Objective:To study the transmembrane transport of chemical components of Chinese herbs and to explore the function of platycodin D (PD) on biomembranes.Methods:Interaction between PD and the dipalmitoylphosphatidylcho...Objective:To study the transmembrane transport of chemical components of Chinese herbs and to explore the function of platycodin D (PD) on biomembranes.Methods:Interaction between PD and the dipalmitoylphosphatidylcholine (DPPC) bilayer was reproduced by molecular dynamics simulation with the Martini force field.A model validation and methodological study were first performed,and were based on simulation investigations of transmembrane transport for three herbal compounds with distinct hydrophilic properties.Results:PD increased the mobility of the DPPC bilayer since its aglycone strongly interacted with the hydrophobic layer,which broke the structure of the gate layer,and weakened the ordered performance of hydrophobic tails.Conclusion:The Martini force field was successfully applied to the study of the interaction between herbal compounds and a biological membrane.By combining the dynamics equilibrium morphology,the distribution of drugs inside and outside the biomembrane,and the interaction sites of drugs on the DPPC bilayer,factors influencing transmembrane transport of drugs were elucidated and the function of platycodin D in a biological membrane was reproduced.展开更多
Botrytis cinerea is a typical necrotrophic pathogenic fungus that causes severe diseases in a wide range of plant species, leading to significant economic losses. Our previous study showed that BcSDR1 positively regul...Botrytis cinerea is a typical necrotrophic pathogenic fungus that causes severe diseases in a wide range of plant species, leading to significant economic losses. Our previous study showed that BcSDR1 positively regulates growth,development, and pathogenicity of B. cinerea. However, the regulation mechanism of BcSDR1 and the relationship between BcSDR1 and cAMP and MAPK signaling pathways are not well understood. In this study, transcriptome data showed that BcSDR1 is involved in glucose transmembrane transport, signal transduction, secondary metabolism, and other biological processes. BcSDR1 mutant(BCt41) showed remarkably weak sensitivity to cAMP and MAPK signaling pathways specific inhibitors, SQ22536 and U0126, and significantly decreased cAMP content. The key genes of cAMP and MAPK signaling pathways, BcGB1, BcBTP1, BcBOS1, BcRAS1, and BcBMP3 were significantly upregulated,whereas BcPLC1, BcBCG1, BcCDC4, BcSAK1, BcATF1, and BcBAP1 were significantly downregulated(P<0.05).BcSDR1 was obviously upregulated in BcBCG2, BcBCG3, BcPKA1, and BcPKAR RNA interference(RNAi) mutants, but significantly downregulated in BcPKA2, BcBMP1, and BcBMP3 RNAi mutants. Thus, BcBCG2, BcBCG3, BcPKA1, and BcPKAR negatively regulate BcSDR1 expression, whereas BcPKA2, BcBMP1, and BcBMP3 positively regulate BcSDR1expression.展开更多
纳米载体体内吸收过程复杂,受生物吸收屏障影响,纳米制剂在促进活性分子吸收利用度方面受到质疑。本实验采用大豆分离蛋白(soy protein isolate,SPI)制备包埋β-胡萝卜素的植物基纳米颗粒(β-carotene loaded soy protein isolate nanop...纳米载体体内吸收过程复杂,受生物吸收屏障影响,纳米制剂在促进活性分子吸收利用度方面受到质疑。本实验采用大豆分离蛋白(soy protein isolate,SPI)制备包埋β-胡萝卜素的植物基纳米颗粒(β-carotene loaded soy protein isolate nanoparticles,BC-SPIs),并通过体外模拟消化模型研究BC-SPIs在消化过程中的结构特性变化。同时,通过Caco2细胞转运模型考察消化条件对消化后BC-SPIs跨膜转运的影响机制。此外,利用含黏液层的Caco2-HT29共培养模型考察消化前后BC-SPIs的黏液层渗透性。研究发现,在消化前,BC-SPIs可以直接通过网格蛋白和小窝蛋白依赖的内吞作用被Caco2单层细胞吸收;而在经过体外模拟消化后,BC-SPIs粒径增大,可以通过网格蛋白依赖的内吞作用、小窝蛋白依赖的内吞作用以及巨胞饮3种内吞形式被细胞直接吸收。消化后的BC-SPIs带有更高的负电荷,跨越黏液层屏障的能力提高了0.48倍,同时β-胡萝卜素的跨膜转运量提高了0.56倍。本研究明确了BC-SPIs在消化前和消化后的不同吸收途径,揭示了BC-SPIs在模拟消化条件下与胆盐互作及尺寸增大对其细胞转运吸收效率的促进作用。这些发现可为进一步提高纳米载体在生物利用度方面的应用潜力提供理论参考,有助于推动纳米技术在药物、保健品等领域的发展。展开更多
