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71.
72.
Makelele Isaac Ahanamungu Bauters Marijn Verheyen Kris Barthel Matti Six Johan Rütting Tobias Bodé Samuel Cizungu Ntaboba Landry Mujinya Bazirake Basile Boyemba Bosela Faustin Kimbesa Fabrice Ewango Corneille Boeckx Pascal 《Plant and Soil》2022,476(1-2):743-753
Plant and Soil - Many applied disciplines have recognized problems related to the practice of data analysis within their own communities. Some of them have even declared the existence of a... 相似文献
73.
Pehuén Pereyra Gerber Mercedes Cabrini Carolina Jancic Luciana Paoletti Claudia Banchio Catalina von Bilderling Lorena Sigaut Lía I. Pietrasanta Gabriel Duette Eric O. Freed Genevieve de Saint Basile Catarina Ferreira Moita Luis Ferreira Moita Sebastian Amigorena Philippe Benaroch Jorge Geffner Matías Ostrowski 《The Journal of cell biology》2015,209(3):435-452
During the late stages of the HIV-1 replication cycle, the viral polyprotein Pr55Gag is recruited to the plasma membrane (PM), where it binds phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2) and directs HIV-1 assembly. We show that Rab27a controls the trafficking of late endosomes carrying phosphatidylinositol 4-kinase type 2 α (PI4KIIα) toward the PM of CD4+ T cells. Hence, Rab27a promotes high levels of PM phosphatidylinositol 4-phosphate and the localized production of PI(4,5)P2, therefore controlling Pr55Gag membrane association. Rab27a also controls PI(4,5)P2 levels at the virus-containing compartments of macrophages. By screening Rab27a effectors, we identified that Slp2a, Slp3, and Slac2b are required for the association of Pr55Gag with the PM and that Slp2a cooperates with Rab27a in the recruitment of PI4KIIα to the PM. We conclude that by directing the trafficking of PI4KIIα-positive endosomes toward the PM, Rab27a controls PI(4,5)P2 production and, consequently, HIV-1 replication. 相似文献
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75.
Jasreen Kular Jennifer C. Tickner Nathan J. Pavlos Helena M. Viola Tamara Abel Bay Sie Lim Xiaohong Yang Honghui Chen Robert Cook Livia C. Hool Ming Hao Zheng Jiake Xu 《The Journal of biological chemistry》2015,290(3):1729-1742
The maintenance of bone homeostasis requires tight coupling between bone-forming osteoblasts and bone-resorbing osteoclasts. However, the precise molecular mechanism(s) underlying the differentiation and activities of these specialized cells are still largely unknown. Here, we identify choline kinase β (CHKB), a kinase involved in the biosynthesis of phosphatidylcholine, as a novel regulator of bone homeostasis. Choline kinase β mutant mice (flp/flp) exhibit a systemic low bone mass phenotype. Consistently, osteoclast numbers and activity are elevated in flp/flp mice. Interestingly, osteoclasts derived from flp/flp mice exhibit reduced sensitivity to excessive levels of extracellular calcium, which could account for the increased bone resorption. Conversely, supplementation of cytidine 5′-diphosphocholine in vivo and in vitro, a regimen that bypasses CHKB deficiency, restores osteoclast numbers to physiological levels. Finally, we demonstrate that, in addition to modulating osteoclast formation and function, loss of CHKB corresponds with a reduction in bone formation by osteoblasts. Taken together, these data posit CHKB as a new modulator of bone homeostasis. 相似文献
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Singh P Sachdeva S Raj R Kumar V Mahajan MP Nasser S Vivas L Gut J Rosenthal PJ Feng TS Chibale K 《Bioorganic & medicinal chemistry letters》2011,21(15):4561-4563
3-Azido-, 3-amino- and 3-(1,2,3-triazol-1-yl)-β-lactams were synthesized and evaluated for their antiplasmodial activity against four strains of Plasmodium falciparum and KB cells for their cytotoxicity profiles. The presence of a cyclohexyl substituent at N-1 and a phenyl group on the triazole ring markedly improved the activity profiles of triazole-tethered β-lactam exhibiting IC50 values of 1.13, 1.21 and 1.00 μM against 3D7, K1 and W2 strains respectively. 相似文献
78.
