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31.
Bonsegna S Slocombe SP De Bellis L Baker A 《Archives of biochemistry and biophysics》2005,443(1-2):74-81
Long-chain acyl-CoA synthetases (LACSs) activate fatty acids for further metabolism and are encoded by a multi-gene family in Arabidopsis. AtLACS6 possesses a type 2 (PTS2) peroxisomal targeting sequence, whilst AtLACS7 has both a type 1 and type 2 peroxisomal targeting sequence. AtLACS7 was used as bait in a yeast two-hybrid screen. Multiple clones of the PTS1 receptor PEX5 were isolated. Quantitative beta-galactosidase assay indicated that full-length PEX5 interacts with AtLACS7 with higher affinity than the TPR domains alone. The interaction between PEX5 and AtLACS7 was confirmed by co-immunoprecipitation and shown to be specific for the PTS1, therefore the AtLACS7 PTS1 is accessible to bind PEX5 in the full-length AtLACS7 protein. The expression profile of AtLACS6, AtLACS7, AtPEX5, and AtPEX7 revealed that AtLACS6 and 7 have distinct patterns of expression and we speculate that the possession of two targeting signals may be advantageous for the import of AtLACS7 when receptors may be limiting. 相似文献
32.
Stefania Casagrande Cor Dijkstra James Tagliavini Vivian C. Goerlich Ton G. G. Groothuis 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》2011,197(1):1-13
Recent studies have demonstrated that carotenoid-based traits are under the control of testosterone (T) by up-regulation of
carotenoid carriers (lipoproteins) and/or tissue-specific uptake of carotenoids. T can be converted to dihydrotestosterone
(DHT) and estradiol (E2), and variation in conversion rate may partly explain some contradictory findings in the literature.
Moreover, most studies on the effect of T on sexual signals have focused on the male sex only, while in many species females
show the same signal, albeit to a lesser extent. We studied the effects of T, DHT, and E2 treatment in male and female diamond
doves Geopelia cuneata in which both sexes have an enlarged red eye ring, which is more pronounced in males. We first showed that this periorbital
ring contains very high concentration of carotenoids, of which most are lutein esters. Both T and DHT were effective in enhancing
hue, UV-chroma and size in both sexes, while E2 was ineffective. However, E2 dramatically increased the concentration of circulating
lipoproteins. We conclude that in both sexes both color and size of the secondary sexual trait are androgen dependent. The
action of androgens is independent of lipoproteins regulation. Potential mechanisms and their consequences for trade-off are
discussed. 相似文献
33.
HDACs, histone deacetylation and gene transcription: from molecular biology to cancer therapeutics 总被引:16,自引:0,他引:16
Histone deacetylases (HDACs) and histone acetyl transferases (HATs) are two counteracting enzyme families whose enzymatic activity controls the acetylation state of protein lysine residues, notably those contained in the N-terminal extensions of the core histones. Acetylation of histones affects gene expression through its influence on chromatin conformation. In addition, several non-histone proteins are regulated in their stability or biological function by the acetylation state of specific lysine residues. HDACs intervene in a multitude of biological processes and are part of a multiprotein family in which each member has its specialized functions. In addition, HDAC activity is tightly controlled through targeted recruitment, protein-protein interactions and post-translational modifications. Control of cell cycle progression, cell survival and differentiation are among the most important roles of these enzymes. Since these processes are affected by malignant transformation, HDAC inhibitors were developed as antineoplastic drugs and are showing encouraging efficacy in cancer patients. 相似文献
34.
35.
The Cercopithecini, or African guenon monkeys, are one of the most diverse clades of living primates and comprise the most species‐rich clade of Catarrhini. Species identity is announced by flamboyant coloration of the facial and genital regions and, more cryptically, by vigorous chromosomal rearrangements among taxa. Beneath the skin, however, these animals are skeletally conservative and show low levels of genetic sequence divergence consonant with recent divergence between congeneric species. The guenons clearly demonstrate that morphological, cytogenetic, and reproductive differentiation proceed at different rates during speciation. We review diverse kinds of data in an effort to understand this conundrum. 相似文献
36.
