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981.
Mauricio Torres Danilo B. Medinas José Manuel Matamala Ute Woehlbier Víctor Hugo Cornejo Tatiana Solda Catherine Andreu Pablo Rozas Soledad Matus Natalia Mu?oz Carmen Vergara Luis Cartier Claudio Soto Maurizio Molinari Claudio Hetz 《The Journal of biological chemistry》2015,290(39):23631-23645
Although the accumulation of a misfolded and protease-resistant form of the prion protein (PrP) is a key event in prion pathogenesis, the cellular factors involved in its folding and quality control are poorly understood. PrP is a glycosylated and disulfide-bonded protein synthesized at the endoplasmic reticulum (ER). The ER foldase ERp57 (also known as Grp58) is highly expressed in the brain of sporadic and infectious forms of prion-related disorders. ERp57 is a disulfide isomerase involved in the folding of a subset of glycoproteins in the ER as part of the calnexin/calreticulin cycle. Here, we show that levels of ERp57 increase mainly in neurons of Creutzfeldt-Jacob patients. Using gain- and loss-of-function approaches in cell culture, we demonstrate that ERp57 expression controls the maturation and total levels of wild-type PrP and mutant forms associated with human disease. In addition, we found that PrP physically interacts with ERp57, and also with the closest family member PDIA1, but not ERp72. Furthermore, we generated a conditional knock-out mouse for ERp57 in the nervous system and detected a reduction in the steady-state levels of the mono- and nonglycosylated forms of PrP in the brain. In contrast, ERp57 transgenic mice showed increased levels of endogenous PrP. Unexpectedly, ERp57 expression did not affect the susceptibility of cells to ER stress in vitro and in vivo. This study identifies ERp57 as a new modulator of PrP levels and may help with understanding the consequences of ERp57 up-regulation observed in human disease. 相似文献
982.
Cinnamyl alcohol dehydrogenases in the mesocarp of ripening fruit of Prunus persica genotypes with different flesh characteristics: changes in activity and protein and transcript levels
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983.
Franco Cardone Serena Principe Maria Eugenia Schininà Bruno Maras Sabina Capellari Piero Parchi Silvio Notari Laura Di Francesco Anna Poleggi Roberta Galeno Ramona Vinci Vittorio Mellina Susanna Almonti Anna Ladogana Maurizio Pocchiari 《Biochemical and biophysical research communications》2014
Creutzfeldt–Jakob disease (CJD) is a neurodegenerative disorder characterized by the deposition of the pathological conformer (PrPCJD) of the host encoded cellular prion protein (PrPC). In genetic CJD associated with V210I or R208H PrP substitutions, the pathogenic role of mutant residues is still poorly understood. To understand how V210I or R208H PrP mutations facilitate the development of the disease, we determined by mass spectrometry the quantitative ratio of mutant/wild-type PrPCJD allotypes in brains from affected subjects. We found that the mutant PrPCJD allotypes moderately exceeds of 2- or 3-fold the amount of the wild-type counterpart suggesting that these mutations mainly exert their pathogenic effect on the onset of the pathogenic cascade. 相似文献
984.
985.
The Ever Changing Moods of Calmodulin: How Structural Plasticity Entails Transductional Adaptability
Alvaro Villarroel Maurizio Taglialatela Ganeko Bernardo-Seisdedos Alessandro Alaimo Jon Agirre Araitz Alberdi Carolina Gomis-Perez Maria Virginia Soldovieri Paolo Ambrosino Covadonga Malo Pilar Areso 《Journal of molecular biology》2014
The exceptional versatility of calmodulin (CaM) three-dimensional arrangement is reflected in the growing number of structural models of CaM/protein complexes currently available in the Protein Data Bank (PDB) database, revealing a great diversity of conformations, domain organization, and structural responses to Ca2 +. Understanding CaM binding is complicated by the diversity of target proteins sequences. Data mining of the structures shows that one face of each of the eight CaM helices can contribute to binding, with little overall difference between the Ca2 + loaded N- and C-lobes and a clear prevalence of the C-lobe low Ca2 + conditions. The structures reveal a remarkable variety of configurations where CaM binds its targets in a preferred orientation that can be reversed and where CaM rotates upon Ca2 + binding, suggesting a highly dynamic metastable relation between CaM and its targets. Recent advances in structure–function studies and the discovery of CaM mutations being responsible for human diseases, besides expanding the role of CaM in human pathophysiology, are opening new exciting avenues for the understanding of the how CaM decodes Ca2 +-dependent and Ca2 +-independent signals. 相似文献
986.
