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31.
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
32.
Lukáš Kubala Hana Kolářová Jan Víteček Silvie Kremserová Anna Klinke Denise Lau Anna L.P. Chapman Stephan Baldus Jason P. Eiserich 《Biochimica et Biophysica Acta (BBA)/General Subjects》2013
Background
Myeloperoxidase (MPO) is an abundant hemoprotein expressed by neutrophil granulocytes that is recognized to play an important role in the development of vascular diseases. Upon degranulation from circulating neutrophil granulocytes, MPO binds to the surface of endothelial cells in an electrostatic-dependent manner and undergoes transcytotic migration to the underlying extracellular matrix (ECM). However, the mechanisms governing the binding of MPO to subendothelial ECM proteins, and whether this binding modulates its enzymatic functions are not well understood.Methods
We investigated MPO binding to ECM derived from aortic endothelial cells, aortic smooth muscle cells, and fibroblasts, and to purified ECM proteins, and the modulation of these associations by glycosaminoglycans. The oxidizing and chlorinating potential of MPO upon binding to ECM proteins was tested.Results
MPO binds to the ECM proteins collagen IV and fibronectin, and this association is enhanced by the pre-incubation of these proteins with glycosaminoglycans. Correspondingly, an excess of glycosaminoglycans in solution during incubation inhibits the binding of MPO to collagen IV and fibronectin. These observations were confirmed with cell-derived ECM. The oxidizing and chlorinating potential of MPO was preserved upon binding to collagen IV and fibronectin; even the potentiation of MPO activity in the presence of collagen IV and fibronectin was observed.Conclusions
Collectively, the data reveal that MPO binds to ECM proteins on the basis of electrostatic interactions, and MPO chlorinating and oxidizing activity is potentiated upon association with these proteins.General significance
Our findings provide new insights into the molecular mechanisms underlying the interaction of MPO with ECM proteins. 相似文献33.
Genetic engineering of cytokinin metabolism: Prospective way to improve agricultural traits of crop plants 总被引:1,自引:0,他引:1
David Zalabák Hana Pospíšilová Mária Šmehilová Katarína Mrízová Ivo Frébort Petr Galuszka 《Biotechnology advances》2013
Cytokinins (CKs) are ubiquitous phytohormones that participate in development, morphogenesis and many physiological processes throughout plant kingdom. In higher plants, mutants and transgenic cells and tissues with altered activity of CK metabolic enzymes or perception machinery, have highlighted their crucial involvement in different agriculturally important traits, such as productivity, increased tolerance to various stresses and overall plant morphology. Furthermore, recent precise metabolomic analyses have elucidated the specific occurrence and distinct functions of different CK types in various plant species. Thus, smooth manipulation of active CK levels in a spatial and temporal way could be a very potent tool for plant biotechnology in the future. This review summarises recent advances in cytokinin research ranging from transgenic alteration of CK biosynthetic, degradation and glucosylation activities and CK perception to detailed elucidation of molecular processes, in which CKs work as a trigger in model plants. The first attempts to improve the quality of crop plants, focused on cereals are discussed, together with proposed mechanism of action of the responses involved. 相似文献
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36.
Jiří Kopáček Bernard J. Cosby Christopher D. Evans Jakub Hruška Filip Moldan Filip Oulehle Hana Šantrůčková Karolina Tahovská Richard F. Wright 《Biogeochemistry》2013,115(1-3):33-51
Elevated and chronic nitrogen (N) deposition to N-limited terrestrial ecosystems can lead to ‘N saturation’, with resultant ecosystem damage and leaching of nitrate (NO3 ?) to surface waters. Present-day N deposition, however, is often a poor predictor of NO3 ? leaching, and the pathway of the ecosystem transition from N-limited to N-saturated remains incompletely understood. The dynamics of N cycling are intimately linked to the associated carbon (C) and sulphur (S) cycles. We hypothesize that N saturation is associated with shifts in the microbial community, manifest by a decrease in the fungi-to-bacteria ratio and a transition from N to C limitation. Three mechanisms could lead to lower amount of bioavailable dissolved organic C (DOC) for the microbial community and to C limitation of N-rich systems: (1) Increased abundance of N for plant uptake, causing lower C allocation to plant roots; (2) chemical suppression of DOC solubility by soil acidification; and (3) enhanced mineralisation of DOC due to increased abundance of electron acceptors in the form of ${{\text{SO}}_{ 4}}^{ 2-}$ SO 4 2 ? and NO3 ? in anoxic soil micro-sites. Here we consider each of these mechanisms, the extent to which their hypothesised impacts are consistent with observations from intensively-monitored sites, and the potential to improve biogeochemical models by incorporating mechanistic links to the C and S cycles. 相似文献
37.
