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排序方式: 共有542条查询结果,搜索用时 15 毫秒
1.
Janne Alahuhta Sarian Kosten Munemitsu Akasaka Dominique Auderset Mattia M. Azzella Rossano Bolpagni Claudia P. Bove Patricia A. Chambers Eglantine Chappuis John Clayton Mary de Winton Frauke Ecke Esperança Gacia Gana Gecheva Patrick Grillas Jennifer Hauxwell Seppo Hellsten Jan Hjort Mark V. Hoyer Christiane Ilg Agnieszka Kolada Minna Kuoppala Torben Lauridsen En Hua Li Balázs A. Lukács Marit Mjelde Alison Mikulyuk Roger P. Mormul Jun Nishihiro Beat Oertli Laila Rhazi Mouhssine Rhazi Laura Sass Christine Schranz Martin Søndergaard Takashi Yamanouchi Qing Yu Haijun Wang Nigel Willby Xiao Ke Zhang Jani Heino 《Journal of Biogeography》2017,44(8):1758-1769
2.
Mario Stampanoni Bassi Tommaso Nuzzo Luana Gilio Mattia Miroballo Alessia Casamassa Fabio Buttari Paolo Bellantonio Roberta Fantozzi Giovanni Galifi Roberto Furlan Annamaria Finardi Arianna De Rosa Anna Di Maio Francesco Errico Diego Centonze Alessandro Usiello 《Journal of neurochemistry》2021,159(5):857-866
3.
Emre Brookes Borries Demeler Camillo Rosano Mattia Rocco 《European biophysics journal : EBJ》2010,39(3):423-435
The interpretation of solution hydrodynamic data in terms of macromolecular structural parameters is not a straightforward
task. Over the years, several approaches have been developed to cope with this problem, the most widely used being bead modeling
in various flavors. We report here the implementation of the SOMO (SOlution MOdeller; Rai et al. in Structure 13:723–734,
2005) bead modeling suite within one of the most widely used analytical ultracentrifugation data analysis software packages, UltraScan
(Demeler in Modern analytical ultracentrifugation: techniques and methods, Royal Society of Chemistry, UK, 2005). The US-SOMO version is now under complete graphical interface control, and has been freed from several constraints present
in the original implementation. In the direct beads-per-atoms method, virtually any kind of residue as defined in the Protein
Data Bank (e.g., proteins, nucleic acids, carbohydrates, prosthetic groups, detergents, etc.) can be now represented with
beads whose number, size and position are all defined in user-editable tables. For large structures, a cubic grid method based
on the original AtoB program (Byron in Biophys J 72:408–415, 1997) can be applied either directly on the atomic structure, or on a previously generated bead model. The hydrodynamic parameters
are then computed in the rigid-body approximation. An extensive set of tests was conducted to further validate the method,
and the results are presented here. Owing to its accuracy, speed, and versatility, US-SOMO should allow to fully take advantage
of the potential of solution hydrodynamics as a complement to higher resolution techniques in biomacromolecular modeling. 相似文献
4.
Biosynthetic regulation of the human transferrin receptor by desferrioxamine in K562 cells 总被引:22,自引:0,他引:22
E Mattia K Rao D S Shapiro H H Sussman R D Klausner 《The Journal of biological chemistry》1984,259(5):2689-2692
Treatment of K562 cells with the iron chelator desferrioxamine results in the gradual increase in total cell receptors for transferrin. Receptor number rises 2.5-4.5-fold over 24 h and remains at the elevated level if the chelator is continuously present. Preincubation of the chelator with ferric chloride abolishes the effect. The drug has no effect on the 7-h half-life of the receptor. The increased number of receptors can be accounted for by a specific increase in the rate of receptor biosynthesis which reaches 3-4 times that seen in untreated cells by 6 h after the addition of the chelator. Isolation of mRNA from treated cells reveals that, after 8 h in the presence of desferrioxamine, there is a 3-fold increase in the specific translation of transferrin receptor over untreated cells. Total protein synthesis is not changed under these conditions. 相似文献
5.