Emma-Jo Hayton Annie Rose Umar Ibrahimsa Mariarosaria Del Sorbo Stefania Capone Alison Crook Antony P. Black Lucy Dorrell Tomá? Hanke 《PloS one》2014,9(7)
Trial Design
HIV-1 vaccine development has advanced slowly due to viral antigenic diversity, poor immunogenicity and recently, safety concerns associated with human adenovirus serotype-5 vectors. To tackle HIV-1 variation, we designed a unique T-cell immunogen HIVconsv from functionally conserved regions of the HIV-1 proteome, which were presented to the immune system using a heterologous prime-boost combination of plasmid DNA, a non-replicating simian (chimpanzee) adenovirus ChAdV-63 and a non-replicating poxvirus, modified vaccinia virus Ankara. A block-randomized, single-blind, placebo-controlled phase I trial HIV-CORE 002 administered for the first time candidate HIV-1- vaccines or placebo to 32 healthy HIV-1/2-uninfected adults in Oxford, UK and elicited high frequencies of HIV-1-specific T cells capable of inhibiting HIV-1 replication in vitro. Here, detail safety and tolerability of these vaccines are reported.Methods
Local and systemic reactogenicity data were collected using structured interviews and study-specific diary cards. Data on all other adverse events were collected using open questions. Serum neutralizing antibody titres to ChAdV-63 were determined before and after vaccination.Results
Two volunteers withdrew for vaccine-unrelated reasons. No vaccine-related serious adverse events or reactions occurred during 190 person-months of follow-up. Local and systemic events after vaccination occurred in 27/32 individuals and most were mild (severity grade 1) and predominantly transient (<48 hours). Myalgia and flu-like symptoms were more strongly associated with MVA than ChAdV63 or DNA vectors and more common in vaccine recipients than in placebo. There were no intercurrent HIV-1 infections during follow-up. 2/24 volunteers had low ChAdV-63-neutralizing titres at baseline and 7 increased their titres to over 200 with a median (range) of 633 (231-1533) post-vaccination, which is of no safety concern.Conclusions
These data demonstrate safety and good tolerability of the pSG2.HIVconsv DNA, ChAdV63.HIVconsv and MVA.HIVconsv vaccines and together with their high immunogenicity support their further development towards efficacy studies.Trial Registration
ClinicalTrials.gov NCT01151319相似文献37.
Pasqualina Woodrow Giovanni Pontecorvo Stefania Fantaccione Amodio Fuggi Ioannis Kafantaris Danila Parisi Petronia Carillo 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2010,121(2):311-322
Long terminal repeat retrotransposons are the most abundant mobile elements in the plant genome and play an important role in the genome reorganization induced by environmental challenges. Their success depends on the ability of their promoters to respond to different signaling pathways that regulate plant adaptation to biotic and abiotic stresses. We have isolated a new Ty1-copia-like retrotransposon, named Ttd1a from the Triticum durum L. genome. To get insight into stress activation pathways in Ttd1a, we investigated the effect of salt and light stresses by RT-PCR and S-SAP profiling. We screened for Ttd1a insertion polymorphisms in plants grown to stress and showed that one new insertion was located near the resistance gene. Our analysis showed that the activation and mobilization of Ttd1a was controlled by salt and light stresses, which strengthened the hypothesis that stress mobilization of this element might play a role in the defense response to environmental stresses. 相似文献
38.
