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31.
Tina Wagner Lara Prez-Martínez Ren Schellhaas Marta Barrientos-Moreno Merve
ztürk Flix Prado Falk Butter Brian Luke 《PLoS genetics》2020,16(12)
Telomeres have the ability to adopt a lariat conformation and hence, engage in long and short distance intra-chromosome interactions. Budding yeast telomeres were proposed to fold back into subtelomeric regions, but a robust assay to quantitatively characterize this structure has been lacking. Therefore, it is not well understood how the interactions between telomeres and non-telomeric regions are established and regulated. We employ a telomere chromosome conformation capture (Telo-3C) approach to directly analyze telomere folding and its maintenance in S. cerevisiae. We identify the histone modifiers Sir2, Sin3 and Set2 as critical regulators for telomere folding, which suggests that a distinct telomeric chromatin environment is a major requirement for the folding of yeast telomeres. We demonstrate that telomeres are not folded when cells enter replicative senescence, which occurs independently of short telomere length. Indeed, Sir2, Sin3 and Set2 protein levels are decreased during senescence and their absence may thereby prevent telomere folding. Additionally, we show that the homologous recombination machinery, including the Rad51 and Rad52 proteins, as well as the checkpoint component Rad53 are essential for establishing the telomere fold-back structure. This study outlines a method to interrogate telomere-subtelomere interactions at a single unmodified yeast telomere. Using this method, we provide insights into how the spatial arrangement of the chromosome end structure is established and demonstrate that telomere folding is compromised throughout replicative senescence. 相似文献
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Prado Valentina Cinelli Marco Ter Haar Sterre F. Ravikumar Dwarakanath Heijungs Reinout Guinée Jeroen Seager Thomas P. 《The International Journal of Life Cycle Assessment》2020,25(12):2393-2406
The International Journal of Life Cycle Assessment - Weighting in life cycle assessment (LCA) incorporates stakeholder preferences in the decision-making process of comparative LCAs. Research... 相似文献
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Michele Preti Alan Lee Knight María Valentina Mujica Esteban Basoalto Sebastian Larsson Herrera Marco Tasin Sergio Angeli 《Journal of Applied Entomology》2021,145(8):822-830
Nineteen host plant volatiles (HPVs) were screened for attractivity to adult codling moth Cydia pomonella (L.) as a fourth component of core blends (3K) including (E,Z)-2,4-ethyl decadienoate, (E)-4,8-dimethyl-1,3,7-nonatriene and acetic acid. Each new quaternary combination was compared with a previously reported attractive bisexual lure (4K), consisting of the 3K blend plus 6-ethenyl-2,2,6-trimethyloxan-3-ol (pyranoid linalool oxide, pyrLOX). All lure evaluations were conducted in apple, Malus domestica (Borkhausen). Several compounds were found to significantly lower total and/or female catches when added to the 3K blend, including (Z)-3-hexenol, (E)-2-hexanal and hexyl butanoate (female and total moths), and (Z)-3-hexenyl acetate and linalool (female moths). Other compounds when added to the 3K blend did not increase or decrease moth catches, including methyl salicylate, (E)-β-ocimene, limonene, β-caryophyllene, butyl hexanoate, farnesol, terpineol, terpinen-4-ol and α-pinene. A few added compounds significantly increased moth catches compared with the 3K blend, including β-pinene (male moths), (Z)-jasmone (male and total moths), (E)-β-farnesene and β-myrcene (female and total moths), and (E,E)-α-farnesene (male, female, and total moths). In addition, each of these five compounds when added to the 3K core blend performed similarly to the 4K lure (male, females, and total moths). Further studies should expand these results through tests of these and other new blends with a range of component ratios and total loading amounts. Field trials should also be replicated within all host crops of codling moth and across major geographical production regions. 相似文献
36.
Castellani Valentina Sanyé-Mengual Esther Sala Serenella 《The International Journal of Life Cycle Assessment》2021,26(10):2040-2055
The International Journal of Life Cycle Assessment - Current patterns of household goods consumption generate relevant environmental pressures and impacts. Environmental impacts are not only... 相似文献
37.
Chunmei Li Eliane Beauregard-Lacroix Christine Kondratev Justine Rousseau Ah Jung Heo Katherine Neas Brett H. Graham Jill A. Rosenfeld Carlos A. Bacino Matias Wagner Maren Wenzel Fuad Al Mutairi Hamad Al Deiab Joseph G. Gleeson Valentina Stanley Maha S. Zaki Yong Tae Kwon Michel R. Leroux Philippe M. Campeau 《American journal of human genetics》2021,108(1):134-147
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Valentina A. Spiteri James Doutch Robert P. Rambo Jayesh Gor Paul A. Dalby Stephen J. Perkins 《Biophysical journal》2021,120(9):1814-1834
The human immunoglobulin G (IgG) class is the most prevalent antibody in serum, with the IgG1 subclass being the most abundant. IgG1 is composed of two Fab regions connected to a Fc region through a 15-residue hinge peptide. Two glycan chains are conserved in the Fc region in IgG; however, their importance for the structure of intact IgG1 has remained unclear. Here, we subjected glycosylated and deglycosylated monoclonal human IgG1 (designated as A33) to a comparative multidisciplinary structural study of both forms. After deglycosylation using peptide:N-glycosidase F, analytical ultracentrifugation showed that IgG1 remained monomeric and the sedimentation coefficients s020,w of IgG1 decreased from 6.45 S by 0.16–0.27 S. This change was attributed to the reduction in mass after glycan removal. X-ray and neutron scattering revealed changes in the Guinier structural parameters after deglycosylation. Although the radius of gyration (RG) was unchanged, the cross-sectional radius of gyration (RXS-1) increased by 0.1 nm, and the commonly occurring distance peak M2 of the distance distribution curve P(r) increased by 0.4 nm. These changes revealed that the Fab-Fc separation in IgG1 was perturbed after deglycosylation. To explain these changes, atomistic scattering modeling based on Monte Carlo simulations resulted in 123,284 and 119,191 trial structures for glycosylated and deglycosylated IgG1 respectively. From these, 100 x-ray and neutron best-fit models were determined. For these, principal component analyses identified five groups of structural conformations that were different for glycosylated and deglycosylated IgG1. The Fc region in glycosylated IgG1 showed a restricted range of conformations relative to the Fab regions, whereas the Fc region in deglycosylated IgG1 showed a broader conformational spectrum. These more variable Fc conformations account for the loss of binding to the Fcγ receptor in deglycosylated IgG1. 相似文献
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