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291.
292.
Ekaterina A. Ivanova Maria Giovanna De Leo Lambertus Van Den Heuvel Anna Pastore Henry Dijkman Maria Antonietta De Matteis Elena N. Levtchenko 《PloS one》2015,10(3)
Nephropathic cystinosis is a lysosomal storage disorder caused by mutations in the CTNS gene encoding cystine transporter cystinosin that results in accumulation of amino acid cystine in the lysosomes throughout the body and especially affects kidneys. Early manifestations of the disease include renal Fanconi syndrome, a generalized proximal tubular dysfunction. Current therapy of cystinosis is based on cystine-lowering drug cysteamine that postpones the disease progression but offers no cure for the Fanconi syndrome. We studied the mechanisms of impaired reabsorption in human proximal tubular epithelial cells (PTEC) deficient for cystinosin and investigated the endo-lysosomal compartments of cystinosin-deficient PTEC by means of light and electron microscopy. We demonstrate that cystinosin-deficient cells had abnormal shape and distribution of the endo-lysosomal compartments and impaired endocytosis, with decreased surface expression of multiligand receptors and delayed lysosomal cargo processing. Treatment with cysteamine improved surface expression and lysosomal cargo processing but did not lead to a complete restoration and had no effect on the abnormal morphology of endo-lysosomal compartments. The obtained results improve our understanding of the mechanism of proximal tubular dysfunction in cystinosis and indicate that impaired protein reabsorption can, at least partially, be explained by abnormal trafficking of endosomal vesicles. 相似文献
293.
Francesca Boldrin Stefano Casonato Elisa Dainese Claudia Sala Neeraj Dhar Giorgio Palù Giovanna Riccardi Stewart T. Cole Riccardo Manganelli 《Nucleic acids research》2010,38(12):e134
Tightly regulated gene expression systems represent invaluable tools for studying gene function and for the validation of drug targets in bacteria. While several regulated bacterial promoters have been characterized, few of them have been successfully used in mycobacteria. In this article we describe the development of a novel repressible promoter system effective in both fast- and slow-growing mycobacteria based on two chromosomally encoded repressors, dependent on tetracycline (TetR) and pristinamycin (Pip), respectively. This uniqueness results in high versatility and stringency. Using this method we were able to obtain an ftsZ conditional mutant in Mycobacterium smegmatis and a fadD32 conditional mutant in Mycobacterium tuberculosis, confirming their essentiality for bacterial growth in vitro. This repressible promoter system could also be exploited to regulate gene expression during M. tuberculosis intracellular growth. 相似文献
294.
295.
Fouani Malak Basset Charbel A. Jurjus Abdo R. Leone Lavinia Giovanna Tomasello Giovanni Leone Angelo 《Journal of molecular histology》2021,52(5):893-904
Journal of Molecular Histology - Salivary glands are considered the chief exocrine glands of the mouth and physiologically contribute to the maintenance of the homeostasis of the oral cavity. They... 相似文献
296.
Juan Carvajal-Quintero Lise Comte Xingli Giam Julian D. Olden Ulrich Brose Tibor Erős Ana Filipa Filipe Marie-Josée Fortin Katie Irving Claire Jacquet Stefano Larsen Albert Ruhi Sapna Sharma Fabricio Villalobos Pablo A. Tedesco 《Ecology letters》2023,26(2):291-301
Global ecosystems are facing a deepening biodiversity crisis, necessitating robust approaches to quantifying species extinction risk. The lower limit of the macroecological relationship between species range and body size has long been hypothesized as an estimate of the relationship between the minimum viable range size (MVRS) needed for species persistence and the organismal traits that affect space and resource requirements. Here, we perform the first explicit test of this assumption by confronting the MVRS predicted by the range-body size relationship with an independent estimate based on the scale of synchrony in abundance among spatially separated populations of riverine fish. We provide clear evidence of a positive relationship between the scale of synchrony and species body size, and strong support for the MVRS set by the lower limit of the range-body size macroecological relationship. This MVRS may help prioritize first evaluations for unassessed or data-deficient taxa in global conservation assessments. 相似文献
297.
