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101.
Involvement of 14-3-3 proteins in the osmotic regulation of H+-ATPase in plant plasma membranes 总被引:2,自引:0,他引:2
Babakov AV Chelysheva VV Klychnikov OI Zorinyanz SE Trofimova MS De Boer AH 《Planta》2000,211(3):446-448
Taking the binding of fusicoccin to plasma membranes as an indicator of complex formation between the 14-3-3 dimer and H+-ATPase, we assessed the effect of osmotic stress on the interaction of these proteins in suspension-cultured cells of sugar
beet (Beta vulgaris L.). An increase in osmolarity of the cell incubation medium, accompanied by a decrease in turgor, was found to activate
the H+ efflux 5-fold. The same increment was observed in the number of high-affinity fusicoccin-binding sites in isolated plasma
membranes; the 14-3-3 content in the membranes increased 2- to 3-fold, while the H+-ATPase activity changed only slightly. The data obtained indicate that osmotic regulation of H+-ATPase in the plant plasma membrane is achieved via modulation of the coupling between H+ transport and ATP hydrolysis, and that such regulation involves 14-3-3 proteins.
Received: 10 February 2000 / Accepted: 31 March 2000 相似文献
102.
103.
Svetlana A. Dambinova Oleg K. Granstrem Alexandre Tourov †Roberto Salluzzo †Filippa Castello Galina A. Izykenova 《Journal of neurochemistry》1998,71(5):2088-2093
Abstract: We have monitored EEG spontaneous spiking activity and analyzed serum from rats with cobalt-induced epilepsy for the presence of autoreactive antibodies to α-amino-3-hydroxy-5-methylisoxazole-4-propionate (AMPA) glutamate receptor subunits. The presence and the level of autoantibodies were assessed using immunoblot and ELISA with synthetic peptide specific to the N-terminus domain of the GluR1 subunit of the AMPA receptor. Rats with cobalt-induced epilepsy exhibited strong GluR1 immunoreactivity at the end of the first week after surgery compared with vehicle-treated rats. We showed that GluR1 autoantibodies in blood serum of rats with cobalt-induced epilepsy preceded the spiking activity maximum in the EEG. Levels of autoantibodies to GluR1 detected in blood of these rats remained elevated when EEG spiking activity was significantly reduced and seizures disappeared. The EEG monitoring of spiking activity showed a correlation with accumulation of GluR1 autoantibodies in blood serum of rats with cobalt-induced epilepsy. 相似文献
104.
Reduced toxicity and broad spectrum resistance to viral and fungal infection in transgenic plants expressing pokeweed antiviral protein II 总被引:3,自引:0,他引:3
Pokeweed antiviral protein II (PAPII), a 30 kDa protein isolated from leaves of Phytolacca americana, inhibits translation by catalytically removing a specific adenine residue from the large rRNA of the 60S subunit of eukaryotic ribosomes. The protein sequence of PAPII shows only 41% identity to PAP and PAP-S, two other antiviral proteins isolated from pokeweed. We isolated a cDNA corresponding to PAPII and introduced it into tobacco plants. PAPII expressed in transgenic tobacco was correctly processed to the mature form as in pokeweed and accumulated to at least 10-fold higher levels than wild-type PAP. We had previously observed a significant decrease in transformation frequency with PAP and recovered only two transgenic lines expressing 1–2 ng per mg protein. In contrast, eight different transgenic lines expressing up to 250 ng/mg PAPII were recovered, indicating that PAPII is less toxic than PAP. Two symptomless transgenic lines expressing PAPII were resistant to tobacco mosaic virus, potato virus X and the fungal pathogen Rhizoctonia solani. The level of viral and fungal resistance observed correlated well with the amount of PAPII protein accumulated. Pathogenesis-related protein PR1 was constitutively expressed in transgenic lines expressing PAPII. Although PR1 was constitutively expressed, no increase in salicylic acid levels was detected, indicating that PAPII may elicit a salicylic acid-independent signal transduction pathway. 相似文献
105.