Mattia Criscuoli Cristina Ulivieri Irene Filippi Sara Monaci Giuditta Guerrini Bianca Crifò Domiziana De Tommaso Giuliana Pelicci Cosima T. Baldari Cormac T. Taylor Fabio Carraro Antonella Naldini 《Journal of cellular physiology》2020,235(11):8058-8070
Hypoxia occurs in physiological and pathological conditions. T cells experience hypoxia in pathological and physiological conditions as well as in lymphoid organs. Indeed, hypoxia-inducible factor 1α (HIF-1α) affects T cell survival and functions. Rai, an Shc family protein member, exerts pro-survival effects in hypoxic neuroblastoma cells. Since Rai is also expressed in T cells, we here investigated its role in hypoxic T cells. In this work, hypoxia differently affected cell survival, proapoptotic, and metabolic programs in T cells, depending upon Rai expression. By using Jurkat cells stably expressing Rai and splenocytes from Rai−/−mice, we demonstrated that Rai promotes T cell survival and affects cell metabolism under hypoxia. Upon exposure to hypoxia, Jurkat T cells expressing Rai show (a) higher HIF-1α protein levels; (b) a decreased cell death and increased Akt/extracellular-signal-regulated kinase phosphorylation; (c) a decreased expression of proapoptotic markers, including caspase activities and poly(ADP-ribose) polymerase cleavage; (d) an increased glucose and lactate metabolism; (e) an increased activation of nuclear factor-kB pathway. The opposite effects were observed in hypoxic splenocytes from Rai−/−mice. Thus, Rai plays an important role in hypoxic signaling and may be relevant in the protection of T cells against hypoxia. 相似文献
6.
Manel Puig-Domingo Raúl M. Luque Jordi L. Reverter Laura M. López-Sánchez Manuel D. Gahete Michael D. Culler Gonzalo Díaz-Soto Francisco Lome?a Mattia Squarcia José Luis Mate Mireia Mora Laureano Fernández-Cruz Oscar Vidal Antonio Alastrué Jose Balibrea Irene Halperin Dídac Mauricio Justo P. Casta?o 《PloS one》2014,9(1)
Somatostatin receptors (ssts) are expressed in thyroid cancer cells, but their biological significance is not well understood. The aim of this study was to assess ssts in well differentiated (WDTC) and poorly differentiated thyroid cancer (PDTC) by means of imaging and molecular tools and its relationship with the efficacy of somatostatin analog treatment. Thirty-nine cases of thyroid carcinoma were evaluated (20 PDTC and 19 WDTC). Depreotide scintigraphy and mRNA levels of sst-subtypes, including the truncated variant sst5TMD4, were carried out. Depreotide scans were positive in the recurrent tumor in the neck in 6 of 11 (54%) PDTC, and in those with lung metastases in 5/11 cases (45.4%); sst5TMD4 was present in 18/20 (90%) of PDTC, being the most densely expressed sst-subtype, with a 20-fold increase in relation to sst2. In WDTC, sst2 was the most represented, while sst5TMD4 was not found; sst2 was significantly increased in PDTC in comparison to WDTC. Five depreotide positive PDTC received octreotide for 3–6 months in a pilot study with no changes in the size of the lesions in 3 of them, and a significant increase in the pulmonary and cervical lesions in the other 2. All PDTC patients treated with octreotide showed high expression of sst5TMD4. ROC curve analysis demonstrated that only sst5TMD4 discriminates between PDTC and WDTC. We conclude that sst5TMD4 is overexpressed in PDTC and may be involved in the lack of response to somatostatin analogue treatment. 相似文献
7.
Quantifying patterns of fine root dynamics is crucial to the understanding of ecosystem structure and function, and in predicting
how ecosystems respond to disturbance. Part of this understanding involves consideration of the carbon lost through root turnover.