Federica Gilardi Marco Giudici Nico Mitro Omar Maschi Uliano Guerrini Gianpaolo Rando Adriana Maggi Gaia Cermenati Antonio Laghezza Fulvio Loiodice Giorgio Pochetti Antonio Lavecchia Donatella Caruso Emma De Fabiani Krister Bamberg Maurizio Crestani 《The Journal of biological chemistry》2014,289(10):6908-6920
987.
Fabio Abeni Maurizio Capelletti Giuseppina Maria Terzano Claudia Federici Marisanna Speroni Francesca Petrera Aldo Dal Prà Cesare Galli Roberto Duchi Giovanna Lazzari Giacomo Pirlo Riccardo Aleandri 《Theriogenology》2014
The aim of this article was to compare plasma estrone sulfate (E1SO4), clinical biochemistry, and milk yield of dairy cows carrying a female fetus from a bull (BULL) or from its clone (CLONE), evaluating also the relationship between the former variables and the birth weight of the newborn. Sixteen recipient dairy Friesian heifers (10 BULL and 7 CLONE) received a female embryo, obtained by in vitro embryo production and sexing by polymerase chain reaction with the semen of the BULL or the CLONE. Blood samples on all cows were obtained before feed distribution in the morning from jugular vein from 4 weeks before to 4 weeks after calving, to be analyzed for metabolic profile. The samples from late gestation were also analyzed for E1SO4 concentration. To separately assess the effect of calf birth weight (CBW), data were categorized as follows: low (<39 kg; BWT-A), mid (39–46 kg; BWT-B), and high (>46 kg; BWT-C). The plasma concentrations of β-hydroxybutyric acid (BHB, P = 0.019), Na (P = 0.002), Cl (P = 0.026), strong cation–anion balance (P = 0.020), total bilirubin (P = 0.054), and α1-globulin (P = 0.044) were higher in prepartum BULL recipients than those in CLONE, whereas BHB (P = 0.021) and Mg (P = 0.090) were higher in postpartum BULL recipients, while no differences were recorded in the remaining postpartum parameters. The CBW class had significant interaction with week of gestation on antepartum plasma estrone sulfate (P = 0.021), whereas CBW per se affected antepartum plasma BHB (P = 0.021), and nonesterified fatty acids (NEFA; P = 0.011) being higher in BWT-C which also had the lower NEFA concentration during postpartum. Milk yield was unaffected by the sire used, both for quantitative and qualitative aspects. Cows carrying heavier fetus (BWT-C) had a different lactation affected by month compared with the other 2 CBW groups. From these results, there were no differences between BULL and CLONE recipients. Estrone sulfate, BHB, and NEFA may be used to predict CBW and provide different nutritional management during gestation. 相似文献
988.
Gianluca Serafini Maurizio Pompili Katelin F. Hansen Karl Obrietan Yogesh Dwivedi Noam Shomron Paolo Girardi 《Cellular and molecular neurobiology》2014,34(1):17-30
Major depressive disorders are common and disabling conditions associated with significant psychosocial impairment and suicide risk. At least 3–4 % of all depressive individuals die by suicide. Evidence suggests that small non-coding RNAs, in particular microRNAs (miRNAs), play a critical role in major affective disorders as well as suicide. We performed a detailed review of the current literature on miRNAs and their targets in major depression and related disorders as well as suicidal behavior, with a specific focus on miR-185 and miR-491-3p, which have been suggested to participate in the pathogenesis of major depression and/or suicide. miRNAs play a fundamental role in the development of the brain. Several miRNAs are reported to influence neuronal and circuit formation by negatively regulating gene expression. Global miRNA reduced expression was found in the prefrontal cortex of depressed suicide completers when compared to that of nonpsychiatric controls who died of other causes. One particular miRNA, miR-185, was reported to regulate TrkB-T1, which has been associated with suicidal behavior upon truncation. Furthermore, cAMP response element-binding protein–brain-derived neurotrophic factor pathways may regulate, through miRNAs, the homeostasis of neural and synaptic pathways playing a crucial role in major depression. miRNAs have gained attention as key players involved in nervous system development, physiology, and disease. Further evidence is needed to clarify the exact role that miRNAs play in major depression and related disorders and suicidal behavior. 相似文献
989.
