Organic anion transporters(OATs)and organic anion transporter polypeptides(OATPs)are classified within two SLC superfamilies,namely,the SLC22A superfamily and the SLCO superfamily(formerly the SLC21A family),respectiv...Organic anion transporters(OATs)and organic anion transporter polypeptides(OATPs)are classified within two SLC superfamilies,namely,the SLC22A superfamily and the SLCO superfamily(formerly the SLC21A family),respectively.They are expressed in many tissues,such as the liver and kidney,and mediate the absorption and excretion of many endogenous and exogenous substances,including various drugs.Most are composed of 12 transmembrane polypeptide chains with the C-terminus and the N-terminus located in the cell cytoplasm.OATs and OATPs are abundantly expressed in the liver,where they mainly promote the uptake of various endogenous substrates such as bile acids and various exogenous drugs such as antifibrotic and anticancer drugs.However,differences in the locations of glycosylation sites,phosphorylation sites,and amino acids in the OAT and OATP structures lead to different substrates being transported to the liver,which ultimately results in their different roles in the liver.To date,few articles have addressed these aspects of OAT and OATP structures,and we study further the similarities and differences in their structures,tissue distribution,substrates,and roles in liver diseases.展开更多
GABA transporter 1(GAT1) takes important roles in multiple physiological processes through the uptake and release of GABA, but the regulation of GAT1 gene expression in different tissues is rarely known. To address th...GABA transporter 1(GAT1) takes important roles in multiple physiological processes through the uptake and release of GABA, but the regulation of GAT1 gene expression in different tissues is rarely known. To address the question, first, 5’ Rapid amplification of cDNA end (RACE) was used to determine GAT1 transcriptional starting sites in neonatal mouse cerebral cortex and intestine, adult mouse brain and adult rat testis. The products of 5’RACE were confirmed by DNA sequencing. We found that the transcript of GAT1 in neonatal mouse cerebral cortex and adult mouse brain starts at the same site (inside of exon 1), while in mouse intestine, GAT1 starts transcription in intron 1, and in rat testis, the transcript of GAT1 has an additional untranslation exon to the 5’ direction.展开更多
Metal–metal battery bears great potential for next-generation large-scale energy storage system because of its simple manufacture process and low production cost.However,the cross-over of metal cations from the catho...Metal–metal battery bears great potential for next-generation large-scale energy storage system because of its simple manufacture process and low production cost.However,the cross-over of metal cations from the cathode to the anode causes a loss in capacity and influences battery stability.Herein,a coating of poly(ionic liquid)(PIL)with poly(diallyldimethylammonium bis(trifluoromethanesulfonyl)imide)(PDADMA^(+)TFSI^(−))on a commercial polypropylene(PP)separator serves as an anion exchange membrane for a 3.3 V copper–lithium battery.The PIL has a positively charged polymer backbone that can block the migration of copper ions,thus improving Coulombic efficiency,long-term cycling stability and inhibiting self-discharge of the battery.It can also facilitate the conduction of anions through the membrane and reduce polarization,especially for fast charging/discharging.Bruce-Vincent method gives the transport number in the electrolyte to be 0.25 and 0.04 for PP separator without and with PIL coating,respectively.This suggests that the PIL layer reduces the contribution of the internal current due to cation transport.The use of PIL as a coating layer for commercial PP separator is a cost-effective way to improve overall electrochemical performance of copper–lithium batteries.Compared to PP and polyacrylic acid(PAA)/PP separators,the PIL/PP membrane raises the Coulombic efficiency to 99%and decreases the average discharge voltage drop to about 0.09 V when the current density is increased from 0.1 to 1 mA cm^(−2).展开更多
