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91.
MicroRNA-486-3p Regulates γ-Globin Expression in Human Erythroid Cells by Directly Modulating BCL11A
Valentina Lulli Paolo Romania Ornella Morsilli Paolo Cianciulli Marco Gabbianelli Ugo Testa Alessandro Giuliani Giovanna Marziali 《PloS one》2013,8(4)
MicroRNAs (miRNAs) play key roles in modulating a variety of cellular processes through repression of mRNAs target. The functional relevance of microRNAs has been proven in normal and malignant hematopoiesis. While analyzing miRNAs expression profile in unilineage serum-free liquid suspension unilineage cultures of peripheral blood CD34+ hematopoietic progenitor cells (HPCs) through the erythroid, megakaryocytic, granulocytic and monocytic pathways, we identified miR-486-3p as mainly expressed within the erythroid lineage. We showed that miR-486-3p regulates BCL11A expression by binding to the extra-long isoform of BCL11A 3′UTR. Overexpression of miR-486-3p in erythroid cells resulted in reduced BCL11A protein levels, associated to increased expression of γ-globin gene, whereas inhibition of physiological miR-486-3p levels increased BCL11A and, consequently, reduced γ-globin expression. Thus, miR-486-3p regulating BCL11A expression might contributes to fetal hemoglobin (HbF) modulation and arise the question as to what extent this miRNA might contribute to different HbF levels observed among β-thalassemia patients. Erythroid cells, differentiated from PB CD34+ cells of a small cohort of patients affected by major or intermedia β-thalassemia, showed miR-486-3p levels significantly higher than those observed in normal counterpart. Importantly, in these patients, miR-486-3p expression correlates with increased HbF synthesis. Thus, our data indicate that miR-486-3p might contribute to different HbF levels observed among thalassemic patients and, possibly, to the clinical severity of the disease. 相似文献
92.
Thorsten Klampfl Jelena D. Milosevic Ana Puda Andreas Sch?negger Klaudia Bagienski Tiina Berg Ashot S. Harutyunyan Bettina Gisslinger Elisa Rumi Luca Malcovati Daniela Pietra Chiara Elena Matteo Giovanni Della Porta Lisa Pieri Paola Guglielmelli Christoph Bock Michael Doubek Dana Dvorakova Nada Suvajdzic Dragica Tomin Natasa Tosic Zdenek Racil Michael Steurer Sonja Pavlovic Alessandro M. Vannucchi Mario Cazzola Heinz Gisslinger Robert Kralovics 《PloS one》2013,8(10)
Exome sequencing of primary tumors identifies complex somatic mutation patterns. Assignment of relevance of individual somatic mutations is difficult and poses the next challenge for interpretation of next generation sequencing data. Here we present an approach how exome sequencing in combination with SNP microarray data may identify targets of chromosomal aberrations in myeloid malignancies. The rationale of this approach is that hotspots of chromosomal aberrations might also harbor point mutations in the target genes of deletions, gains or uniparental disomies (UPDs). Chromosome 11 is a frequent target of lesions in myeloid malignancies. Therefore, we studied chromosome 11 in a total of 813 samples from 773 individual patients with different myeloid malignancies by SNP microarrays and complemented the data with exome sequencing in selected cases exhibiting chromosome 11 defects. We found gains, losses and UPDs of chromosome 11 in 52 of the 813 samples (6.4%). Chromosome 11q UPDs frequently associated with mutations of CBL. In one patient the 11qUPD amplified somatic mutations in both CBL and the DNA repair gene DDB1. A duplication within MLL exon 3 was detected in another patient with 11qUPD. We identified several common deleted regions (CDR) on chromosome 11. One of the CDRs associated with de novo acute myeloid leukemia (P=0.013). One patient with a deletion at the LMO2 locus harbored an additional point mutation on the other allele indicating that LMO2 might be a tumor suppressor frequently targeted by 11p deletions. Our chromosome-centered analysis indicates that chromosome 11 contains a number of tumor suppressor genes and that the role of this chromosome in myeloid malignancies is more complex than previously recognized. 相似文献
93.