Vera S. Bogdanova Olga O. Zaytseva Anatoliy V. Mglinets Natalia V. Shatskaya Oleg E. Kosterin Gennadiy V. Vasiliev 《PloS one》2015,10(3)
In crosses of wild and cultivated peas (Pisum sativum L.), nuclear-cytoplasmic incompatibility frequently occurs manifested as decreased pollen fertility, male gametophyte lethality, sporophyte lethality. High-throughput sequencing of plastid genomes of one cultivated and four wild pea accessions differing in cross-compatibility was performed. Candidate genes for involvement in the nuclear-plastid conflict were searched in the reconstructed plastid genomes. In the annotated Medicago truncatula genome, nuclear candidate genes were searched in the portion syntenic to the pea chromosome region known to harbor a locus involved in the conflict. In the plastid genomes, a substantial variability of the accD locus represented by nucleotide substitutions and indels was found to correspond to the pattern of cross-compatibility among the accessions analyzed. Amino acid substitutions in the polypeptides encoded by the alleles of a nuclear locus, designated as Bccp3, with a complementary function to accD, fitted the compatibility pattern. The accD locus in the plastid genome encoding beta subunit of the carboxyltransferase of acetyl-coA carboxylase and the nuclear locus Bccp3 encoding biotin carboxyl carrier protein of the same multi-subunit enzyme were nominated as candidate genes for main contribution to nuclear-cytoplasmic incompatibility in peas. Existence of another nuclear locus involved in the accD-mediated conflict is hypothesized. 相似文献
106.
Nadezda Shershakova Elena Bashkatova Alexander Babakhin Sergey Andreev Alexandra Nikonova Igor Shilovsky Oleg Kamyshnikov Andrey Buzuk Olga Elisyutina Elena Fedenko Musa Khaitov 《PloS one》2015,10(8)
Atopic dermatitis (AD) is a widespread and difficult to treat allergic skin disease and is a tough challenge for healthcare. In this study, we investigated whether allergen-specific immunotherapy (ASIT) with a monomeric allergoid obtained by succinylation of ovalbumin (sOVA) is effective in a mouse model of atopic dermatitis. An experimental model of AD was reproduced by epicutaneous sensitization with ovalbumin (OVA). ASIT was performed with subcutaneous (SC) administration of increasing doses of OVA or sOVA. The levels of anti-OVA antibodies, as well as cytokines, were detected by ELISA. Skin samples from patch areas were taken for histologic examination. ASIT with either OVA or sOVA resulted in a reduction of both the anti-OVA IgE level and the IgG1/IgG2a ratio. Moreover, ASIT with sOVA increased the IFN-γ level in supernatants after splenocyte stimulation with OVA. Histologic analysis of skin samples from the sites of allergen application showed that ASIT improved the histologic picture by decreasing allergic inflammation in comparison with untreated mice. These data suggest that ASIT with a succinylated allergen represents promising approach for the treatment of AD. 相似文献
107.
Gregory A. Prussia Krista A. Shisler Oleg A. Zadvornyy Bennett R. Streit Jennifer L. DuBois John W. Peters 《The Journal of biological chemistry》2021,297(2)
The 2-ketopropyl-coenzyme M oxidoreductase/carboxylase (2-KPCC) enzyme is the only member of the disulfide oxidoreductase (DSOR) family of enzymes, which are important for reductively cleaving S–S bonds, to have carboxylation activity. 2-KPCC catalyzes the conversion of 2-ketopropyl-coenzyme M to acetoacetate, which is used as a carbon source, in a controlled reaction to exclude protons. A conserved His–Glu motif present in DSORs is key in the protonation step; however, in 2-KPCC, the dyad is substituted by Phe–His. Here, we propose that this difference is important for coupling carboxylation with C–S bond cleavage. We substituted the Phe–His dyad in 2-KPCC to be more DSOR like, replacing the phenylalanine with histidine (F501H) and the histidine with glutamate (H506E), and solved crystal structures of F501H and the double variant F501H_H506E. We found that F501 protects the enolacetone intermediate from protons and that the F501H variant strongly promotes protonation. We also provided evidence for the involvement of the H506 residue in stabilizing the developing charge during the formation of acetoacetate, which acts as a product inhibitor in the WT but not the H506E variant enzymes. Finally, we determined that the F501H substitution promotes a DSOR-like charge transfer interaction with flavin adenine dinucleotide, eliminating the need for cysteine as an internal base. Taken together, these results indicate that the 2-KPCC dyad is responsible for selectively promoting carboxylation and inhibiting protonation in the formation of acetoacetate. 相似文献
108.