Sodium metal has shown great potential as an inexpensive anode for rechargeable batteries. However, the growth of sodium dendrites continues to hinder the commercialization of Na metal batteries. Herein, an effective ...Sodium metal has shown great potential as an inexpensive anode for rechargeable batteries. However, the growth of sodium dendrites continues to hinder the commercialization of Na metal batteries. Herein, an effective strategy using anion-anchoring halloysite nanotube(HNT) coating was proven to prevent the diffusion of anions and trigger uniform Na deposition. Through theoretical calculation, a model of active site of fixed anions exposed from HNTs after acid activation was established for the first time, revealing that Si–Al sites are effective active site of acid-activated HNTs. Furthermore, HNTs with strong and effective adsorption capacity for anions were obtained by controlling the structure of HNTs to regulate the exposure of Si–Al sites. The strong interaction between sites of acid-activated HNTs and the SO_(3)CF_(3)^(-) anion effectively promotes the dissociation of sodium salts, the release of Na^(+) and subsequent migration. As a result, HNTs acid activation for 4 h shows a steady sodium deposition process and displays high Coulombic efficiency in half cell, long cycle life in symmetric cell and full cell. This work provides a basic theoretical basis for the design of nanoclay with abundant and effective active site to fix anions for dendritic free metal batteries.展开更多
Plants absorb sunlight to power the photochem- ical reactions of photosynthesis, which can potentially damage the photosynthetic machinery. However, the mech- anism that protects chloroplasts from the damage remains u...Plants absorb sunlight to power the photochem- ical reactions of photosynthesis, which can potentially damage the photosynthetic machinery. However, the mech- anism that protects chloroplasts from the damage remains unclear. In this work, we demonstrated that rice (Oryza sativa L.) SLAC7 is a generally expressed membrane protein. Loss- of-function of SLAC7 caused continuous damage to the chloroplasts of mutant leaves under normal light conditions. Ion leakage indicators related to leaf damage such as H^O2 and abscisic acid levels were significantly higher in slac7-1 than in the wild type. Consistently, the photosynthesis efficiency and Fv/Fm ratio of slac7-1 were significantly decreased (similar to photoinhibition). In response to chloroplast damage, slat7- 1 altered its leaf morphology (curled or fused leaf) by the synergy between plant hormones and transcriptional factors to decrease the absorption of light, suggesting that a photoprotection mechanism for chloroplast damage was activated in slac7-1. When grown in dark conditions, slac7-1 displayed a normal phenotype. 5LAC7 under the control of the AtSLAC1 promoter could partially complement thephenotypes of Arabidopsis slacl mutants, indicating a partial conservation of SLAC protein functions. These results suggest that SLAC7 is essential for maintaining the chloroplast stability in rice.展开更多
The morphological and functional effects of titanium (Ti) citrate on human erythrocytes were studied by scanning electron microscope (SEM), sulphate uptake via band 3 protein and by determining the reduced and oxidise...The morphological and functional effects of titanium (Ti) citrate on human erythrocytes were studied by scanning electron microscope (SEM), sulphate uptake via band 3 protein and by determining the reduced and oxidised glutathione (GSH and GSSG, respectively) concentrations. The rate constant for sulphate uptake was significantly lower after Ti citrate treatment. Ti citrate (0.001 and 0.0025 mM) significantly decreased erythrocyte GSH and increased GSSG concentrations. At 0.005 mM Ti citrate, the intracellular GSH could not be tested due to significant cellular damage. SEM of erythrocytes treated with 0.001 mM and 0.0025 mM Ti citrate showed structural membrane defects but almost normal cellular diameters. At even higher Ti citrate concentrations (0.005 mM), erythrocytes showed obvious morphological alteration and shape changes compromising the cells physiological functions. In conclusion, although the Ti concentrations used in our experiments are physiologically high, the cumulative effect of prolonged exposure to much lower doses of Ti, as might occur during total hip replacement, should be considered for further experimental testing.展开更多
