Mesoscopic model for DNA G-quadruplex unfolding

[EN] Genomes contain rare guanine-rich sequences capable of assembling into four-stranded helical structures, termed G-quadruplexes, with potential roles in gene regulation and chromosome stability. Their mechanical unfolding has only been reported to date by all-atom simulations, which cannot dissect the major physical interactions responsible for their cohesion. Here, we propose a mesoscopic model to describe both the mechanical and thermal stability of DNA G-quadruplexes, where each nucleotide of the structure, as well as each central cation located at the inner channel, is mapped onto a single bead. In this framework we are able to simulate loading rates similar to the experimental ones, which are not reachable in simulations with atomistic resolution. In this regard, we present single-molecule force-induced unfolding experiments by a high-resolution optical tweezers on a DNA telomeric sequence capable of adopting a G-quadruplex conformation. Fitting the parameters of the model to the experiments we find a correct prediction of the rupture-force kinetics and a good agreement with previous near equilibrium measurements. Since G-quadruplex unfolding dynamics is halfway in complexity between secondary nucleic acids and tertiary protein structures, our model entails a nanoscale paradigm for non-equilibrium processes in the cell.Work supported by the Spanish Ministry of Economy and Competitiveness (MINECO), grant No. FIS2014-55867, co-financed by FEDER funds. We also thank the support of the Aragon Government and Fondo Social Europeo to FENOL group. Work in J.R.A.-G. laboratory was supported by a grant from MINECO, No. MAT2015-71806-R).Bergues-Pupo, A.; Gutiérrez, I.; Arias-Gonzalez, JR.; Falo, F.; Fiasconaro, A. (2017). Mesoscopic model for DNA G-quadruplex unfolding. Scientific Reports. 7:1-13. https://doi.org/10.1038/s41598-017-10849-2S1137Arias-Gonzalez, J. R. Single-molecule portrait of DNA and RNA double helices. Integr. 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Investigation of the physical risk factor in wall plastering job using WERA method

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The pursuit of American dream in American soccer as reflected in the Christian pulisic biography

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Optimization of temperature level to enhance worker performance in automotive industry

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The optimization of environmental factors at manual assembly worstation by using taguchi method

The objective of this study was to determine the dominance effects of environmental factors such as Illuminance, humidity and WBGT on the operators’ productivity at Malaysian automotive industry. A case study was carried out at an automotive components assembly factory. The environmental factors examined were the Illuminance (lux), humidity and WBGT of the surrounding workstation area. Two sets of representative data including the illuminance, humidity and WBGT level and production rate were collected during the study. The production rate data were collected through observations and survey questionnaires while the illuminance level was measured using photometer model RS 180-7133, the humidity and WBGT level were measured by using quest temp thermal environment monitor. Taguchi Method was utilized to find the sequence of dominant factors that contributed to the productivity of operator at that specified production workstation. The study reveals that the dominant factor contributed to the productivity was illuminance, followed by humidity and WBGT

Assessment of thermal comfort and optimization of environmental factors at automotive industry

The objective of this study is to determine the dominance effects of environmental factors such as Illuminance (lux), relative humidity (%) and WBGT (°C) on the operators' productivity at Malaysian automotive industry. One automotive parts assembly factory had been chosen as a subject for the study. The subjects were workers at the assembly section of the factory. The environment examined was the Illuminance (lux), relative humidity (%) and WBGT (°C) of the surrounding workstation area. Two sets of representative data including the Illuminance, relative humidity (%) and WBGT (°C) level and production rate were collected during the study. All the data was measured using Babuc apparatus which is capable to measure simultaneously those mentioned environmental factors. The time series data of fluctuating level of environmental were plotted to identify the significant changes of factors. Then Taguchi Method is being utilized to find the sequence of dominance factors that contributed to the productivity of operator at the specified production workstation. From there, optimum level for the three factors will be determine for optimum productivity. Further multiple linear regressions were employed to obtain the equation model in order to represent the relationship of these environmental factors towards productivity. The Thermal Comfort assessments of this station which is the scale PMV is 2.1 and PPD is 19% are likely to be satisfied by the worker. The study reveals that the dominant factor contribute to the productivity at the body assembly production line is WBGT and Illuminance whereas the empirical finding is closely related to the perception study by survey questionnaire distribution