In recent years,increasing research has been conducted on transmembrane transport processes and the mechanisms behind the microbial breakdown of polycyclic aromatic hydrocarbons(PAHs),including the role of membrane pr...In recent years,increasing research has been conducted on transmembrane transport processes and the mechanisms behind the microbial breakdown of polycyclic aromatic hydrocarbons(PAHs),including the role of membrane proteins in transmembrane transport and the mode of transmission.This article explains the adsorption,uptake and transmembrane transport of PAHs by bacteria,the regulation of membrane protein function during the transmembrane transport.There are three different regulation mechanisms for uptake,depending on the state and size of the oil droplets relative to the size of the microbial cells,which are(i)direct adhesion,(ii)emulsification and pseudosolubilization,and(iii)interfacial uptake.Furthermore,two main transmembrane transport modes are introduced,which are(i)active transport and(ii)passive uptake and active efflux mechanism.Meanwhile,introduce the proteomics and single cell analysis technology used to address these areas of research,such as Isobaric tags for relative and absolute quantitation(iTRAQ)technology and Nano Secondary ion mass spectrometry(Nano-SIMS).Additionally,analyze the changes in morphology and structure and the characteristics of microbial cell membranes in the process of transmembrane transport.Finally,recognize the microscopic mechanism of PAHs biodegradation in terms of cell and membrane proteins are of great theoretical and practical significance for understanding the factors that influence the efficient degradation of PAHs contaminants in soil and for remediating the PAHs contamination in this area with biotechnology.展开更多
OsNRT1.1a is a low-affinity nitrate（NO_3^-） transporter gene. In this study, another mRNA splicing product, OsNRT1.1b,putatively encoding a protein with six transmembrane domains, was identified based on the rice ge...OsNRT1.1a is a low-affinity nitrate（NO_3^-） transporter gene. In this study, another mRNA splicing product, OsNRT1.1b,putatively encoding a protein with six transmembrane domains, was identified based on the rice genomic database and bioinformatics analysis. OsNRT1.1a/OsNRT1.1b expression in Xenopus oocytes showed OsNRT1.1a-expressing oocytes accumulated ^（15）N levels to about half as compared to OsNRT1.1bexpressing oocytes. The electrophysiological recording of OsNRT1.1b-expressing oocytes treated with 0.25 mM NO_3^- confirmed ^（15）N accumulation data. More functional assays were performed to examine the function of OsNRT1.1b in rice. The expression of both OsNRT1.1a and OsNRT1.1b was abundant in roots and downregulated by nitrogen（N） deficiency. The shoot biomass of transgenic rice plants with OsNRT1.1a or OsNRT1.1b overexpression increased under various N supplies under hydroponic conditions compared to wild-type（WT）. The OsNRT1.1a overexpression lines showed increased plant N accumulation compared to the WT in 1.25 mM NH_4NO_3 and 2.5 mM NO_3^- or NH_4~＋ treatments, but not in 0.125 mM NH_4NO_3.However, OsNRT1.1b overexpression lines increased total N accumulation in all N treatments, including 0.125 m M NH_4NO_3,suggesting that under low N condition, OsNRT1.1b would accumulate more N in plants and improve rice growth, but also that OsNRT1.1a had no such function in rice plants.展开更多
Three methods,isotopic tracing,fluorescence quenching and electrophysiological technique, are normally used to study transmernbrane transport. Planar lipid bilayer system is an electrophysiological method,in which art...Three methods,isotopic tracing,fluorescence quenching and electrophysiological technique, are normally used to study transmernbrane transport. Planar lipid bilayer system is an electrophysiological method,in which artificial lipid and electrical measurement are used to simulate the ion-permeability of bio-membrane.It can展开更多