MOLECULAR PHYSIOLLGY OF HEPATOCELLULAR TRANSPORT PROTEINS Basolaferal transport systems Na+-dependent bile salt uptake Uptake of bile salts into the liver was first isolated perfused rat liver[1],isolated hepatocyte...MOLECULAR PHYSIOLLGY OF HEPATOCELLULAR TRANSPORT PROTEINS Basolaferal transport systems Na+-dependent bile salt uptake Uptake of bile salts into the liver was first isolated perfused rat liver[1],isolated hepatocyte cultures and basolateral plasma membrane vesicles [2,4].展开更多
Employing cathode materials with multiple redox couples and electrolytes with efficient cation transport kinetics are two effective approaches to improving the electrochemical performance of batteries.In this work,for...Employing cathode materials with multiple redox couples and electrolytes with efficient cation transport kinetics are two effective approaches to improving the electrochemical performance of batteries.In this work,for the first time,we present a design strategy of simultaneously realizing reversible cationic and anionic redox chemistries as well as selective anion/cation transport in the viologen-based COFs(BAVCOF:X,coordinated anions of X=Cl^(-),Br^(-),I^(-),and ClO_(4)^(-))for high-performance Na-ion cathodes.Besides the cationic redox of viologen segments,the different redox activities of anions effectively tune the total capacities of the COFs.Meanwhile,electrochemical analysis and ab-initial molecular dynamics(AIMD)calculation illustrate that the anion/cation transport kinetics of electrolytes caged in the COFs'channels can be selectively tuned by the coordinated anions.As a result,combining high-potential Br-/Br_(2)redox couple,cationic redox of viologen segments,and enhanced Na+transport kinetics,the BAV-COF:Brdemonstrates stable performance with energy densities of 358.7 and 145.2 Wh kg^(-1)at power densities of 116.5 and 2124.1 W kg^(-1),respectively.This study offers new insight into the fabrication of organic cathodes with anionic redox and the advantages of COFs electrode materials in anion/cation transport selectivity for energy storage applications.展开更多
胆红素作为人体的一种重要内源性物质,是临床诊断黄疸的主要依据,也是肝功能的重要指标。本文在简述胆红素代谢过程、代谢动力学及代谢异常的基础上,重点对有机阴离子转运多肽(organic anion transport polypeptide.OATP)和多药耐药相...胆红素作为人体的一种重要内源性物质,是临床诊断黄疸的主要依据,也是肝功能的重要指标。本文在简述胆红素代谢过程、代谢动力学及代谢异常的基础上,重点对有机阴离子转运多肽(organic anion transport polypeptide.OATP)和多药耐药相关蛋白(multidrug-associated protein.MRP)等转运体介导的胆红素转运、PXR和CAR等核受体对UGTlAl介导的胆红素代谢调控、药物对胆红素代谢的抑制和诱导,及其与胆红素相关病症关系等方面的最新进展进行归纳和总结,为进一步研究和揭示黄疸、高胆红素血症、新生儿黄疸等胆红素相关病症的发生原因和发生机制提供参考,并为其诊断、预防和治疗提供最新科学依据。展开更多
Organic anion transporter 3(OAT3)plays a vital role in removing a broad variety of anionic drugs from kidney,thus avoiding their possible toxicity in the body.In the current study,we investigated the role of insulin-l...Organic anion transporter 3(OAT3)plays a vital role in removing a broad variety of anionic drugs from kidney,thus avoiding their possible toxicity in the body.In the current study,we investigated the role of insulin-like growth factor 1(IGF-1)in the regulation of OAT3.We showed that IGF-1 induced a dose-and time-dependent increase in OAT3 transport activity,which correlated well with an increase in OAT3 expression.The IGF-1-induced increase in OAT3 expression was blocked by protein kinase A(PKA)inhibitor H89.Moreover,IGF-1 induced an increase in OAT3 phosphorylation,which was also blocked by H89.These data suggest that the IGF-1 modulation of OAT3 occurred through PKA signaling pathway.To further confirm the involvement of PKA,we treated OAT3-expressing cells with PKA activator Bt’2-cAMP,followed by examining OAT activity and phosphorylation.We showed that OAT3 activity and phosphorylation were much enhanced in Bt2-cAMP-treated cells as compared to that in control cells.Finally,linsitinib,an anticancer drug that blocks the IGF-1 receptor,abrogated IGF-1-stimulated OAT3 transport activity.In conclusion,our study demonstrated that IGF-1 regulates OAT3 expression and transport activity through PKA signaling pathway,possibly by phosphorylating the transporter.展开更多