Veronika Slancarova Jana Zdanska Bohuslav Janousek Martina Talianova Christian Zschach Jitka Zluvova Jiri Siroky Viera Kovacova Hana Blavet Jiri Danihelka Bengt Oxelman Alex Widmer Boris Vyskot 《Evolution; international journal of organic evolution》2013,67(12):3669-3677
The plant genus Silene has become a model for evolutionary studies of sex chromosomes and sex‐determining mechanisms. A recent study performed in Silene colpophylla showed that dioecy and the sex chromosomes in this species evolved independently from those in Silene latifolia, the most widely studied dioecious Silene species. The results of this study show that the sex‐determining system in Silene otites, a species related to S. colpophylla, is based on female heterogamety, a sex determination system that is unique among the Silene species studied to date. Our phylogenetic data support the placing of S. otites and S. colpophylla in the subsection Otites and the analysis of ancestral states suggests that the most recent common ancestor of S. otites and S. colpophylla was most probably dioecious. These observations imply that a switch from XX/XY sex determination to a ZZ/ZW system (or vice versa) occurred in the subsection Otites. This is the first report of two different types of heterogamety within one plant genus of this mostly nondioecious plant family. 相似文献
38.
Anmar Khadra Melanija Tomić Zonghe Yan Hana Zemkova Arthur Sherman Stanko S. Stojilkovic 《Biophysical journal》2013
The ATP-gated P2X7 receptor channel (P2X7R) operates as a cytolytic and apoptotic receptor but also controls sustained cellular responses, including cell growth and proliferation. However, it has not been clarified how the same receptor mediates such opposing effects. To address this question, we have combined electrophysiological, imaging, and mathematical studies using wild-type and mutant rat P2X7Rs. Activation of naïve (not previously stimulated) receptors by low agonist concentrations caused monophasic slow desensitizing currents and internalization of receptors without other changes in the cellular morphology, much like other P2XRs. In contrast, saturating agonist concentrations induced high-amplitude biphasic currents, reflecting pore dilation and causing rapid cell swelling and lysis. The existence of these two signaling patterns was accounted for using a revised Markov-state model that included, in addition to naïve and sensitized states, desensitized states. Occupancy of one or two ATP-binding sites of naïve receptors favored a slow transition to desensitized states, whereas occupancy of the third binding site favored a transition to sensitized/dilated states. Consistent with model predictions, nondilating P2X7R mutants always generated desensitizing currents. These results suggest that the level of saturation of the ligand binding sites determines the nature of the P2X7R gating and cellular actions. 相似文献
39.
Silvia Petrezselyova Olga Kinclova-Zimmermannova Hana Sychrova 《生物化学与生物物理学报:生物膜》2013,1828(2):623-631
Cation–Cl? cotransporters (CCCs) are integral membrane proteins which catalyze the coordinated symport of Cl? with Na+ and/or K+ ions in plant and mammalian cells. Here we describe the first Saccharomyces cerevisiae CCC protein, encoded by the YBR235w open reading frame. Subcellular localization studies showed that this yeast CCC is targeted to the vacuolar membrane. Deletion of the YBR235w gene in a salt-sensitive strain (lacking the plasma-membrane cation exporters) resulted in an increased sensitivity to high KCl, altered vacuolar morphology control and decreased survival upon hyperosmotic shock. In addition, deletion of the YBR235w gene in a mutant strain deficient in K+ uptake produced a significant growth advantage over the parental strain under K+-limiting conditions, and a hypersensitivity to the exogenous K+/H+ exchanger nigericin. These results strongly suggest that we have identified a novel yeast vacuolar ion transporter mediating a K+–Cl? cotransport and playing a role in vacuolar osmoregulation. Considering its identified function, we propose to refer to the yeast YBR235w gene as VHC1 (vacuolar protein homologous to CCC family 1). 相似文献
40.
Helena Ambrozova Vilma Maresova Martin Fajt Petr Pavlicek Hana Rohacova Ivana Machova Petr Petras 《Folia microbiologica》2013,58(3):225-228
Panton–Valentine leukocidin-producing strains of Staphylococcus aureus can cause severe skin and soft tissue infections and necrotizing pneumonia with a high mortality rate. This is a report on the first case of fatal pneumonia with mediastinitis in an infant in the Czech Republic. The causative agent was a methicillin-susceptible S. aureus strain with pronounced production of the PVL toxin and hyperproduction of enterotoxin A. 相似文献