Mattia Falconi Federico Iacovelli Alessandro Desideri 《Journal of molecular modeling》2013,19(9):3695-3704
Familial amyotrophic lateral sclerosis caused by mutations in copper-zinc superoxide dismutase (SOD1) is characterized by the presence of SOD1-rich inclusions in spinal cords. It has been shown that a reduced intra-subunit disulfide bridge apo-SOD1 can rapidly initiate fibrillation forming an inter-subunits disulfide under mild, physiologically accessible conditions. Once initiated, elongation can proceed via recruitment of either apo or partially metallated disulfide-intact SOD1 and the presence of copper, but not zinc, ions inhibit fibrillation. We propose a structural model, refined through molecular dynamics simulations, that, taking into account these experimental findings, provides a molecular explanation for the initiation and the elongation of SOD1 fibrils in physiological conditions. The model indicates the occurrence of a new dimeric unit, prone to interact one with the other due to the presence of a wide hydrophobic surface and specific electrostatic interactions. The model has dimensions consistent with the SOD1 fibril size observed through electron microscopy and provides a structural basis for the understanding of SOD1 fibrillation. Figure
ALS-linked superoxide dismutase fibrils 相似文献
94.
Massimo Collino Mara Rogazzo Alessandro Pini Elisa Benetti Arianna Carolina Rosa Fausto Chiazza Roberto Fantozzi Daniele Bani Emanuela Masini 《Journal of cellular and molecular medicine》2013,17(11):1494-1505
Although recent preclinical and clinical studies have demonstrated that recombinant human relaxin (rhRLX) may have important therapeutic potential in acute heart failure and chronic kidney diseases, the effects of acute rhRLX administration against renal ischaemia/reperfusion (I/R) injury have never been investigated. Using a rat model of 1‐hr bilateral renal artery occlusion followed by 6‐hr reperfusion, we investigated the effects of rhRLX (5 μg/Kg i.v.) given both at the beginning and after 3 hrs of reperfusion. Acute rhRLX administration attenuated the functional renal injury (increase in serum urea and creatinine), glomerular dysfunction (decrease in creatinine clearance) and tubular dysfunction (increase in urinary excretion of N‐acetyl‐β‐glucosaminidase) evoked by renal I/R. These beneficial effects were accompanied by a significant reduction in local lipid peroxidation, free radical‐induced DNA damage and increase in the expression/activity of the endogenous antioxidant enzymes Mn‐ and CuZn‐superoxide dismutases (SOD). Furthermore, rhRLX administration attenuated the increase in leucocyte activation, as suggested by inhibition of myeloperoxidase activity, intercellular‐adhesion‐molecule‐1 expression, interleukin (IL)‐1β, IL‐18 and tumour necrosis factor‐α production as well as increase in IL‐10 production. Interestingly, the reduced oxidative stress status and neutrophil activation here reported were associated with rhRLX‐induced activation of endothelial nitric oxide synthase and up‐regulation of inducible nitric oxide synthase, possibly secondary to activation of Akt and the extracellular signal‐regulated protein kinase (ERK) 1/2, respectively. Thus, we report herein that rhRLX protects the kidney against I/R injury by a mechanism that involves changes in nitric oxide signalling pathway. 相似文献
95.
Mate limitation in populations of the endangered Convolvulus lineatus L.: A case for genetic rescue?
Regina Berjano Perrine Gauthier Alessandro Fisogni David Doblas Virginie Pons John D. Thompson 《Journal for Nature Conservation》2013,21(5):334-341
In self-incompatible clonal plants, the spread of individual plants can exacerbate mate limitation to the point that it becomes a serious constraint on long-term population persistence, especially in small, isolated populations. In such species, it may be necessary to introduce new genetic material from other populations to restore seed production, a strategy termed “genetic rescue”. In this study we assess the potential pertinence of such genetic rescue in the clonal perennial plant Convolvulus lineatus L., whose populations are often highly reduced in spatial extent and are currently being fragmented by land development projects in Mediterranean France. To do so, we quantify fruit production in a range of populations of different size over four years and perform a series of hand-pollination experiments in natural populations to assess whether fruit set is limited by mate availability. We found that C. lineatus is a self-incompatible species that shows extremely low values of fruit set in natural populations and that a principal cause of this low fruit set is a lack of compatible pollen. This may be primarily due to clonal spread that causes individual populations to be comprised of patches containing one or very few incompatibility types. In small populations fragmented by human activities and which show an absence of fruit production, we thus argue that genetic rescue represents a promising conservation management strategy to avoid inevitable long-term future population decline. We discuss how best to introduce new genetic material into the study populations. 相似文献
96.