A new artificial transmembrane channel molecule bearing dihydrogen phosphate groups has been synthesized.The terminal dihydrogen phosphate groups enable the channel to be highly negatively charged at both ends of the ...A new artificial transmembrane channel molecule bearing dihydrogen phosphate groups has been synthesized.The terminal dihydrogen phosphate groups enable the channel to be highly negatively charged at both ends of the channel structures.The artificial channel could incorporate into the lipid bilayer efficiently under low concentration.The channel displays high NH4+/K+selectivity due to the electrostatic interaction and hydrogen bonding between NH4+and the terminal dihydrogen phosphate groups.展开更多
Oral administration is the best way for the most patients due to the good compliance,and intestinal epithelium is the main barrier of oral drug absorption.In order to overcome the small intestine epithelial barrier to...Oral administration is the best way for the most patients due to the good compliance,and intestinal epithelium is the main barrier of oral drug absorption.In order to overcome the small intestine epithelial barrier to orally deliver water-insoluble drugs,deoxycholic acid(DA),a substrate of the intestinal bile acid transporters,conjugated poly(2-ethyl-2-oxazoline)-poly(D,L-lactide)(DA-PEOz-PLA)was designed and synthesized,and deoxycholic acid-modified polymeric micelles composed of DA-PEOz-PLA and mPEG-PLA were fabricated to encapsulate model drug coumarin 6(C6)based on intestinal bile acid pathway.The structure of DA-PEOz-PLA was confirmed using 1 H NMR and TLC,and the molecular weight measured by GPC was 10034 g/mol with a PDI of 1.51.The C6-loaded polymeric micelles with drug loading content of 0.085%were characterized to have 40.11 nm in diameter and uniform spherical morphology observed by TEM.Furthermore,the deoxycholic acid-modified polymeric micelles were demonstrated to further enhance the transmembrane transport efficiency.The mechanic study evidenced that anchorage of deoxycholic acid onto the micelles surface enriched their transcellular transport pathway.Therefore,the designed deoxycholic acid-modified polymeric micelles might have a promising potential for oral delivery of water-insoluble drugs.展开更多
Transmembrane transport plays an important role in many physiological functions,and mimicking this biological process in artificial systems has potential applications in biosensing,drug delivery,and bionic science.Her...Transmembrane transport plays an important role in many physiological functions,and mimicking this biological process in artificial systems has potential applications in biosensing,drug delivery,and bionic science.Here,a lipophilic split aptamer was developed as a novel transmembrane carrier for adenosine triphosphate(ATP)transport.The ATP carrier comprises two split aptamer fragments and cholesterol tags,with the split aptamers acting as targetrecognition domains to enhance their specific binding capability and the cholesterol tags as hydrophobic domains to facilitate membrane penetration.Giant unilamellar vesicle experiments demonstrated that the ATP carrier-mediated transmembrane transport was concentration-and time-dependent and showed high transport selectivity.Moreover,the artificial carriers were applicable to living cells and facilitated rapid cell internalization of fluorescencelabeled ATP.Furthermore,carrier-mediated ATP transport into ATP-deficient cells enabled recovery of cellular ATP levels and improved cell viability.This study demonstrated the efficacy of an aptamer nanostructure for designing DNA-based synthetic carriers with high selectivity and flexibility.展开更多
基金The experiment was financially supported by the National Natural Science Foundation of China(81473364)Beijing Natural Science Foundation(7162122)Excellent Talents Training Subsidy Scheme of Beijing(2013D009999000003).
