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41.
Zhu Y Nam J Humara JM Mysore KS Lee LY Cao H Valentine L Li J Kaiser AD Kopecky AL Hwang HH Bhattacharjee S Rao PK Tzfira T Rajagopal J Yi H Veena Yadav BS Crane YM Lin K Larcher Y Gelvin MJ Knue M Ramos C Zhao X Davis SJ Kim SI Ranjith-Kumar CT Choi YJ Hallan VK Chattopadhyay S Sui X Ziemienowicz A Matthysse AG Citovsky V Hohn B Gelvin SB 《Plant physiology》2003,132(2):494-505
Limited knowledge currently exists regarding the roles of plant genes and proteins in the Agrobacterium tumefaciens-mediated transformation process. To understand the host contribution to transformation, we carried out root-based transformation assays to identify Arabidopsis mutants that are resistant to Agrobacterium transformation (rat mutants). To date, we have identified 126 rat mutants by screening libraries of T-DNA insertion mutants and by using various “reverse genetic” approaches. These mutants disrupt expression of genes of numerous categories, including chromatin structural and remodeling genes, and genes encoding proteins implicated in nuclear targeting, cell wall structure and metabolism, cytoskeleton structure and function, and signal transduction. Here, we present an update on the identification and characterization of these rat mutants. 相似文献
42.
Effect of ulcerative colitis treatment on transforming growth factor beta(1) in plasma and rectal mucosa 总被引:2,自引:0,他引:2
The aim of this study was to evaluate the effect of active ulcerative colitis (UC) treatment on transforming growth factor beta(1) (TGF-beta(1)) concentration in plasma and rectal mucosa measured in 28 patients. The highest plasma values were observed in patients with the severe course of the disease (74.2+/-14.0 ng/ml), and they were significantly higher than in the group with mild one (43.7+/-5.6 ng/ml). Mean TGF-beta(1) measured in mucosal samples from patients with severe UC (563+/-146 pg/mg protein) doubled values from patients with mild UC (286+/-65 pg/mg protein). Plasma and mucosal TGF-beta(1) correlated significantly with disease activity index (DAI) and clinical activity index (CAI). Plasma TGF-beta(1) correlated additionally with scored endoscopic degree of mucosal injury. Treatment caused significant decrease of plasma and mucosal TGF-beta(1) concentrations. Patients who responded completely had higher baseline plasma and mucosal TGF-beta(1) that decreased significantly after the treatment. These results show that plasma and mucosal concentrations of transforming growth factor beta(1) are strongly associated with ulcerative colitis activity, and successful treatment of the disease results with decrease of their levels. More effective response to the treatment can be achieved in patients with higher baseline concentrations of TGF-beta(1). 相似文献
43.
We characterized the Arabidopsis orthologue of the human nuclear import receptor transportin1 (TRN1). Like the human receptor, Arabidopsis TRN1 recognizes nuclear import signals on proteins that are different from the classical basic nuclear localization signals. The M9 domain of human heterogeneous nuclear ribonucleoprotein A1 (hnRNP A1) is the prototype of such signals. We show that AtTRN1 binds to similar domains in hnRNP-like proteins from plants. AtTRN1 also interacts with human hnRNP A1 and with yeast Nab2p, two classical import cargo proteins of transportin in these organisms. Like all nuclear transport receptors of the importin-beta family, AtTRN1 binds to the regulatory GTPase Ran from Arabidopsis. We demonstrated that the amino terminus of AtTRN1 is necessary for this interaction. Recombinant AtTRN1 conferred nuclear import of fluorescently labelled BSA-M9 peptide conjugates in permeabilized HeLa cells, functionally replacing human TRN1 in these in vitro nuclear import assays. We identified three plant substrate proteins that interact with AtTRN1 and contain M9-like domains: a novel Arabidopsis hnRNP that shows high similarity to human hnRNP A1 and two small RNA-binding proteins from Arabidopsis, AtGRP7 and AtGRP8. Nuclear import activity of the M9-like domains of these plant proteins was demonstrated in vivo by their ability to confer partial nuclear re-localisation of a GFP fusion protein containing a nuclear export signal. In addition, fluorescently labelled AtGRP7 was specifically imported into nuclei of permeabilized HeLa cells by Arabidopsis AtTRN1 and human TRN1. These results suggest that the transportin-mediated nuclear import pathway is highly conserved between man, yeast and plants. 相似文献
44.