Jorg J. A. Calis Matt Maybeno Jason A. Greenbaum Daniela Weiskopf Aruna D. De Silva Alessandro Sette Can Ke?mir Bjoern Peters 《PLoS computational biology》2013,9(10)
T-cells have to recognize peptides presented on MHC molecules to be activated and elicit their effector functions. Several studies demonstrate that some peptides are more immunogenic than others and therefore more likely to be T-cell epitopes. We set out to determine which properties cause such differences in immunogenicity. To this end, we collected and analyzed a large set of data describing the immunogenicity of peptides presented on various MHC-I molecules. Two main conclusions could be drawn from this analysis: First, in line with previous observations, we showed that positions P4–6 of a presented peptide are more important for immunogenicity. Second, some amino acids, especially those with large and aromatic side chains, are associated with immunogenicity. This information was combined into a simple model that was used to demonstrate that immunogenicity is, to a certain extent, predictable. This model (made available at http://tools.iedb.org/immunogenicity/) was validated with data from two independent epitope discovery studies. Interestingly, with this model we could show that T-cells are equipped to better recognize viral than human (self) peptides. After the past successful elucidation of different steps in the MHC-I presentation pathway, the identification of variables that influence immunogenicity will be an important next step in the investigation of T-cell epitopes and our understanding of cellular immune responses. 相似文献
97.
Ilda D'Annessa Cinzia Tesauro Zhenxing Wang Barbara Arnò Laura Zuccaro Paola Fiorani Alessandro Desideri 《Biochimica et Biophysica Acta - Proteins and Proteomics》2013,1834(12):2712-2721
Human topoisomerase 1B, the unique target of the natural anticancer compound camptothecin, catalyzes the unwinding of supercoiled DNA by introducing transient single strand nicks and providing covalent protein–DNA adducts. The functional properties and the drug reactivity of the single Arg634Ala mutant have been investigated in comparison to the wild type enzyme. The mutant is characterized by an identical relaxation and cleavage rate but it displays resistance to camptothecin as indicated by a viability assay of the yeast cells transformed with the mutated protein. The mutant also displays a very fast religation rate that is only partially reduced by the presence of the drug, suggesting that this is the main reason for its resistance. A comparative analysis of the structural–dynamical properties of the native and mutant proteins by molecular dynamics simulation indicates that mutation of Arg634 brings to a loss of motion correlation between the different domains and in particular between the linker and the C-terminal domain, containing the catalytic tyrosine residue. These results indicate that the loss of motion correlation and the drug resistance are two strongly correlated events. 相似文献
98.
Savino di Lernia Mary Anne Tafuri Marina Gallinaro Francesca Alhaique Marie Balasse Lucia Cavorsi Paul D. Fullagar Anna Maria Mercuri Andrea Monaco Alessandro Perego Andrea Zerboni 《PloS one》2013,8(2)
Cattle pastoralism is an important trait of African cultures. Ethnographic studies describe the central role played by domestic cattle within many societies, highlighting its social and ideological value well beyond its mere function as ‘walking larder’. Historical depth of this African legacy has been repeatedly assessed in an archaeological perspective, mostly emphasizing a continental vision. Nevertheless, in-depth site-specific studies, with a few exceptions, are lacking. Despite the long tradition of a multi-disciplinary approach to the analysis of pastoral systems in Africa, rarely do early and middle Holocene archaeological contexts feature in the same area the combination of settlement, ceremonial and rock art features so as to be multi-dimensionally explored: the Messak plateau in the Libyan central Sahara represents an outstanding exception. Known for its rich Pleistocene occupation and abundant Holocene rock art, the region, through our research, has also shown to preserve the material evidence of a complex ritual dated to the Middle Pastoral (6080–5120 BP or 5200–3800 BC). This was centred on the frequent deposition in stone monuments of disarticulated animal remains, mostly cattle. Animal burials are known also from other African contexts, but regional extent of the phenomenon, state of preservation of monuments, and associated rock art make the Messak case unique. GIS analysis, excavation data, radiocarbon dating, zooarchaeological and isotopic (Sr, C, O) analyses of animal remains, and botanical information are used to explore this highly formalized ritual and the lifeways of a pastoral community in the Holocene Sahara. 相似文献
99.
