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11.
Tomàs Pinós Mario Marotta Eduard Gallardo Isabel Illa Jorge Díaz-Manera Emiliano Gonzalez-Vioque Elena García-Arumí Antoni L. Andreu Ramon Martí 《Mitochondrion》2011,11(1):228-233
We report a heteroplasmic novel mutation m.5636T>C in the mt-tRNAAla in a patient with bilateral ptosis and ophthalmoparesis in whom a muscle biopsy showed cytochrome c oxdidase (COX) negative and ragged red fibers. Using laser capture microdissection we have isolated COX negative fibers and COX positive fibers from the muscle of the patient and determined that the mutation load was clearly increased in COX negative muscle fibers. Additionally, the mutated m.5636T nucleotide is conserved in all the mammal and non-mammal species analyzed and might be structurally relevant as it is located in a position involved in the formation of tertiary structure of canonical mitochondrial tRNAs. 相似文献
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A 330 bp region of the spinach nitrite reductase gene promoter directs nitrate-inducible tissue-specific expression in transgenic tobacco 总被引:4,自引:0,他引:4
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Christian Schimper Rupert Keckeis Eduard Burtscher Avinash P. Manian 《Biocatalysis and Biotransformation》2013,31(5-6):383-389
Cellulosic fabric samples of cotton, viscose, lyocell and modal were pretreated with steam and dry heat in the range of 100–190°C. The samples were then treated with a Trichoderma reesei cellulase preparation (total culture filtrate – TC), with mechanical agitation, at a high enzyme dosage of 75% by weight of fabric, for 8 hours. Generally, viscose proved to be easily degradable, followed by cotton and modal. The degree of hydrolysis was the least for Lyocell. Dry heat pretreatments exerted a lower influence on degradation rate than steam pretreatments which showed a distinct maximum at a steam temperature of 130°C. The hydrolysis rate varied strongly depending on treatment conditions and fibre type. Water retention values in treated substrates were changed by up to 20% of initial values. 相似文献
16.
Mingels AM Joosen IA Versteylen MO Laufer EM Winkens MH Wildberger JE Van Dieijen-Visser MP Hofstra L 《PloS one》2012,7(4):e35059
Background
Recent studies have demonstrated the association between increased concentrations of high-sensitivity cardiac troponin T (hs-cTnT) and the incidence of myocardial infarction, heart failure, and mortality. However, most prognostic studies to date focus on the value of hs-cTnT in the elderly or general population. The value of hs-cTnT in symptomatic patients visiting the outpatient department remains unclear. The aim of this study was to investigate the prognostic value of hs-cTnT as a biomarker in patients with symptoms of chest discomfort suspected for coronary artery disease and to assess its additional value in combination with other risk stratification tools in predicting cardiac events.Methods
We studied 1,088 patients (follow-up 2.2±0.8 years) with chest discomfort who underwent coronary calcium scoring and coronary CT-angiography. Traditional cardiovascular risk factors and concentrations of hs-cTnT, N-terminal pro-brain-type natriuretic peptide (NT-proBNP) and high-sensitivity C-reactive protein (hsCRP) were assessed. Study endpoint was the occurrence of late coronary revascularization (>90 days), acute coronary syndrome, and cardiac mortality.Results
Hs-cTnT was a significant predictor for the composite endpoint (highest quartile [Q4]>6.7 ng/L, HR 3.55; 95%CI 1.88–6.70; P<0.001). Survival analysis showed that hs-cTnT had significant predictive value on top of current risk stratification tools (Chi-square change P<0.01). In patients with hs-cTnT in Q4 versusConclusions
Hs-cTnT is a useful prognostic biomarker in patients with chest discomfort suspected for coronary artery disease. In addition, hs-cTnT was an independent predictor for cardiac events when corrected for cardiovascular risk profiling, calcium score and CT-angiography results. 相似文献17.
