiproliferative activity of the modified SL2-B sequence on Hep G2 cancer cells was investigated. Our results demonstrate a marked enhancement in the biostability of the SL2-B sequence after PS modification. The modified SL2-B sequence also exhibits enhanced antiproliferative activity against Hep G2 cancer cells in hypoxia conditions. In addition, modified SL2-B sequence inhibits the expression of Jagged-1 protein, which is one of the ligands to VEGF linked delta/jagged-notch signaling pathway. 相似文献
54.
Hong Sung Hyun Singh Sudhir Tripathi Bhumi Nath Mondal Suvendu Lee Sangmin Jung Hyun Suk Cho Chuloh Kaur Shubhpreet Kim Jin-Hong Lee Sungbeom Bai Hyoung-Woo Bae Hyeun-Jong Lee Sang Yeol Lee Seung Sik Chung Byung Yeoup 《Protoplasma》2020,257(3):807-817
Protoplasma - Alkyl hydroperoxide reductase subunit F (AhpF) is a well-known flavoprotein that transfers electrons from pyridine nucleotides to the peroxidase protein AhpC via redox-active... 相似文献
55.
Kaur Parampreet Jindal Suruchi Yadav Bharat Yadav Inderjit Mahato Ajay Sharma Priti Kaur Satinder Gupta O. P. Vrána Jan Šimková Hana Doležel Jaroslav Gill Bikram Singh Meyer Klaus F. X. Khurana J. P. Singh N. K. Chhuneja Parveen Singh Kuldeep 《Molecular biology reports》2020,47(3):1991-2003
Molecular Biology Reports - Diploid A genome wheat species harbor immense genetic variability which has been targeted and proven useful in wheat improvement. Development and deployment of... 相似文献
56.
Kaur Jasmeet Akhatar Javed Goyal Anna Kaur Navneet Kaur Snehdeep Mittal Meenakshi Kumar Nitin Sharma Heena Banga Shashi Banga S. S. 《Molecular biology reports》2020,47(4):2963-2974
Molecular Biology Reports - We investigated phenotypic variations for pod shattering, pod length and number of seeds per pod in large germplasm collections of Brassica juncea (2n?=?36;... 相似文献
57.
The glucagon receptor (GCGR) activated by the peptide hormone glucagon is a seven-transmembrane G protein–coupled receptor (GPCR) that regulates blood glucose levels. Ubiquitination influences trafficking and signaling of many GPCRs, but its characterization for the GCGR is lacking. Using endocytic colocalization and ubiquitination assays, we have identified a correlation between the ubiquitination profile and recycling of the GCGR. Our experiments revealed that GCGRs are constitutively ubiquitinated at the cell surface. Glucagon stimulation not only promoted GCGR endocytic trafficking through Rab5a early endosomes and Rab4a recycling endosomes, but also induced rapid deubiquitination of GCGRs. Inhibiting GCGR internalization or disrupting endocytic trafficking prevented agonist-induced deubiquitination of the GCGR. Furthermore, a Rab4a dominant negative (DN) that blocks trafficking at recycling endosomes enabled GCGR deubiquitination, whereas a Rab5a DN that blocks trafficking at early endosomes eliminated agonist-induced GCGR deubiquitination. By down-regulating candidate deubiquitinases that are either linked with GPCR trafficking or localized on endosomes, we identified signal-transducing adaptor molecule–binding protein (STAMBP) and ubiquitin-specific protease 33 (USP33) as cognate deubiquitinases for the GCGR. Our data suggest that USP33 constitutively deubiquitinates the GCGR, whereas both STAMBP and USP33 deubiquitinate agonist-activated GCGRs at early endosomes. A mutant GCGR with all five intracellular lysines altered to arginines remains deubiquitinated and shows augmented trafficking to Rab4a recycling endosomes compared with the WT, thus affirming the role of deubiquitination in GCGR recycling. We conclude that the GCGRs are rapidly deubiquitinated after agonist-activation to facilitate Rab4a-dependent recycling and that USP33 and STAMBP activities are critical for the endocytic recycling of the GCGR. 相似文献
58.
Talwinder Kaur Deepika Sharma Amarjeet Kaur 《Archives Of Phytopathology And Plant Protection》2013,46(14):1756-1768
The objective of this study was the isolation and screening of actinomycete isolates for antagonistic potential and plant growth promoting activities. A total of 321 isolates were recovered from different plants, their rhizospheric soils and non-rhizospheric soils of Punjab and Himachal Pradesh regions. Out of these, 62 were endophytic, 156 were rhizospheric and 103 were non-rhizospheric isolates. In primary screening (dual culture assay), 83 isolates antagonised one or more test phytopathogenic fungi. From these active isolates, 20 were found to be antagonistic in well diffusion assay (secondary screening) and most of them demonstrated broad spectrum inhibitory activity against five to six test fungi. Studies on plant growth promoting activities revealed that 12 showed abilities to produce indole acetic acid, 10 produced siderophores and 12 showed ammonia production. Phosphate solubilisation was observed in five isolates and four fixed atmospheric N2. In addition, production of hydrolytic enzymes such as chitinase, amylase, cellulase and protease was demonstrated by five, twenty, eleven and eleven isolates, respectively. The results of this study indicate that these isolates may be used as biocontrol and plant growth promoting agents. Morphological and chemotaxonomic studies revealed that all the active isolates belonged to the genus Streptomyces 相似文献
59.
Parthenium hysterophorus L. an exotic, pernicious weed is considered as one of the most troublesome weeds for agricultural sector by virtue of its high ecological amplitude and adaptability. Microbes and their by-products are now proved to be a worthy alternative to toxic chemicals used for weed management. Alternaria macrospora MKPI was isolated from the parthenium leaves infected with leaf blight and found pathogenic to the weed. The herbicidal potential of cell free culture filtrate of A. macrospora MKP1 has been tested against parthenium by employing detached leaf bioassay and seed germination bioassay and a significant damage was exhibited by the cultural filtrate of pathogen to the parthenium leaves and seeds. 相似文献
60.
Ted T. Sakai James M. Riordan Narinder G. Kumar Frederick J. Haberle Gabriel A. Elgavish Jerry D. Glickson 《Journal of biomolecular structure & dynamics》2013,31(3):809-827
Abstract The bleomycins, a group of antitumor antibiotics (Figure 1), cause the degradation of DNA by a process requiring iron(II) and dioxygen (1,2). DNA degradation appears to involve two steps: association of the drug with the nucleic acid and degradation of the DNA. As part of studies directed toward achieving an understanding of how the bleomycins degrade DNA, we have examined various properties of the drug using a variety of chemical and physico- chemical techniques, including NMR and Mössbauer spectroscopy. We have studied both the interaction of the antibiotic with its target (DNA) as well as its association with its metal ion cofactor. This work has been performed on the intact drug and its derivatives as well as on synthetic models of the parent drug. This paper reviews and updates the recent work from this laboratory on the bleomycins. 相似文献