In the context of the rainfall pattern in the tropics, it was hypothesised that rainfall would strongly influence fine root
biomass and longevity. A field study was conducted to determine root biomass, elemental composition and the influence of rainfall
on longevity of fine roots in a tropical lowland evergreen rainforest at Danum Valley, Sabah, Malaysia. A combination of root
coring, elemental analysis and rhizotron observation methods were used. Fine (less than 2 mm diameter) root biomass was relatively
low (1700 kg ha −1) compared with previously described rainforest data. Standing root biomass was positively correlated with
preceding rainfall, and the low fine root biomass in the dry season contained higher concentrations of N and lower concentrations
of P and K than at other times. Observations on rhizotrons demonstrated that the decrease in fine root biomass in the dry
season was a product of both a decrease in fine root length appearance and an increase in fine root length disappearance.
Fitting an overall model to root survival time showed significant effects of rainfall preceding root disappearance, with the
hazard of root disappearance decreasing by 8 for each 1 mm increase in the average daily (30 day) rainfall preceding root
disappearance. While it is acknowledged that other factors have a part to play, this work demonstrates the importance of rainfall
and soil moisture in influencing root biomass and root disappearance in this tropical rainforest. 相似文献
8.
Capsule Spontaneous calls and replies to playback of Scops Owls were significantly more frequent during the breeding period, when paired birds defend territories. The probability of spontaneous calls varied with moon phase, with a peak occurring during nights with a full moon. In some cases, during the winter, Scops Owls responded to playback calls of Little Owls, thus suggesting possible intra-guild competition between these species. 相似文献
9.
Blasco Morozzo Della Rocca Blasco Morozzo Della Rocca Daniela V. Miniero Gianluca Tasco Vincenza Dolce Mattia Falconi 《Molecular membrane biology》2013,30(5):443-452
The structural and dynamic properties of the oxoglutarate carrier were investigated by introducing a single tryptophan in the Trp-devoid carrier in position 184, 190 or 199 and by monitoring the fluorescence spectra in the presence and absence of the substrate oxoglutarate. In the absence of substrate, the emission maxima of Arg190Trp, Cys184Trp and Leu199Trp are centered at 342, 345 and 348 nm, respectively, indicating that these residues have an increasing degree of solvent exposure. The emission intensity of the Arg190Trp and Cys184Trp mutants is higher than that of Leu199Trp. Addition of substrate increases the emission intensity of Leu199Trp, but not that of Cys184Trp and Arg190Trp. A 3D model of the oxoglutarate carrier was built using the structure of the ADP/ATP carrier as a template and was validated with the experimental results available in the literature. The model identifies Lys122 as the most likely candidate for the quenching of Trp199. Consistently, the double mutant Lys122Ala-Leu199Trp exhibits a higher emission intensity than Leu199Trp and does not display further fluorescence enhancement in response to substrate addition. Substitution of Lys122 with Cys and evaluation of its reactivity with a sulphydryl reagent in the presence and absence of substrate confirms that residue 122 is masked by the substrate, likely through a substrate-induced conformational change. 相似文献
10.
Daniele Di Marino Tilmann Achsel Caroline Lacoux Mattia Falconi 《Journal of biomolecular structure & dynamics》2013,31(3):337-350
Mutations or deletions of FMRP, involved in the regulation of mRNA metabolism in brain, lead to the Fragile X syndrome (FXS), the most frequent form of inherited intellectual disability. A severe manifestation of the disease has been associated with the Ile304Asn mutation, located on the KH2 domain of the protein. Several hypotheses have been proposed to explain the possible molecular mechanism responsible for the drastic effect of this mutation in humans. Here, we performed a molecular dynamics simulation and show that the Ile304Asn mutation destabilizes the hydrophobic core producing a partial unfolding of two α-helices and a displacement of a third one. The affected regions show increased residue flexibility and motion. Molecular docking analysis revealed strongly reduced binding to a model single-stranded nucleic acid in agreement with known data that the two partially unfolded helices form the RNA-binding surface. The third helix, which we show here to be also affected, is involved in the PAK1 protein interaction. These two functional binding sites on the KH2 domain do not overlap spatially, and therefore, they can simultaneously bind their targets. Since the Ile304Asn mutation affects both binding sites, this may justify the severe clinical manifestation observed in the patient in which both mRNA metabolism activity and cytoskeleton remodeling would be affected. 相似文献