Stefania Piantavigna Patricia Czihal Adam Mechler Monique Richter Ralf Hoffmann Lisandra L. Martin 《International journal of peptide research and therapeutics》2009,15(2):139-146
Apidaecin peptides from Apis mellifera hemolymph are believed to attack intracellular bacterial targets. Our in vivo results for apidaecins 1a and 1b confirm that
bacterial activity is non-lytic, however, the manner in which these peptides pass through the cell membrane to exert this
activity is unknown. These data are combined with fluorescence (dye leakage) and quartz crystal microbalance studies to investigate
the membrane interaction for these two wildtype peptides. It was found that the peptides penetrate the membrane in a trans-membrane
manner. The amount of peptide uptake by the membrane is proportional to the concentration of the peptide, however, this appears
to be a dynamic equilibrium which can be almost completely reversed by addition of buffer medium. Interestingly, a small residual
mass remains within the membrane and the amount of peptide remaining in the membrane is a function of the buffer-salt concentration
viz. in high salt, the residual peptide mass remaining is small whereas at low salt concentration, a larger mass of peptide
remains bound. These results support a direct membrane penetration mechanism by the wild type apidaecins 1a and 1b. In both
cases the peptide–membrane interaction has a negligible effect on the membrane, although, in high salt a permanent change
in the membrane does occur at the highest peptide concentration which does not recover following peptide removal.
Stefania Piantavigna and Patricia Czihal contributed equally to this article. 相似文献
39.
In celiac disease (CD), gluten, the disease-inducing toxic component in wheat, induces the secretion of IgA-class autoantibodies which target tissue transglutaminase (tTG). These autoantibodies are produced in the small-intestinal mucosa, and, during gluten consumption, they can also be detected in patients' serum but disappear slowly from the circulation on a gluten-free diet. Interestingly, after adoption of a gluten-free diet the serum autoantibodies disappear from the circulation more rapidly than the small-intestinal mucosal autoantibody deposits. The finding of IgA deposits on extracellular tTG in the liver, kidney, lymph nodes and muscles of patients with CD indicates that tTG is accessible to the gut-derived autoantibodies. Although the specific autoantibody response directed against tTG is very characteristic in celiac patients, their role in the immunopathology of the celiac mucosal lesion is a matter of debate. Here we report a brief summary of anti-tTG antibody effects demonstrating that these antibodies are functional and not mere bystanders in the disease pathogenesis. In fact, they inhibit intestinal epithelial cell differentiation, induce intestinal epithelial cell proliferation, increase epithelial permeability and activate monocytes and disturb angiogenesis. 相似文献
40.
Beste Ozben Evrim Dursun Emanuela Monari Aurora Cuoghi Stefania Bergamini Aldo Tomasi Tomris Ozben 《Molecular and cellular biochemistry》2009,331(1-2):9-17
There is a great need for the identification of biomarkers for the early diagnosis of atherosclerosis and the agents to prevent its progression. The aim of this study was to explore the effect of 24 week of nebivolol (a third-generation vasodilatory beta-blocker) treatment on serum protein profiles in Apo E?/? mice during atherosclerosis progression. Nebivolol treated and non-treated (the control group) groups consisted of 10 genetically modified homozygous Apo E?/? mice. Proteomic analyses were performed using surface-enhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF MS) in the serum samples from the nebivolol treated and non-treated Apo E?/? mice. The protein profiles obtained using three different chips, CM10 (weak cation-exchange), H50 (reverse phase), and IMAC30-Cu2+ (immobilized metal affinity capture) were statistically analyzed using the ProteinChip data manager 3.0 program. At the end of 24 week of nebivolol-treatment period, a total of 662 protein/peptide clustering peaks were detected using 12 different conditions and reading with high and low intensity laser energy. The highest total number of protein/peptide clusters was found on H50 chip array. The peak intensities of 95 of the 662 protein/peptide clusters were significantly different in the nebivolol-treated atherosclerotic group in comparison to the non-treated control mice groups (P < 0.05). Forty-three protein/peptides were up-regulated (high signal intensity) while 52 protein/peptides had lower signal intensity (down-regulated) in the nebivolol-treated atherosclerotic group. The proteomic profiles of nebivolol-treated Apo E?/? mice were different than the control group indicating a potential role of nebivolol in atherosclerosis. Our study contributes to understand the efficacy of nebivolol on serum protein/peptide profiles during atherosclerosis development. 相似文献