Somiari RI Sullivan A Russell S Somiari S Hu H Jordan R George A Katenhusen R Buchowiecka A Arciero C Brzeski H Hooke J Shriver C 《Proteomics》2003,3(10):1863-1873
Large-scale proteomics will play a critical role in the rapid display, identification and validation of new protein targets, and elucidation of the underlying molecular events that are associated with disease development, progression and severity. However, because the proteome of most organisms are significantly more complex than the genome, the comprehensive analysis of protein expression changes will require an analytical effort beyond the capacity of standard laboratory equipment. We describe the first high-throughput proteomic analysis of human breast infiltrating ductal carcinoma (IDCA) using OCT (optimal cutting temperature) embedded biopsies, two-dimensional difference gel electrophoresis (2-D DIGE) technology and a fully automated spot handling workstation. Total proteins from four breast IDCAs (Stage I, IIA, IIB and IIIA) were individually compared to protein from non-neoplastic tissue obtained from a female donor with no personal or family history of breast cancer. We detected differences in protein abundance that ranged from 14.8% in stage I IDCA versus normal, to 30.6% in stage IIB IDCA versus normal. A total of 524 proteins that showed > or = three-fold difference in abundance between IDCA and normal tissue were picked, processed and identified by mass spectrometry. Out of the proteins picked, approximately 80% were unambiguously assigned identities by matrix-assisted laser desorbtion/ionization-time of flight mass spectrometry or liquid chromatography-tandem mass spectrometry in the first pass. Bioinformatics tools were also used to mine databases to determine if the identified proteins are involved in important pathways and/or interact with other proteins. Gelsolin, vinculin, lumican, alpha-1-antitrypsin, heat shock protein-60, cytokeratin-18, transferrin, enolase-1 and beta-actin, showed differential abundance between IDCA and normal tissue, but the trend was not consistent in all samples. Out of the proteins with database hits, only heat shock protein-70 (more abundant) and peroxiredoxin-2 (less abundant) displayed the same trend in all the IDCAs examined. This preliminary study demonstrates quantitative and qualitative differences in protein abundance between breast IDCAs and reveals 2-D DIGE portraits that may be a reflection of the histological and pathological status of breast IDCA. 相似文献
45.
Alicja Stach 《Aerobiologia》2000,16(1):63-68
The airborne pollen concentration of the four mostfrequent and most allergenic taxa in Poland; Alnus, Betula, Poaceae, and Artemisia atPozna in the years 1995–1996 has been analyzed,using a Hirst-type volumetric spore trap. Theappearance of the earliest pollen producing taxa wasobserved as early as January and February, which isrelevant information for people subject to allergiesin the Pozna region, where Spring usually beginsin March. The periods of high and very high pollenconcentration of individual taxa have been comparedfor the two years. 相似文献
46.
Molecular Mechanism of Heat Shock-Provoked Disassembly of the Coliphage λ Replication Complex 下载免费PDF全文
Alicja Wgrzyn Anna Herman-Antosiewicz Karol Taylor Grzegorz Wgrzyn 《Journal of bacteriology》1998,180(9):2475-2483
We have found previously that, in contrast to the free O initiator protein of λ phage or plasmid rapidly degraded by the Escherichia coli ClpP/ClpX protease, the λO present in the replication complex (RC) is protected from proteolysis. However, in cells growing in a complete medium, a temperature shift from 30 to 43°C resulted in the decay of the λO fraction, which indicated disassembly of RC. This process occurred due to heat shock induction of the groE operon, coding for molecular chaperones of the Hsp60 system. Here we demonstrate that an increase in the cellular concentration of GroEL and GroES proteins is not in itself sufficient to cause RC disassembly. Another requirement is a DNA gyrase-mediated negative resupercoiling of λ plasmid DNA, which counteracts DNA relaxation and starts to dominate 10 min after the temperature upshift. We presume that RC dissociates from λ DNA during the negative resupercoiling, becoming susceptible to the subsequent action of GroEL/S and ClpP/ClpX proteins. In contrast to λcro+, in λcro− plasmid-harboring cells, the RC reveals heat shock resistance. After temperature upshift of the λcrots plasmid-harboring cells, a Cro repressor-independent control of λ DNA replication and heat shock resistance of RC are established before the period of DNA gyrase-mediated negative supercoiling. We suggest that the tight binding of RC to λ DNA is due to interaction of RC with other DNA-bound proteins, and is related to the molecular basis of the λcro− plasmid replication control. 相似文献
47.