Alexey A. Zeifman Fedor N. Novikov Victor S. Stroylov Oleg V. Stroganov Ghermes G. Chilov Alexander Y. Skoblov Anatoly I. Miroshnikov Yuri S. Skoblov 《FEBS letters》2014
2,3-Dihydroxy-quinoxaline, a small molecule that promotes ATPase catalytic activity of Herpes Simplex Virus thymidine kinase (HSV-TK), was identified by virtual screening. This compound competitively inhibited HSV-TK catalyzed phosphorylation of acyclovir with Ki = 250 μM (95% CI: 106–405 μM) and dose-dependently increased the rate of the ATP hydrolysis with KM = 112 μM (95% CI: 28–195 μM). The kinetic scheme consistent with this experimental data is proposed. 相似文献
109.
Rick?K. Huang Ulrich Baxa Gudrun Aldrian Abdullah?B. Ahmed Joseph?S. Wall Naoko Mizuno Oleg Antzutkin Alasdair?C. Steven Andrey?V. Kajava 《Biophysical journal》2014,106(10):2134-2142
The established correlation between neurodegenerative disorders and intracerebral deposition of polyglutamine aggregates motivates attempts to better understand their fibrillar structure. We designed polyglutamines with a few lysines inserted to overcome the hindrance of extreme insolubility and two D-lysines to limit the lengths of β-strands. One is 33 amino acids long (PolyQKd-33) and the other has one fewer glutamine (PolyQKd-32). Both form well-dispersed fibrils suitable for analysis by electron microscopy. Electron diffraction confirmed cross-β structures in both fibrils. Remarkably, the deletion of just one glutamine residue from the middle of the peptide leads to substantially different amyloid structures. PolyQKd-32 fibrils are consistently 10–20% wider than PolyQKd-33, as measured by negative staining, cryo-electron microscopy, and scanning transmission electron microscopy. Scanning transmission electron microscopy analysis revealed that the PolyQKd-32 fibrils have 50% higher mass-per-length than PolyQKd-33. This distinction can be explained by a superpleated β-structure model for PolyQKd-33 and a model with two β-solenoid protofibrils for PolyQKd-32. These data provide evidence for β-arch-containing structures in polyglutamine fibrils and open future possibilities for structure-based drug design. 相似文献
110.
Gennadii Petrovich Gusev Natalia Ivanovna Agalakova 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》2010,180(3):385-391
Recently (Agalakova and Gusev in J Comp Physiol 179:443–450, 2009), we demonstrated that the activity of K–Cl cotransport (KCC) in frog red blood cells is inhibited under stimulation of protein
kinase C (PKC) with phorbol ester PMA (12-myristate-13-acetate). Present work was performed to uncover possible implication
of protein kinases and protein phosphatases (PPs) in the regulation of baseline and volume-dependent KCC activity in these
cells. K+ influx was estimated as 86Rb uptake by the cells in isotonic or hypotonic media in the presence of ouabain, K+ efflux was determined as the difference between K+ loss by the cells incubated in parallel in isotonic or hypotonic K+-free Cl−- and NO3
−-media. Swelling of the cells in hypotonic medium was accompanied by approximately 50% activation of Cl-dependent K+ influx and efflux. Protein tyrosine kinase (PTK) inhibitor genistein (0.1 mM) stably and considerably (up to 89%) suppressed
both baseline and volume-dependent KCC activity in each direction. Other PTK blockers (tyrphostin 23 and quercetin) had no
influence on KCC activity in frog erythrocytes. PKC inhibitor chelerythrine (20 μM) and both PP inhibitors, fluoride (5 mM)
and okadaic acid (1 μM), reduced KCC activity by 25–70%. Neither basal nor swelling-activated KCC in frog erythrocytes was
affected by PKC inhibitor staurosporine (1 μM). Based on the previous and present results, we can suggest that the main role
in the maintenance of basal and volume-dependent KCC activity in frog erythrocytes belongs to PTKs and PPs, whereas PKC is
a negative regulator of this ion system. 相似文献