Spectrin, the principal protein of the cytoskeleton of erythrocyte, plays a crucial role in the stability and flexibility of the plasma membrane of erythrocyte. In this work, we investigate the interactions between sp...Spectrin, the principal protein of the cytoskeleton of erythrocyte, plays a crucial role in the stability and flexibility of the plasma membrane of erythrocyte. In this work, we investigate the interactions between spectrins and phase-separated lipid bilayers using coarse-grained molecular dynamics simulation. We focus on the preference of spectrins with different lipids, the effects of the anionic lipids and the residue mutation on the interactions between spectrins and the lipid bilayers. The results indicate that spectrins prefer to contact with phosphatidylethanolamine(PE) lipids rather than with phosphatidylcholine(PC) lipids, and tend to contact with the liquid-disordered(Ld) domains enriched in unsaturated PE.Additionally, the anionic lipids, which show specific interaction with the positively charged or polar amino acids on the surface of the spectrins, can enhance the attraction between the spectrins and lipid domains. The mutation leads to the decrease of the structural stability of spectrins and increases the curvature of the lipid bilayer. This work provides some theoretical insights into understanding the erythrocyte structure and the mechanism of some blood diseases.展开更多
Sharp fluctuation of soybean prices in international and domestic markets has caused big risks for both domestic soybean producers and processing enterprises in recent years. It also increases the difficulties in impl...Sharp fluctuation of soybean prices in international and domestic markets has caused big risks for both domestic soybean producers and processing enterprises in recent years. It also increases the difficulties in implementing price stabilization policy for the government. This paper analyzes the volatility spillovers in soybean prices between international and domestic markets using the multivariate VAR-BEKK-GARCH model based on the data set from December 22,2004 to December 19,2014. The estimate results indicate that there are volatility spillover effects from domestic futures market to spot market and bilateral spillover between international futures market and domestic spot market. In order to prevent market manipulation and to reduce the impacts of price volatility in international soybean market on Chinese market,this paper proposes the following policy measures such as establishing early warning mechanism for soybean price fluctuations,improving soybean futures contract design and strengthening trading risk management mechanism,amplifying information disclosure system,and regularizing speculation activities of big traders.展开更多
基金supported by the National Natural Science Foundation of China (Grant No. 11674287)Zhejiang Provincial Natural Science Foundation of China(Grant No. LY19A040009)。
文摘Spectrin, the principal protein of the cytoskeleton of erythrocyte, plays a crucial role in the stability and flexibility of the plasma membrane of erythrocyte. In this work, we investigate the interactions between spectrins and phase-separated lipid bilayers using coarse-grained molecular dynamics simulation. We focus on the preference of spectrins with different lipids, the effects of the anionic lipids and the residue mutation on the interactions between spectrins and the lipid bilayers. The results indicate that spectrins prefer to contact with phosphatidylethanolamine(PE) lipids rather than with phosphatidylcholine(PC) lipids, and tend to contact with the liquid-disordered(Ld) domains enriched in unsaturated PE.Additionally, the anionic lipids, which show specific interaction with the positively charged or polar amino acids on the surface of the spectrins, can enhance the attraction between the spectrins and lipid domains. The mutation leads to the decrease of the structural stability of spectrins and increases the curvature of the lipid bilayer. This work provides some theoretical insights into understanding the erythrocyte structure and the mechanism of some blood diseases.
基金Supported by National Social Science Foundation of China(13BJY141)
文摘Sharp fluctuation of soybean prices in international and domestic markets has caused big risks for both domestic soybean producers and processing enterprises in recent years. It also increases the difficulties in implementing price stabilization policy for the government. This paper analyzes the volatility spillovers in soybean prices between international and domestic markets using the multivariate VAR-BEKK-GARCH model based on the data set from December 22,2004 to December 19,2014. The estimate results indicate that there are volatility spillover effects from domestic futures market to spot market and bilateral spillover between international futures market and domestic spot market. In order to prevent market manipulation and to reduce the impacts of price volatility in international soybean market on Chinese market,this paper proposes the following policy measures such as establishing early warning mechanism for soybean price fluctuations,improving soybean futures contract design and strengthening trading risk management mechanism,amplifying information disclosure system,and regularizing speculation activities of big traders.