Spatial-proteomics reveals phospho-signaling dynamics at subcellular resolution

Dynamic change in subcellular localization of signaling proteins is a general concept that eukaryotic cells evolved for eliciting a coordinated response to stimuli. Mass spectrometry-based proteomics in combination with subcellular fractionation can provide comprehensive maps of spatio-temporal regulation of protein networks in cells, but involves laborious workflows that does not cover the phospho-proteome level. Here we present a high-throughput workflow based on sequential cell fractionation to profile the global proteome and phospho-proteome dynamics across six distinct subcellular fractions. We benchmark the workflow by studying spatio-temporal EGFR phospho-signaling dynamics in vitro in HeLa cells and in vivo in mouse tissues. Finally, we investigate the spatio-temporal stress signaling, revealing cellular relocation of ribosomal proteins in response to hypertonicity and muscle contraction. Proteomics data generated in this study can be explored through https://SpatialProteoDynamics.github.io

Nitric oxide is required for the insulin sensitizing effects of contraction in mouse skeletal muscle

The factors regulating the increase in skeletal muscle insulin sensitivity after exercise are unclear. We examined whether nitric oxide (NO) is required for the increase in insulin sensitivity after ex vivo contractions. Isolated C57BL/6J mouse EDL muscles were contracted for 10min or remained at rest (basal) with or without the NO synthase (NOS) inhibition (N-G-monomethyl-l-arginine; l-NMMA; 100m). Then, 3.5h post contraction/basal, muscles were exposed to saline or insulin (120Uml(-1)) with or without l-NMMA during the last 30min. l-NMMA had no effect on basal skeletal muscle glucose uptake. The increase in muscle glucose uptake with insulin (57%) was significantly (P<0.05) greater after prior contraction (140% increase). NOS inhibition during the contractions had no effect on this insulin-sensitizing effect of contraction, whereas NOS inhibition during insulin prevented the increase in skeletal muscle insulin sensitivity post-contraction. Soluble guanylate cyclase inhibition, protein kinase G (PKG) inhibition or cyclic nucleotide phosphodiesterase inhibition each had no effect on the insulin-sensitizing effect of prior contraction. In conclusion, NO is required for increases in insulin sensitivity several hours after contraction of mouse skeletal muscle via a cGMP/PKG independent pathway

ZAK beta is activated by cellular compression and mediates contraction-induced MAP kinase signaling in skeletal muscle

Mechanical inputs give rise to p38 and JNK activation, which mediate adaptive physiological responses in various tissues. In skeletal muscle, contraction-induced p38 and JNK signaling ensure adaptation to exercise, muscle repair, and hypertrophy. However, the mechanisms by which muscle fibers sense mechanical load to activate this signaling have remained elusive. Here, we show that the upstream MAP3K ZAK beta is activated by cellular compression induced by osmotic shock and cyclic compression in vitro, and muscle contraction in vivo. This function relies on ZAKO's ability to recognize stress fibers in cells and Z-discs in muscle fibers when mechanically perturbed. Consequently, ZAK-deficient mice present with skeletal muscle defects characterized by fibers with centralized nuclei and progressive adaptation towards a slower myosin profile. Our results highlight how cells in general respond to mechanical compressive load and how mechanical forces generated during muscle contraction are translated into MAP kinase signaling.Peer reviewe

Multi-objective optimization of methane production system from biomass through anaerobic digestion

This work addressed the multi-objective optimization of a biogas production system considering both environmental and economic criteria. A mixed integer non-linear programming (MINLP) model was established and solved with non-dominated sorting genetic algorithm II, from which the Pareto fronts, the optimal technology combinations and operation conditions were obtained and analyzed. It's found that the system is feasible in both environmental and economic considerations after optimization. The most expensive processing section is decarbonization; the most expensive equipment is anaerobic digester; the most power-consuming processing section is digestion, followed by decarbonization and waste management. The positive green degree value on the process is attributed to processing section of digestion and waste management. 3:1 chicken feces and corn straw, solar energy, pressure swing adsorption and 3:1 chicken feces and rice straw, solar energy, pressure swing adsorption are turned out to be two robust technology combinations under different prices of methane and electricity by sensitivity analysis. The optimization results provide support for optimal design and operation of biogas production system considering environmental and economic objectives

Multi-objective optimization of methane production system from biomass through anaerobic digestion

This work addressed the multi-objective optimization of a biogas production system considering both environmental and economic criteria. A mixed integer non-linear programming (MINLP) model was established and solved with non-dominated sorting genetic algorithm II, from which the Pareto fronts, the optimal technology combinations and operation conditions were obtained and analyzed. It&#39;s found that the system is feasible in both environmental and economic considerations after optimization. The most expensive processing section is decarbonization; the most expensive equipment is anaerobic digester; the most power-consuming processing section is digestion, followed by decarbonization and waste management. The positive green degree value on the process is attributed to processing section of digestion and waste management. 3:1 chicken feces and corn straw, solar energy, pressure swing adsorption and 3:1 chicken feces and rice straw, solar energy, pressure swing adsorption are turned out to be two robust technology combinations under different prices of methane and electricity by sensitivity analysis. The optimization results provide support for optimal design and operation of biogas production system considering environmental and economic objectives. (C) 2018 The Chemical Industry and Engineering Society of China, and Chemical Industry Press. All rights reserved.</p

Process simulation and evaluation for NH3/CO2 separation from melamine tail gas with protic ionic liquids

Melamine production is known to produce a tail gas with a significant amount of NH3 and CO2. The most common separation methods applied to melamine tail gas are water scrubbing and urea co-production technology. With good stability, non-volatility and tailored properties, ionic liquids (ILs) are regarded as vital potential solvents for gas separation. Therefore, two new process technologies, one is the ionic liquid-based process (IL-0), and the other is the enhanced ionic liquid process (IL-En) was employed and evaluated for energy and cost efficiency. The IL-En employs stripping on the treatment of melamine tail gas. The protic ionic liquid named 1-butyl imidazolium bis (trifluoromethylsulfonyl) imide ([Bim][NTf2]) was selected for the evaluation of the melamine tail gas cleaning process. Thermodynamic data were fitted to the NRTL equations. Three full process flowsheets were simulated in Aspen Plus V11 (TM). A basic and an enhanced ionic liquid process (IL-0 and IL-En), a conventional water scrubbing (WS) technology as a comparison, process sensitivity analysis and energy/economic evaluation were carried out. The results showed that the total separation cost of the IL-En can be reduced by 61% compared to that of the WS process. Moreover, the IL-based flowsheet is simpler than WS and avoids wastewater discharge