Hundsrucker C Krause G Beyermann M Prinz A Zimmermann B Diekmann O Lorenz D Stefan E Nedvetsky P Dathe M Christian F McSorley T Krause E McConnachie G Herberg FW Scott JD Rosenthal W Klussmann E 《The Biochemical journal》2006,396(2):297-306
PKA (protein kinase A) is tethered to subcellular compartments by direct interaction of its regulatory subunits (RI or RII) with AKAPs (A kinase-anchoring proteins). AKAPs preferentially bind RII subunits via their RII-binding domains. RII-binding domains form structurally conserved amphipathic helices with unrelated sequences. Their binding affinities for RII subunits differ greatly within the AKAP family. Amongst the AKAPs that bind RIIalpha subunits with high affinity is AKAP7delta [AKAP18delta; K(d) (equilibrium dissociation constant) value of 31 nM]. An N-terminally truncated AKAP7delta mutant binds RIIalpha subunits with higher affinity than the full-length protein presumably due to loss of an inhibitory region [Henn, Edemir, Stefan, Wiesner, Lorenz, Theilig, Schmidtt, Vossebein, Tamma, Beyermann et al. (2004) J. Biol. Chem. 279, 26654-26665]. In the present study, we demonstrate that peptides (25 amino acid residues) derived from the RII-binding domain of AKAP7delta bind RIIalpha subunits with higher affinity (K(d)=0.4+/-0.3 nM) than either full-length or N-terminally truncated AKAP7delta, or peptides derived from other RII binding domains. The AKAP7delta-derived peptides and stearate-coupled membrane-permeable mutants effectively disrupt AKAP-RII subunit interactions in vitro and in cell-based assays. Thus they are valuable novel tools for studying anchored PKA signalling. Molecular modelling indicated that the high affinity binding of the amphipathic helix, which forms the RII-binding domain of AKAP7delta, with RII subunits involves both the hydrophobic and the hydrophilic faces of the helix. Alanine scanning (25 amino acid peptides, SPOT technology, combined with RII overlay assays) of the RII binding domain revealed that hydrophobic amino acid residues form the backbone of the interaction and that hydrogen bond- and salt-bridge-forming amino acid residues increase the affinity of the interaction. 相似文献
18.
Microtubules of guard cells are light sensitive 总被引:7,自引:0,他引:7
Guard cells of stomata are characterized by ordered bundles of microtubules radiating from the ventral side toward the dorsal side of the cylindrical cell. It was suggested that microtubules play a role in directing the radial arrangement of the cellulose micro-fibrils of guard cells. However, the role of microtubules in daily cycles of opening and closing of stomata is not clear. The organization of microtubules in guard cells of Commelina communis leaves was studied by analysis of three-dimensional immunofluorescent images. It was found that while guard cell microtubules in the epidermis of leaves incubated in the light were organized in parallel, straight and dense bundles, in the dark they were less straight and oriented randomly near the stomatal pore. The effect of blue and red light on the organization of guard cell microtubules resembled the effects of white light and dark respectively. When stomata were induced to open in the dark with fusicoccin, microtubules remained in the dark configuration. Furthermore, when incubated in the light, guard cell microtubules were more resistant to oryzalin. Similarly, microtubules of Arabidopsis guard cells, expressing green fluorescent protein-tubulin alpha 6, were disorganized in the dark, but were organized in parallel arrays in the presence of white light. The dynamics of microtubule rearrangement upon transfer of intact leaves from dark to light was followed in single stomata, showing that an arrangement of microtubules typical for light conditions was obtained after 1 h in the light. Our data suggest that microtubule organization in guard cells is responsive to light signals. 相似文献
19.
Bitto E Bingman CA Kondrashov DA McCoy JG Bannen RM Wesenberg GE Phillips GN 《Proteins》2008,70(1):93-104
Soluble N-ethylmaleimide-sensitive factor attachment protein gamma (gamma-SNAP) is a member of an eukaryotic protein family involved in intracellular membrane trafficking. The X-ray structure of Brachydanio rerio gamma-SNAP was determined to 2.6 A and revealed an all-helical protein comprised of an extended twisted-sheet of helical hairpins with a helical-bundle domain on its carboxy-terminal end. Structural and conformational differences between multiple observed gamma-SNAP molecules and Sec17, a SNAP family protein from yeast, are analyzed. Conformational variation in gamma-SNAP molecules is matched with great precision by the two lowest frequency normal modes of the structure. Comparison of the lowest-frequency modes from gamma-SNAP and Sec17 indicated that the structures share preferred directions of flexibility, corresponding to bending and twisting of the twisted sheet motif. We discuss possible consequences related to the flexibility of the SNAP proteins for the mechanism of the 20S complex disassembly during the SNAP receptors recycling. 相似文献
20.
Csilla Krausz Claudia Giachini Deborah Lo Giacco Fabrice Daguin Chiara Chianese Elisabet Ars Eduard Ruiz-Castane Gianni Forti Elena Rossi 《PloS one》2012,7(10)