文摘Organic anion transporters(OATs)and organic anion transporter polypeptides(OATPs)are classified within two SLC superfamilies,namely,the SLC22A superfamily and the SLCO superfamily(formerly the SLC21A family),respectively.They are expressed in many tissues,such as the liver and kidney,and mediate the absorption and excretion of many endogenous and exogenous substances,including various drugs.Most are composed of 12 transmembrane polypeptide chains with the C-terminus and the N-terminus located in the cell cytoplasm.OATs and OATPs are abundantly expressed in the liver,where they mainly promote the uptake of various endogenous substrates such as bile acids and various exogenous drugs such as antifibrotic and anticancer drugs.However,differences in the locations of glycosylation sites,phosphorylation sites,and amino acids in the OAT and OATP structures lead to different substrates being transported to the liver,which ultimately results in their different roles in the liver.To date,few articles have addressed these aspects of OAT and OATP structures,and we study further the similarities and differences in their structures,tissue distribution,substrates,and roles in liver diseases.
基金foundations from Chinese Academy of Sciences and Special Funds for Major State Basic reseaxch of China (G1999053903).
文摘GABA transporter 1(GAT1) takes important roles in multiple physiological processes through the uptake and release of GABA, but the regulation of GAT1 gene expression in different tissues is rarely known. To address the question, first, 5’ Rapid amplification of cDNA end (RACE) was used to determine GAT1 transcriptional starting sites in neonatal mouse cerebral cortex and intestine, adult mouse brain and adult rat testis. The products of 5’RACE were confirmed by DNA sequencing. We found that the transcript of GAT1 in neonatal mouse cerebral cortex and adult mouse brain starts at the same site (inside of exon 1), while in mouse intestine, GAT1 starts transcription in intron 1, and in rat testis, the transcript of GAT1 has an additional untranslation exon to the 5’ direction.
基金supported by grant from the Research Grants Council(City U 11305220)of the Hong Kong Special Administrative Region,China
文摘Metal–metal battery bears great potential for next-generation large-scale energy storage system because of its simple manufacture process and low production cost.However,the cross-over of metal cations from the cathode to the anode causes a loss in capacity and influences battery stability.Herein,a coating of poly(ionic liquid)(PIL)with poly(diallyldimethylammonium bis(trifluoromethanesulfonyl)imide)(PDADMA^(+)TFSI^(−))on a commercial polypropylene(PP)separator serves as an anion exchange membrane for a 3.3 V copper–lithium battery.The PIL has a positively charged polymer backbone that can block the migration of copper ions,thus improving Coulombic efficiency,long-term cycling stability and inhibiting self-discharge of the battery.It can also facilitate the conduction of anions through the membrane and reduce polarization,especially for fast charging/discharging.Bruce-Vincent method gives the transport number in the electrolyte to be 0.25 and 0.04 for PP separator without and with PIL coating,respectively.This suggests that the PIL layer reduces the contribution of the internal current due to cation transport.The use of PIL as a coating layer for commercial PP separator is a cost-effective way to improve overall electrochemical performance of copper–lithium batteries.Compared to PP and polyacrylic acid(PAA)/PP separators,the PIL/PP membrane raises the Coulombic efficiency to 99%and decreases the average discharge voltage drop to about 0.09 V when the current density is increased from 0.1 to 1 mA cm^(−2).