Marzena Rams-Baron Mateusz Dulski Anna Mrozek-Wilczkiewicz Mateusz Korzec Wioleta Cieslik Ewelina Spaczyńska Piotr Bartczak Alicja Ratuszna Jaroslaw Polanski Robert Musiol 《PloS one》2015,10(6)
New styrylquinoline derivatives with their photophysical constants are described. The synthesis was achieved via Sonogashira coupling using the newly developed heterogeneous nano-Pd/Cu catalyst system, which provides an efficient synthesis of high purity products. The compounds were tested in preliminary fluorescent microscopy studies to in order to identify their preferable cellular localization, which appeared to be in the lipid cellular organelles. The spectroscopic properties of the compounds were measured and theoretical TD-DFT calculations were performed. A biological analysis of the quinolines that were tested consisted of cytotoxicity assays against normal human fibroblasts and colon adenocarcinoma cells. All of the compounds that were studied appeared to be safe and indifferent to cells in a high concentration range. The presented results suggest that the quinoline compounds that were investigated in this study may be valuable structures for development as fluorescent dyes that could have biological applications. 相似文献
48.
Barbara Alicja Jereczek-Fossa Sara Ronchi Roberto Orecchia 《Reports of Practical Oncology and Radiotherapy》2015,20(6):472-483
ObjectivesTo review the available data about stereotactic body-radiotherapy (SBRT) for oligometastatic lymph node cancer recurrence.MethodsThe inclusion criteria for this study were as follows: Medline search for the (1) English language (2) full paper (abstracts were excluded) on (3) adult oligometastatic solid cancer recurrence limited to lymph node that underwent SBRT (4) outcome data available and (5) published up to the 30th April 2014.Results38 papers fulfilling the inclusion criteria have been found: 7 review articles and 31 patient series (20 and 11 retrospective and prospective studies, respectively) including between 1 and 69 patients (636 lymph nodes). Twelve articles reported only lymph node SBRT while in 19 – all types of SBRT including lymph node SBRT were presented. Two-year local control, 4-year progression free survival and overall survival was of up to 100%, 30% and 50%, respectively. The progression was mainly out-field (10–30% of patients had a recurrence in another lymph node/nodes). The toxicity was low with mainly mild acute events and single grade 3–4 late events. When compared to SBRT for any oligometastatic cancer, SBRT for lymph node recurrence carried better prognosis and showed lower toxicity.ConclusionsSBRT is a feasible approach for oligometastatic lymph node recurrence, offering excellent in-field tumor control with low toxicity profile. The potential abscopal effect has been hypothesized as a basis of these findings. Future studies are warranted to identify the patients that benefit most from this treatment. The optimal combination with systemic treatment should also be defined. 相似文献
49.
50.
Alicja. J. Copik Aleksander Baldys Khanh Nguyen Sunil Sahdeo Hoangdung Ho Alan Kosaka Paul J. Dietrich Bill Fitch John R. Raymond Anthony P. D. W. Ford Donald Button Marcos E. Milla 《PloS one》2015,10(1)
The α1A-AR is thought to couple predominantly to the Gαq/PLC pathway and lead to phosphoinositide hydrolysis and calcium mobilization, although certain agonists acting at this receptor have been reported to trigger activation of arachidonic acid formation and MAPK pathways. For several G protein-coupled receptors (GPCRs) agonists can manifest a bias for activation of particular effector signaling output, i.e. not all agonists of a given GPCR generate responses through utilization of the same signaling cascade(s). Previous work with Gαq coupling-defective variants of α1A-AR, as well as a combination of Ca2+ channel blockers, uncovered cross-talk between α1A-AR and β2-AR that leads to potentiation of a Gαq-independent signaling cascade in response to α1A-AR activation. We hypothesized that molecules exist that act as biased agonists to selectively activate this pathway. In this report, isoproterenol (Iso), typically viewed as β-AR-selective agonist, was examined with respect to activation of α1A-AR. α1A-AR selective antagonists were used to specifically block Iso evoked signaling in different cellular backgrounds and confirm its action at α1A-AR. Iso induced signaling at α1A-AR was further interrogated by probing steps along the Gαq /PLC, Gαs and MAPK/ERK pathways. In HEK-293/EBNA cells transiently transduced with α1A-AR, and CHO_α1A-AR stable cells, Iso evoked low potency ERK activity as well as Ca2+ mobilization that could be blocked by α1A-AR selective antagonists. The kinetics of Iso induced Ca2+ transients differed from typical Gαq- mediated Ca2+ mobilization, lacking both the fast IP3R mediated response and the sustained phase of Ca2+ re-entry. Moreover, no inositol phosphate (IP) accumulation could be detected in either cell line after stimulation with Iso, but activation was accompanied by receptor internalization. Data are presented that indicate that Iso represents a novel type of α1A-AR partial agonist with signaling bias toward MAPK/ERK signaling cascade that is likely independent of coupling to Gαq. 相似文献