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91.
Dario A. Breitel Louise Chappell-Maor Sagit Meir Irina Panizel Clara Pons Puig Yanwei Hao Tamar Yifhar Hagai Yasuor Mohamed Zouine Mondher Bouzayen Antonio Granell Richart Ilana Rogachev Asaph Aharoni 《PLoS genetics》2016,12(3)
The involvement of ethylene in fruit ripening is well documented, though knowledge regarding the crosstalk between ethylene and other hormones in ripening is lacking. We discovered that AUXIN RESPONSE FACTOR 2A (ARF2A), a recognized auxin signaling component, functions in the control of ripening. ARF2A expression is ripening regulated and reduced in the rin, nor and nr ripening mutants. It is also responsive to exogenous application of ethylene, auxin and abscisic acid (ABA). Over-expressing ARF2A in tomato resulted in blotchy ripening in which certain fruit regions turn red and possess accelerated ripening. ARF2A over-expressing fruit displayed early ethylene emission and ethylene signaling inhibition delayed their ripening phenotype, suggesting ethylene dependency. Both green and red fruit regions showed the induction of ethylene signaling components and master regulators of ripening. Comprehensive hormone profiling revealed that altered ARF2A expression in fruit significantly modified abscisates, cytokinins and salicylic acid while gibberellic acid and auxin metabolites were unaffected. Silencing of ARF2A further validated these observations as reducing ARF2A expression let to retarded fruit ripening, parthenocarpy and a disturbed hormonal profile. Finally, we show that ARF2A both homodimerizes and interacts with the ABA STRESS RIPENING (ASR1) protein, suggesting that ASR1 might be linking ABA and ethylene-dependent ripening. These results revealed that ARF2A interconnects signals of ethylene and additional hormones to co-ordinate the capacity of fruit tissue to initiate the complex ripening process. 相似文献
92.
93.
Ekaterina Spiridonova Irina Nesterkina Veronika Gurina Vadim Nurminsky Lyudmila Donskaya 《International journal of phytoremediation》2019,21(10):980-984
AbstractThe article dwells upon identifying the effect of cadmium on the roots of beetroot. The exposure effects of various concentrations of cadmium were studied at different levels of the plant organization (tissue pieces, organelles, membrane vesicles). The effect was noted only at a concentration of 100?μm. The negative effect of cadmium on the roots tissues of beetroot appeared with an increase in permeability and a decrease in the stability of cell membranes due to a change in the composition of fatty acids of membrane lipids and an increase in oxidation processes. The effect of cadmium in model experiments on the activity of the proton pumps of the vacuolar membrane has been evaluated. The pumps provide for the transport of heavy metals into the vacuole, which is one of the effective mechanisms for phytoremediation. The influence of cadmium in model experiments on the activity of the proton pump of a vacuolar membrane was evaluated. Under the influence of cadmium, a decrease in the activity of V-ATPase was observed, while the activity of V-PPase did not change. The results obtained complement our understanding of the damaging effects that occur in plant cells under cadmium stress. 相似文献
94.
Natalia Poplavskaya Anna Bannikova Karsten Neumann Marina Pavlenko Irina Kartavtseva Yuriy Bazhenov Pavel Bogomolov Alexey Abramov Alexey Surov Vladimir Lebedev 《Journal of Zoological Systematics and Evolutionary Research》2019,57(3):679-694
Striped hamsters (Cricetulus barabensis sensu lato) represent a complex of chromosomally distinct allopatric lineages/taxa of either species or subspecies rank. They are widely distributed across the steppes of eastern and central Palearctic. Phylogenetic analysis of cytochrome b gene sequences based on 496 specimens from 112 localities revealed five well‐supported lineages divergent at 2%–4%. Two of them correspond to “griseus” (2n = 22) and “pseudogriseus” (2n = 24) karyomorphs and are placed as sister taxa. The “barabensis” (2n = 20) karyomorph is represented by three other branches and appears non‐monophyletic. All mtDNA lineages are distributed allopatrically or parapatrically; no indications of gene flow between populations of different chromosomal races were found. The results of the molecular clock analysis suggest that the main lineages diverged in the late Middle Pleistocene. The inferred evolutionary scenario implies that the common ancestor of the recent lineages belonged to the 2n = 20 karyomorph and originated in the eastern part of the contemporary range. 相似文献
95.
96.