基金supported by the National Key R&D Program of China (2022YFE0201300)the China Postdoctoral Science Foundation (2022M712948)+2 种基金the CUG Scholar Scientific Research Funds at China University of Geosciences (Wuhan) (2019152)the Fundamental Research Funds for the Central Universities at China University of Geosciences (Wuhan)the National Science Fund for Distinguished Young Scholars (51225403)。
文摘Sodium metal has shown great potential as an inexpensive anode for rechargeable batteries. However, the growth of sodium dendrites continues to hinder the commercialization of Na metal batteries. Herein, an effective strategy using anion-anchoring halloysite nanotube(HNT) coating was proven to prevent the diffusion of anions and trigger uniform Na deposition. Through theoretical calculation, a model of active site of fixed anions exposed from HNTs after acid activation was established for the first time, revealing that Si–Al sites are effective active site of acid-activated HNTs. Furthermore, HNTs with strong and effective adsorption capacity for anions were obtained by controlling the structure of HNTs to regulate the exposure of Si–Al sites. The strong interaction between sites of acid-activated HNTs and the SO_(3)CF_(3)^(-) anion effectively promotes the dissociation of sodium salts, the release of Na^(+) and subsequent migration. As a result, HNTs acid activation for 4 h shows a steady sodium deposition process and displays high Coulombic efficiency in half cell, long cycle life in symmetric cell and full cell. This work provides a basic theoretical basis for the design of nanoclay with abundant and effective active site to fix anions for dendritic free metal batteries.
基金funded by the National High Technology Research and Development Program of China (863 Program)the National Program of Transgenic Variety Development of Chinathe National Natural Science Foundation of China
文摘Plants absorb sunlight to power the photochem- ical reactions of photosynthesis, which can potentially damage the photosynthetic machinery. However, the mech- anism that protects chloroplasts from the damage remains unclear. In this work, we demonstrated that rice (Oryza sativa L.) SLAC7 is a generally expressed membrane protein. Loss- of-function of SLAC7 caused continuous damage to the chloroplasts of mutant leaves under normal light conditions. Ion leakage indicators related to leaf damage such as H^O2 and abscisic acid levels were significantly higher in slac7-1 than in the wild type. Consistently, the photosynthesis efficiency and Fv/Fm ratio of slac7-1 were significantly decreased (similar to photoinhibition). In response to chloroplast damage, slat7- 1 altered its leaf morphology (curled or fused leaf) by the synergy between plant hormones and transcriptional factors to decrease the absorption of light, suggesting that a photoprotection mechanism for chloroplast damage was activated in slac7-1. When grown in dark conditions, slac7-1 displayed a normal phenotype. 5LAC7 under the control of the AtSLAC1 promoter could partially complement thephenotypes of Arabidopsis slacl mutants, indicating a partial conservation of SLAC protein functions. These results suggest that SLAC7 is essential for maintaining the chloroplast stability in rice.
文摘The morphological and functional effects of titanium (Ti) citrate on human erythrocytes were studied by scanning electron microscope (SEM), sulphate uptake via band 3 protein and by determining the reduced and oxidised glutathione (GSH and GSSG, respectively) concentrations. The rate constant for sulphate uptake was significantly lower after Ti citrate treatment. Ti citrate (0.001 and 0.0025 mM) significantly decreased erythrocyte GSH and increased GSSG concentrations. At 0.005 mM Ti citrate, the intracellular GSH could not be tested due to significant cellular damage. SEM of erythrocytes treated with 0.001 mM and 0.0025 mM Ti citrate showed structural membrane defects but almost normal cellular diameters. At even higher Ti citrate concentrations (0.005 mM), erythrocytes showed obvious morphological alteration and shape changes compromising the cells physiological functions. In conclusion, although the Ti concentrations used in our experiments are physiologically high, the cumulative effect of prolonged exposure to much lower doses of Ti, as might occur during total hip replacement, should be considered for further experimental testing.
