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921.
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Veronica Obregon-Perko Katherine M. Bricker Gloria Mensah Ferzan Uddin Mithra R. Kumar Emily J. Fray Robert F. Siliciano Nils Schoof Anna Horner Maud Mavigner Shan Liang Thomas Vanderford Julian Sass Cliburn Chan Stella J. Berendam Katharine J. Bar George M. Shaw Guido Silvestri Genevieve G. Fouda Sallie R. Permar Ann Chahroudi 《Journal of virology》2021,95(2)
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Gloria Alvarez-Llamas Tatiana Martín-Rojas Fernando de la Cuesta Enrique Calvo Felix Gil-Dones Veronica M. Dardé Luis F. Lopez-Almodovar Luis R. Padial Juan-Antonio Lopez Fernando Vivanco Maria G. Barderas 《Molecular & cellular proteomics : MCP》2013,12(9):2426-2439
One of the major challenges in cardiovascular medicine is to identify candidate biomarker proteins. Secretome analysis is particularly relevant in this search as it focuses on a subset of proteins released by a cell or tissue under certain conditions. The sample can be considered as a plasma subproteome and it provides a more direct approximation to the in vivo situation. Degenerative aortic stenosis is the most common worldwide cause of valve replacement. Using a proteomic analysis of the secretome from aortic stenosis valves we could identify candidate markers related to this pathology, which may facilitate early diagnosis and treatment. For this purpose, we have designed a method to validate the origin of secreted proteins, demonstrating their synthesis and release by the tissue and ruling out blood origin. The nLC-MS/MS analysis showed the labeling of 61 proteins, 82% of which incorporated the label in only one group. Western blot and selective reaction monitoring differential analysis, revealed a notable role of the extracellular matrix. Variation in particular proteins such as PEDF, cystatin and clusterin emphasizes the link between aortic stenosis and atherosclerosis. In particular, certain proteins variation in secretome levels correlates well, not only with label incorporation trend (only labeled in aortic stenosis group) but, more importantly, with alterations found in plasma from an independent cohort of samples, pointing to specific candidate markers to follow up in diagnosis, prognosis, and therapeutic intervention.Degenerative aortic stenosis (AS)1 is currently the most common cause of valve replacement in Western countries, and a significant increase in its prevalence is expected in the future because of increasing longevity (1). At the same time that our population age increases it can be expected that cardiac valve disease, and AS in particular, will increase in parallel. More and more, clinicians are seeing patients with symptomatic severe AS who are very advanced in age and have severe comorbidities or significant frailty, making operative intervention either impossible or of very high risk in the eyes of the cardiac surgeon. For this reason, the need of new diagnostic and prognostic methods, together with the urgent need of new drugs for therapy, has increased making a correct diagnosis in the early stages of the disease thereby reducing the cost burden to society. Several lines of evidence have demonstrated that degenerative AS is an active process in which inflammation plays a key role. As such, preventative approaches similar to those used in coronary artery disease (CAD) may be also applicable to AS (2, 3, 4, 5, 6). However, recent studies reported no reduction in later states of AS disease using statins, which significantly benefit patients with atherosclerosis (7, 8). Hence, further research is required to elucidate the pathogenic mechanism of this prevalent disease and to identify the similarities and differences in relation to atherosclerosis.Proteomics has emerged as a particularly suitable platform for the nonbiased analysis of proteins involved in the pathogenesis of various diseases, such as AS (9, 10). This type of approach provided the basis for the development of biomarkers to detect patients at risk of developing degenerative AS. Plasma and serum have been the main source used in proteomic studies to identify candidate protein biomarkers, followed by tissue and cell samples. However, the use of plasma and serum is hampered by their complex nature and by the large dynamic range of protein concentrations, which may favor the detection of abundant proteins at the expense of those present at lower concentrations (11, 12). As such, the aortic valve secretome has emerged as an attractive target to further understand the AS pathogenic process. Tissue secretomes provide a more accurate model of the in vivo situation and, by minimizing serum contaminants, they facilitate the detection of low abundance proteins secreted into the blood (13).In the present study, aortic valves from AS patients and nonaffected control subjects were cultured and the secretome analyzed by nLC-MS/MS. The addition of labeled amino acids to the culture media enabled the origin of the secreted proteins to be validated (truly secreted versus serum contaminants) and provided with information related to the dynamics of their synthesis and release from tissue. 相似文献
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Luis Tolentino‐Lopez Aldo Segura‐Cabrera Paola Reyes‐Loyola Mirko Zimic Miguel Quiliano Veronica Briz Angeles Muñoz‐Fernández Mario Rodríguez‐Pérez Ian Ilizaliturri‐Flores Jose Correa‐Basurto 《Biopolymers》2013,99(1):10-21
The recent occurrence of 2009 influenza A (H1N1) pandemic as well as others has raised concern of a far more dangerous outcome should this virus becomes resistant to current drug therapies. The number of clinical cases that are resistant to oseltamivir (Tamiflu®) is larger than the limited number of neuraminidase (NA) mutations (H275Y, N295S, and I223R) that have been identified at the active site and that are associated to oseltamivir resistance. In this study, we have performed a comparative analysis between a set of NAs that have the most representative mutations located outside the active site. The recently crystallized NA‐oseltamivir complex (PDB ID: 3NSS) was used as a wild‐type structure. After selecting the target NA sequences, their three‐dimensional (3D) structure was built using 3NSS as a template by homology modeling. The 3D NA models were refined by molecular dynamics (MD) simulations. The refined models were used to perform a docking study, using oseltamivir as a ligand. Furthermore, the docking results were refined by free‐energy analysis using the MM‐PBSA method. The analysis of the MD simulation results showed that the NA models reached convergence during the first 10 ns. Visual inspection and structural measures showed that the mutated NA active sites show structural variations. The docking and MM‐PBSA results from the complexes showed different binding modes and free energy values. These results suggest that distant mutations located outside the active site of NA affect its structure and could be considered to be a new source of resistance to oseltamivir, which agrees with reports in the clinical literature. © 2012 Wiley Periodicals, Inc. 相似文献
930.
Xie Xie Veronica Dubrovskaya Nancy Yacoub Joanna Walska Tara Gleason Katherine Reid Edward B. Dubrovsky 《Developmental biology》2013
Drosophila RNase ZL (dRNaseZ) belongs to a family of endoribonucleases with a major role in tRNA 3′-end processing. The biochemical function of RNase ZL is conserved from yeast to human. Here we present a study of its biological function during Drosophila development. In flies, dRNaseZ provides a non-redundant function, as the RNZED24 knockout (KO) mutation causes early larval lethality. Mosaic and conditional rescue techniques were employed to determine dRNaseZ requirements at later stages. We found that dRNaseZ activity is essential for all phases of fly development that involve cell division, including growth of adult tissue progenitors during larval and metamorphic stages, and gametogenesis in adults. At the cellular level, two major phenotypes were identified—cell growth deficiency in endoreplicating tissues and cell cycle arrest in mitotic tissues. While cell growth and proliferation are both dependant on protein synthesis, the two phenotypes displayed reliance on different dRNaseZ functions. We found that dRNaseZ KO completely blocks tRNA maturation without diminishing the abundance of mature tRNA molecules. Our data indicate that growth arrest of endoreplicating cells is primarily attributed to the relocation of the pool of mature tRNAs into the nuclei causing a decrease in translation efficiency. Mitotically dividing cells appear to be less dependent on translation machinery as they maintain their normal size when deprived of dRNaseZ activity, but rather display a cell cycle arrest at the G2–M transition. 相似文献