Jennifer Baraka-Vidot Giovanna Navarra Maurizio Leone Emmanuel Bourdon Valeria Militello Philippe Rondeau 《Biochimica et Biophysica Acta (BBA)/General Subjects》2014
Background
Metal ions such as copper or zinc are involved in the development of neurodegenerative pathologies and metabolic diseases such as diabetes mellitus. Albumin structure and functions are impaired following metal- and glucose-mediated oxidative alterations. The aim of this study was to elucidate effects of Cu(II) and Zn(II) ions on glucose-induced modifications in albumin by focusing on glycation, aggregation, oxidation and functional aspects.Methods
Aggregation and conformational changes in albumin were monitored by spectroscopy, fluorescence and microscopy techniques. Biochemical assays such as carbonyl, thiol groups, albumin-bound Cu, fructosamine and amine group measurements were used. Cellular assays were used to gain functional information concerning antioxidant activity of oxidized albumins.Results
Both metals promoted inhibition of albumin glycation associated with an enhanced aggregation and oxidation process. Metal ions gave rise to the formation of β-amyloid type aggregates in albumin exhibiting impaired antioxidant properties and toxic activity to murine microglia cells (BV2). The differential efficiency of both metal ions to inhibit albumin glycation, to promote aggregation and to affect cellular physiology is compared.Conclusions and general significance
Considering the key role of oxidized protein in pathology complications, glycation-mediated and metal ion-induced impairment of albumin properties might be important parameters to be followed and fought. 相似文献990.
Irene Samengo Diego Currò Vincenzo Barrese Maurizio Taglialatela Maria Martire 《Neurochemical research》2014,39(5):901-910
Large conductance, calcium-activated potassium channels [big potassium (BK) channel] consist of a tetramer of pore-forming α-subunit and distinct accessory β-subunits (β1–4) that modify the channel’s properties. In this study, we analyzed the effects of BK channel activators and blockers on glutamate and γ-aminobutyric acid (GABA) release from synaptosomes isolated from the cerebral cortices or trigeminal caudal nuclei (TCN) of rats. Real-time polymerase chain reaction was used to characterize BK channel α and β(1–4) subunit expression in the cortex and in the trigeminal ganglia (TG), whose neurons project primary terminal afferents into the TCN. Immunocytochemistry was used to localize these subunits on cortical and TCN synaptosomes. The BK channels regulating [3H]D-aspartate release from primary afferent nerve terminals projecting into the TCN displayed limited sensitivity to iberiotoxin, whereas those expressed on cortical synaptosomes were highly sensitive to this toxin. BK channels did not appear to be present on GABAergic nerve terminals from the TCN since [3H]-γ-aminobutyric acid release in this model was unaffected by BK channel activators or blockers. Gene expression studies revealed expression levels of the α subunit in the TG that were only 31.2 ± 2.1 % of those found in cortical tissues. The β4 subunit was the accessory subunit expressed most abundantly in both the cortex and TG. Levels of β1 and β2 were low in both these areas although β2 expression in the TG was higher than that found in the cortex. Immunocytochemistry experiments showed that co-localization of α and β4 subunits (the accessory subunit most abundantly expressed in both brain areas) was more common in TCN synaptosomes than in cortical synaptosomes. On the basis of these findings, it is reasonable to hypothesize that BK channels expressed on glutamatergic terminals in the TCN and cortex have distinct pharmacological profiles, which probably reflect different α and β subunit combinations. Channels in the cortex seem to be composed mainly of α subunits and to a lesser degree by α and β4 subunits, whereas in the TG the α + β4 combination seems to prevail (although α and/or α + β2 channels cannot be excluded). In light of the BK channels’ selective control of excitatory transmission and their pharmacological diversity, their effects on primary glutamatergic afferents projecting to TCN represent a potential target for drug therapy of migraines and other types of orofacial pain. 相似文献