Anna Filippova Irina Lyapina Ilya Kirov Victor Zgoda Alexey Belogurov Anna Kudriaeva Vadim Ivanov Igor Fesenko 《Journal of peptide science》2019,25(2)
Plant secretome comprises dozens of secreted proteins. However, little is known about the composition of the whole secreted peptide pools and the proteases responsible for the generation of the peptide pools. The majority of studies focus on target detection and characterization of specific plant peptide hormones. In this study, we performed a comprehensive analysis of the whole extracellular peptidome, using moss Physcomitrella patens as a model. Hundreds of modified and unmodified endogenous peptides that originated from functional and nonfunctional protein precursors were identified. The plant proteases responsible for shaping the pool of endogenous peptides were predicted. Salicylic acid (SA) influenced peptide production in the secretome. The proteasome activity was altered upon SA treatment, thereby influencing the composition of the peptide pools. These results shed more light on the role of proteases and posttranslational modification in the “active management” of the extracellular peptide pool in response to stress conditions. It also identifies a list of potential peptide hormones in the moss secretome for further analysis. 相似文献
97.
Zishu Liu Nicolas Cichocki Thomas Hübschmann Christine Süring Irina Dana Ofiţeru William T. Sloan Volker Grimm Susann Müller 《Environmental microbiology》2019,21(1):164-181
In completely insular microbial communities, evolution of community structure cannot be shaped by the immigration of new members. In addition, when those communities are run in steady state, the influence of environmental factors on their assembly is reduced. Therefore, one would expect similar community structures under steady-state conditions. Yet, in parallel setups, variability does occur. To reveal ecological mechanisms behind this phenomenon, five parallel reactors were studied at the single-cell level for about 100 generations and community structure variations were quantified by ecological measures. Whether community variability can be controlled was tested by implementing soft temperature stressors as potential synchronizers. The low slope of the lognormal rank-order abundance curves indicated a predominance of neutral mechanisms, i.e., where species identity plays no role. Variations in abundance ranks of subcommunities and increase in inter-community pairwise β-diversity over time support this. Niche differentiation was also observed, as indicated by steeper geometric-like rank-order abundance curves and increased numbers of correlations between abiotic and biotic parameters during initial adaptation and after disturbances. Still, neutral forces dominated community assembly. Our findings suggest that complex microbial communities in insular steady-state environments can be difficult to synchronize and maintained in their original or desired structure, as they are non-equilibrium systems. 相似文献
98.
99.
Kevin Ni Amar Gill Danting Cao Kengo Koike Kelly S. Schweitzer Stavros Garantziotis Irina Petrache 《Biochemistry and Biophysics Reports》2019
During inflammation, the covalent linking of the ubiquitous extracellular polysaccharide hyaluronan (HA) with the heavy chains (HC) of the serum protein inter alpha inhibitor (IαI) is exclusively mediated by the enzyme tumor necrosis factor α (TNFα)-stimulated-gene-6 (TSG-6). While significant advances have been made regarding how HC-modified HA (HC-HA) is an important regulator of inflammation, it remains unclear why HC-HA plays a critical role in promoting survival in intraperitoneal lipopolysaccharide (LPS)-induced endotoxemia while exerting only a modest role in the outcomes following intratracheal exposure to LPS. To address this gap, the two models of intraperitoneal LPS-induced endotoxic shock and intratracheal LPS-induced acute lung injury were directly compared in TSG-6 knockout mice and littermate controls. HC-HA formation, endogenous TSG-6 activity, and inflammatory markers were assessed in plasma and lung tissue. TSG-6 knockout mice exhibited accelerated mortality during endotoxic shock. While both intraperitoneal and intratracheal LPS induced HC-HA formation in lung parenchyma, only systemically-induced endotoxemia increased plasma TSG-6 levels and intravascular HC-HA formation. Cultured human lung microvascular endothelial cells secreted TSG-6 in response to both TNFα and IL1β stimulation, indicating that, in addition to inflammatory cells, the endothelium may secrete TSG-6 into circulation during systemic inflammation. These data show for the first time that LPS-induced systemic inflammation is uniquely characterized by significant vascular induction of TSG-6 and HC-HA, which may contribute to improved outcomes of endotoxemia. 相似文献
100.
Irina V. Kravchenko Vladimir A. Furalyov Vladimir O. Popov 《Biochemistry and Biophysics Reports》2019
The effects of potassium chloride on the expression of IGF-1 splice forms and myoblast proliferation were investigated. KCl at the concentrations of 7–12 mM stimulated the synthesis of IGF-1 and mechano growth factor (MGF) in murine myoblasts as well as in myotubes both at the mRNA and protein levels. Pan-calcium channel blocker CdCl2 completely abolished stimulation of growth factor expression, whereas blocker of HCN and Nav1.4 channels ZD7288 drastically reduced it. In addition, potassium chloride stimulated myoblast proliferation, while IGF-1 autocrine signaling inhibition partially suppressed these mitogenic effects. 相似文献