基金supported by"H+Die Spitaler der Schweiz" the Swiss Agency for Development and Cooperation(DEZA)by the University Hospital Zurich/Switzerland
文摘MOLECULAR PHYSIOLLGY OF HEPATOCELLULAR TRANSPORT PROTEINS Basolaferal transport systems Na+-dependent bile salt uptake Uptake of bile salts into the liver was first isolated perfused rat liver[1],isolated hepatocyte cultures and basolateral plasma membrane vesicles [2,4].
基金supported by the NSFC/RGC Joint Research Scheme 2020/21(Project No:N_City U104/20)。
文摘Employing cathode materials with multiple redox couples and electrolytes with efficient cation transport kinetics are two effective approaches to improving the electrochemical performance of batteries.In this work,for the first time,we present a design strategy of simultaneously realizing reversible cationic and anionic redox chemistries as well as selective anion/cation transport in the viologen-based COFs(BAVCOF:X,coordinated anions of X=Cl^(-),Br^(-),I^(-),and ClO_(4)^(-))for high-performance Na-ion cathodes.Besides the cationic redox of viologen segments,the different redox activities of anions effectively tune the total capacities of the COFs.Meanwhile,electrochemical analysis and ab-initial molecular dynamics(AIMD)calculation illustrate that the anion/cation transport kinetics of electrolytes caged in the COFs'channels can be selectively tuned by the coordinated anions.As a result,combining high-potential Br-/Br_(2)redox couple,cationic redox of viologen segments,and enhanced Na+transport kinetics,the BAV-COF:Brdemonstrates stable performance with energy densities of 358.7 and 145.2 Wh kg^(-1)at power densities of 116.5 and 2124.1 W kg^(-1),respectively.This study offers new insight into the fabrication of organic cathodes with anionic redox and the advantages of COFs electrode materials in anion/cation transport selectivity for energy storage applications.
文摘胆红素作为人体的一种重要内源性物质,是临床诊断黄疸的主要依据,也是肝功能的重要指标。本文在简述胆红素代谢过程、代谢动力学及代谢异常的基础上,重点对有机阴离子转运多肽(organic anion transport polypeptide.OATP)和多药耐药相关蛋白(multidrug-associated protein.MRP)等转运体介导的胆红素转运、PXR和CAR等核受体对UGTlAl介导的胆红素代谢调控、药物对胆红素代谢的抑制和诱导,及其与胆红素相关病症关系等方面的最新进展进行归纳和总结,为进一步研究和揭示黄疸、高胆红素血症、新生儿黄疸等胆红素相关病症的发生原因和发生机制提供参考,并为其诊断、预防和治疗提供最新科学依据。
基金supported by grants(to Dr.Guofeng You)from National Institute of General Medical Sciences(R01-GM079123 and R01-GM097000,USA).
文摘Organic anion transporter 3(OAT3)plays a vital role in removing a broad variety of anionic drugs from kidney,thus avoiding their possible toxicity in the body.In the current study,we investigated the role of insulin-like growth factor 1(IGF-1)in the regulation of OAT3.We showed that IGF-1 induced a dose-and time-dependent increase in OAT3 transport activity,which correlated well with an increase in OAT3 expression.The IGF-1-induced increase in OAT3 expression was blocked by protein kinase A(PKA)inhibitor H89.Moreover,IGF-1 induced an increase in OAT3 phosphorylation,which was also blocked by H89.These data suggest that the IGF-1 modulation of OAT3 occurred through PKA signaling pathway.To further confirm the involvement of PKA,we treated OAT3-expressing cells with PKA activator Bt’2-cAMP,followed by examining OAT activity and phosphorylation.We showed that OAT3 activity and phosphorylation were much enhanced in Bt2-cAMP-treated cells as compared to that in control cells.Finally,linsitinib,an anticancer drug that blocks the IGF-1 receptor,abrogated IGF-1-stimulated OAT3 transport activity.In conclusion,our study demonstrated that IGF-1 regulates OAT3 expression and transport activity through PKA signaling pathway,possibly by phosphorylating the transporter.