Colussi F Serpa V Delabona Pda S Manzine LR Voltatodio ML Alves R Mello BL Pereira N Farinas CS Golubev AM Santos MA Polikarpov I 《Journal of microbiology and biotechnology》2011,21(8):808-817
Because of its elevated cellulolytic activity, the filamentous fungus Trichoderma harzianum has a considerable potential in biomass hydrolysis applications. Trichoderma harzianum cellobiohydrolase I (ThCBHI), an exoglucanase, is an important enzyme in the process of cellulose degradation. Here, we report an easy single-step ion-exchange chromatographic method for purification of ThCBHI and its initial biophysical and biochemical characterization. The ThCBHI produced by induction with microcrystalline cellulose under submerged fermentation was purified on DEAE-Sephadex A-50 media and its identity was confirmed by mass spectrometry. The ThCBHI biochemical characterization showed that the protein has a molecular mass of 66 kDa and pI of 5.23. As confirmed by smallangle X-ray scattering (SAXS), both full-length ThCBHI and its catalytic core domain (CCD) obtained by digestion with papain are monomeric in solution. Secondary structure analysis of ThCBHI by circular dichroism revealed alpha- helices and beta-strands contents in the 28% and 38% range, respectively. The intrinsic fluorescence emission maximum of 337 nm was accounted for as different degrees of exposure of ThCBHI tryptophan residues to water. Moreover, ThCBHI displayed maximum activity at pH 5.0 and temperature of 50 degrees C with specific activities against Avicel and p-nitrophenyl-β-D-cellobioside of 1.25 U/mg and 1.53 U/mg, respectively. 相似文献
79.
Lefeber DJ de Brouwer AP Morava E Riemersma M Schuurs-Hoeijmakers JH Absmanner B Verrijp K van den Akker WM Huijben K Steenbergen G van Reeuwijk J Jozwiak A Zucker N Lorber A Lammens M Knopf C van Bokhoven H Grünewald S Lehle L Kapusta L Mandel H Wevers RA 《PLoS genetics》2011,7(12):e1002427
Genetic causes for autosomal recessive forms of dilated cardiomyopathy (DCM) are only rarely identified, although they are thought to contribute considerably to sudden cardiac death and heart failure, especially in young children. Here, we describe 11 young patients (5-13 years) with a predominant presentation of dilated cardiomyopathy (DCM). Metabolic investigations showed deficient protein N-glycosylation, leading to a diagnosis of Congenital Disorders of Glycosylation (CDG). Homozygosity mapping in the consanguineous families showed a locus with two known genes in the N-glycosylation pathway. In all individuals, pathogenic mutations were identified in DOLK, encoding the dolichol kinase responsible for formation of dolichol-phosphate. Enzyme analysis in patients' fibroblasts confirmed a dolichol kinase deficiency in all families. In comparison with the generally multisystem presentation in CDG, the nonsyndromic DCM in several individuals was remarkable. Investigation of other dolichol-phosphate dependent glycosylation pathways in biopsied heart tissue indicated reduced O-mannosylation of alpha-dystroglycan with concomitant functional loss of its laminin-binding capacity, which has been linked to DCM. We thus identified a combined deficiency of protein N-glycosylation and alpha-dystroglycan O-mannosylation in patients with nonsyndromic DCM due to autosomal recessive DOLK mutations. 相似文献
80.
Membrane trafficking is key for signal transduction, cargo transportation, and in the case of autophagy, delivering cytoplasmic substrates to the lysosome for degradation. Autophagy requires the formation of a unique double membrane vesicle, the autophagosome. However, the mechanism by which the autophagosome forms is unknown. Our recent study focused on the role of Barkor/Atg14(L) in targeting the autophagy-specific class III phosphatidylinositol-3-kinase (PtdIns3KC3) complex to the early autophagosome has implicated this complex in autophagosome formation. This study found that the BATS domain of Barkor targets the PtdIns3KC3 complex to early autophagic structures and senses highly curved membranes enriched in phosphatidylinositol-3-phosphate (PtdIns(3)P). Consequently, this study uncovered an exciting new role for the PtdIns3KC3 complex as a potential inducer of autophagosome formation. 相似文献