Giovanna Poce Robert H. Bates Salvatore Alfonso Martina Cocozza Giulio Cesare Porretta Lluís Ballell Joaquin Rullas Fátima Ortega Alessandro De Logu Emanuela Agus Valentina La Rosa Maria Rosalia Pasca Edda De Rossi Baojie Wae Scott G. Franzblau Fabrizio Manetti Maurizio Botta Mariangela Biava 《PloS one》2013,8(2)
1,5-Diphenyl pyrroles were previously identified as a class of compounds endowed with high in vitro efficacy against M. tuberculosis. To improve the physical chemical properties and drug-like parameters of this class of compounds, a medicinal chemistry effort was undertaken. By selecting the optimal substitution patterns for the phenyl rings at N1 and C5 and by replacing the thiomorpholine moiety with a morpholine one, a new series of compounds was produced. The replacement of the sulfur with oxygen gave compounds with lower lipophilicity and improved in
vitro microsomal stability. Moreover, since the parent compound of this family has been shown to target MmpL3, mycobacterial mutants resistant to two compounds have been isolated and characterized by sequencing the mmpL3 gene; all the mutants showed point mutations in this gene. The best compound identified to date was progressed to dose-response studies in an acute murine TB infection model. The resulting ED99 of 49 mg/Kg is within the range of commonly employed tuberculosis drugs, demonstrating the potential of this chemical series. The in vitro and in vivo target validation evidence presented here adds further weight to MmpL3 as a druggable target of interest for anti-tubercular drug discovery. 相似文献
100.
Paola Luciani Cristiana Deledda Susanna Benvenuti Roberta Squecco Ilaria Cellai Benedetta Fibbi Ilaria Maddalena Marone Corinna Giuliani Giulia Modi Fabio Francini Gabriella Barbara Vannelli Alessandro Peri 《PloS one》2013,8(8)
Exendin-4 is a molecule currently used, in its synthetic form exenatide, for the treatment of type 2 diabetes mellitus. Exendin-4 binds and activates the Glucagon-Like Peptide-1 Receptor (GLP-1R), thus inducing insulin release. More recently, additional biological properties have been associated to molecules that belong to the GLP-1 family. For instance, Peptide YY and Vasoactive Intestinal Peptide have been found to affect cell adhesion and migration and our previous data have shown a considerable actin cytoskeleton rearrangement after exendin-4 treatment. However, no data are currently available on the effects of exendin-4 on tumor cell motility. The aim of this study was to investigate the effects of this molecule on cell adhesion, differentiation and migration in two neuroblastoma cell lines, SH-SY5Y and SK-N-AS. We first demonstrated, by Extra Cellular Matrix cell adhesion arrays, that exendin-4 increased cell adhesion, in particular on a vitronectin substrate. Subsequently, we found that this molecule induced a more differentiated phenotype, as assessed by i) the evaluation of neurite-like protrusions in 3D cell cultures, ii) the analysis of the expression of neuronal markers and iii) electrophysiological studies. Furthermore, we demonstrated that exendin-4 reduced cell migration and counteracted anchorage-independent growth in neuroblastoma cells. Overall, these data indicate for the first time that exendin-4 may have anti-tumoral properties. 相似文献