Cristina Capanni Stefano Squarzoni Vittoria Cenni Maria Rosaria D’Apice Alessandra Gambineri Giuseppe Novelli Manfred Wehnert Renato Pasquali Nadir M. Maraldi Giovanna Lattanzi 《Cell cycle (Georgetown, Tex.)》2012,11(19):3568-3577
Prelamin A processing impairment is a common feature of a restricted group of rare genetic alterations/disorders associated with a wide range of clinical phenotypes. Changes in histone posttranslational modifications, alterations in non-histone chromatin proteins and chromatin disorganization have been specifically linked to impairment of specific, distinct prelamin A processing steps, but the molecular mechanism involved in these processes is not yet understood . In this study, we show that the accumulation of wild-type prelamin A detected in restrictive dermopathy (RD), as well as the accumulation of mutated forms of prelamin A identified in familial partial lipodystrophy (FPLD) and mandibuloacral dysplasia (MADA), affect the nuclear localization of barrier-to-autointegration factor (BAF), a protein able to link lamin A precursor to chromatin remodeling functions. Our findings, in accordance with previously described results, support the hypothesis of a prelamin A involvement in BAF nuclear recruitment and suggest BAF-prelamin A complex as a protein platform usually activated in prelamin A-accumulating diseases. Finally, we demonstrate the involvement of the inner nuclear membrane protein emerin in the proper localization of BAF-prelamin A complex. 相似文献
298.
Deregulation of cyclin E in human cells interferes with prereplication complex assembly 总被引:15,自引:0,他引:15
Ekholm-Reed S Méndez J Tedesco D Zetterberg A Stillman B Reed SI 《The Journal of cell biology》2004,165(6):789-800
Deregulation of cyclin E expression has been associated with a broad spectrum of human malignancies. Analysis of DNA replication in cells constitutively expressing cyclin E at levels similar to those observed in a subset of tumor-derived cell lines indicates that initiation of replication and possibly fork movement are severely impaired. Such cells show a specific defect in loading of initiator proteins Mcm4, Mcm7, and to a lesser degree, Mcm2 onto chromatin during telophase and early G1 when Mcm2-7 are normally recruited to license origins of replication. Because minichromosome maintenance complex proteins are thought to function as a heterohexamer, loading of Mcm2-, Mcm4-, and Mcm7-depleted complexes is likely to underlie the S phase defects observed in cyclin E-deregulated cells, consistent with a role for minichromosome maintenance complex proteins in initiation of replication and fork movement. Cyclin E-mediated impairment of DNA replication provides a potential mechanism for chromosome instability observed as a consequence of cyclin E deregulation. 相似文献
299.
Luca M Neri Roberta Bortul Giovanna Tabellini Paola Borgatti Giovanna Baldini Claudio Celeghini Silvano Capitani Alberto M Martelli 《Cellular signalling》2002,14(1):21-29
D-3 phosphorylated inositides are a peculiar class of lipids, synthesized by phosphatidylinositol 3-kinase (PtdIns 3-K), which are also present in the nucleus. In order to clarify a possible role for nuclear D-3 phosphorylated inositides during human erythroid differentiation, we have examined the issue of whether or not, in K562 human erythroleukemia cells, erythropoietin (EPO) may generate nuclear translocation of an active PtdIns 3-K. Immunoprecipitation with an anti-p85 regulatory subunit of PtdIns 3-K, revealed that both the intranuclear amount and the activity of the kinase increased rapidly and transiently in response to EPO. Enzyme translocation was blocked by the specific PtdIns 3-K pharmacological inhibitor, LY294002, which also inhibited erythroid differentiation. In vivo, intranuclear synthesis of phosphatidylinositol (3,4,5) trisphosphate (PtdIns (3,4,5)P(3)) was stimulated by EPO. Almost all PtdIns 3-K that translocated to the nucleus was highly phosphorylated on tyrosine residues of the p85 regulatory subunit. These findings strongly suggest that an important step in the signaling pathways that mediate EPO-induced erythroid differentiation may be represented by the intranuclear translocation of an active PtdIns 3-K. 相似文献
300.
Restaino Odile Francesca Borzacchiello Maria Giovanna Scognamiglio Ilaria Porzio Elena Manco Giuseppe Fedele Luigi Donatiello Cinzia De Rosa Mario Schiraldi Chiara 《Journal of industrial microbiology & biotechnology》2017,44(3):363-375
Journal of Industrial Microbiology & Biotechnology - Thermostable phosphotriesterase-like lactonases (PLLs) from extremophile archaea, like SsoPox from Sulfolobus solfataricus, are attractive... 相似文献