文摘Objective:To study the transmembrane transport of chemical components of Chinese herbs and to explore the function of platycodin D (PD) on biomembranes.Methods:Interaction between PD and the dipalmitoylphosphatidylcholine (DPPC) bilayer was reproduced by molecular dynamics simulation with the Martini force field.A model validation and methodological study were first performed,and were based on simulation investigations of transmembrane transport for three herbal compounds with distinct hydrophilic properties.Results:PD increased the mobility of the DPPC bilayer since its aglycone strongly interacted with the hydrophobic layer,which broke the structure of the gate layer,and weakened the ordered performance of hydrophobic tails.Conclusion:The Martini force field was successfully applied to the study of the interaction between herbal compounds and a biological membrane.By combining the dynamics equilibrium morphology,the distribution of drugs inside and outside the biomembrane,and the interaction sites of drugs on the DPPC bilayer,factors influencing transmembrane transport of drugs were elucidated and the function of platycodin D in a biological membrane was reproduced.
基金supported by the National Natural Science Foundation of China(31972217 and 32072369)the Central Government Guides Local Science and Technology Development Projects,China(206Z6501G and 216Z6502G)the Research Project of Basic Scientific Research Business Fees in Provincial Universities of Hebei Province,China(KY2021043 and KY2021044)。
文摘Botrytis cinerea is a typical necrotrophic pathogenic fungus that causes severe diseases in a wide range of plant species, leading to significant economic losses. Our previous study showed that BcSDR1 positively regulates growth,development, and pathogenicity of B. cinerea. However, the regulation mechanism of BcSDR1 and the relationship between BcSDR1 and cAMP and MAPK signaling pathways are not well understood. In this study, transcriptome data showed that BcSDR1 is involved in glucose transmembrane transport, signal transduction, secondary metabolism, and other biological processes. BcSDR1 mutant(BCt41) showed remarkably weak sensitivity to cAMP and MAPK signaling pathways specific inhibitors, SQ22536 and U0126, and significantly decreased cAMP content. The key genes of cAMP and MAPK signaling pathways, BcGB1, BcBTP1, BcBOS1, BcRAS1, and BcBMP3 were significantly upregulated,whereas BcPLC1, BcBCG1, BcCDC4, BcSAK1, BcATF1, and BcBAP1 were significantly downregulated(P<0.05).BcSDR1 was obviously upregulated in BcBCG2, BcBCG3, BcPKA1, and BcPKAR RNA interference(RNAi) mutants, but significantly downregulated in BcPKA2, BcBMP1, and BcBMP3 RNAi mutants. Thus, BcBCG2, BcBCG3, BcPKA1, and BcPKAR negatively regulate BcSDR1 expression, whereas BcPKA2, BcBMP1, and BcBMP3 positively regulate BcSDR1expression.
基金supported by the Construction Program of Hunan Innovative Province(China)-High-tech Industry Science and Technology Innovation Leading Project(No.2020SK2002)Changsha Municipal Natural Science Foundation,China(No.kq2014265)。
文摘纳米载体体内吸收过程复杂,受生物吸收屏障影响,纳米制剂在促进活性分子吸收利用度方面受到质疑。本实验采用大豆分离蛋白(soy protein isolate,SPI)制备包埋β-胡萝卜素的植物基纳米颗粒(β-carotene loaded soy protein isolate nanoparticles,BC-SPIs),并通过体外模拟消化模型研究BC-SPIs在消化过程中的结构特性变化。同时,通过Caco2细胞转运模型考察消化条件对消化后BC-SPIs跨膜转运的影响机制。此外,利用含黏液层的Caco2-HT29共培养模型考察消化前后BC-SPIs的黏液层渗透性。研究发现,在消化前,BC-SPIs可以直接通过网格蛋白和小窝蛋白依赖的内吞作用被Caco2单层细胞吸收;而在经过体外模拟消化后,BC-SPIs粒径增大,可以通过网格蛋白依赖的内吞作用、小窝蛋白依赖的内吞作用以及巨胞饮3种内吞形式被细胞直接吸收。消化后的BC-SPIs带有更高的负电荷,跨越黏液层屏障的能力提高了0.48倍,同时β-胡萝卜素的跨膜转运量提高了0.56倍。本研究明确了BC-SPIs在消化前和消化后的不同吸收途径,揭示了BC-SPIs在模拟消化条件下与胆盐互作及尺寸增大对其细胞转运吸收效率的促进作用。这些发现可为进一步提高纳米载体在生物利用度方面的应用潜力提供理论参考,有助于推动纳米技术在药物、保健品等领域的发展。
基金This work is sponsored by the National Natural Science Foundation of China(Grant No.41772234)the Natural Science Foundation of Guangxi(Grant No.2017GXNSFBA198168).
文摘In recent years,increasing research has been conducted on transmembrane transport processes and the mechanisms behind the microbial breakdown of polycyclic aromatic hydrocarbons(PAHs),including the role of membrane proteins in transmembrane transport and the mode of transmission.This article explains the adsorption,uptake and transmembrane transport of PAHs by bacteria,the regulation of membrane protein function during the transmembrane transport.There are three different regulation mechanisms for uptake,depending on the state and size of the oil droplets relative to the size of the microbial cells,which are(i)direct adhesion,(ii)emulsification and pseudosolubilization,and(iii)interfacial uptake.Furthermore,two main transmembrane transport modes are introduced,which are(i)active transport and(ii)passive uptake and active efflux mechanism.Meanwhile,introduce the proteomics and single cell analysis technology used to address these areas of research,such as Isobaric tags for relative and absolute quantitation(iTRAQ)technology and Nano Secondary ion mass spectrometry(Nano-SIMS).Additionally,analyze the changes in morphology and structure and the characteristics of microbial cell membranes in the process of transmembrane transport.Finally,recognize the microscopic mechanism of PAHs biodegradation in terms of cell and membrane proteins are of great theoretical and practical significance for understanding the factors that influence the efficient degradation of PAHs contaminants in soil and for remediating the PAHs contamination in this area with biotechnology.
基金supported by the National Natural Science Foundation of China (31172013, 31372122 and 31401938)
文摘OsNRT1.1a is a low-affinity nitrate（NO_3^-） transporter gene. In this study, another mRNA splicing product, OsNRT1.1b,putatively encoding a protein with six transmembrane domains, was identified based on the rice genomic database and bioinformatics analysis. OsNRT1.1a/OsNRT1.1b expression in Xenopus oocytes showed OsNRT1.1a-expressing oocytes accumulated ^（15）N levels to about half as compared to OsNRT1.1bexpressing oocytes. The electrophysiological recording of OsNRT1.1b-expressing oocytes treated with 0.25 mM NO_3^- confirmed ^（15）N accumulation data. More functional assays were performed to examine the function of OsNRT1.1b in rice. The expression of both OsNRT1.1a and OsNRT1.1b was abundant in roots and downregulated by nitrogen（N） deficiency. The shoot biomass of transgenic rice plants with OsNRT1.1a or OsNRT1.1b overexpression increased under various N supplies under hydroponic conditions compared to wild-type（WT）. The OsNRT1.1a overexpression lines showed increased plant N accumulation compared to the WT in 1.25 mM NH_4NO_3 and 2.5 mM NO_3^- or NH_4~＋ treatments, but not in 0.125 mM NH_4NO_3.However, OsNRT1.1b overexpression lines increased total N accumulation in all N treatments, including 0.125 m M NH_4NO_3,suggesting that under low N condition, OsNRT1.1b would accumulate more N in plants and improve rice growth, but also that OsNRT1.1a had no such function in rice plants.
文摘Three methods,isotopic tracing,fluorescence quenching and electrophysiological technique, are normally used to study transmernbrane transport. Planar lipid bilayer system is an electrophysiological method,in which artificial lipid and electrical measurement are used to simulate the ion-permeability of bio-membrane.It can
基金the National Natural Science Foundation of China (Nos.21725202,21572035)the National R&D Program of China (No.2017YFA0206901)STCSM (Nos.18XD1400800, 18JC1411600) for financial support
文摘A new artificial transmembrane channel molecule bearing dihydrogen phosphate groups has been synthesized.The terminal dihydrogen phosphate groups enable the channel to be highly negatively charged at both ends of the channel structures.The artificial channel could incorporate into the lipid bilayer efficiently under low concentration.The channel displays high NH4+/K+selectivity due to the electrostatic interaction and hydrogen bonding between NH4+and the terminal dihydrogen phosphate groups.
基金The National Natural Science Foundation of China(Grant No.81673366).
文摘Oral administration is the best way for the most patients due to the good compliance,and intestinal epithelium is the main barrier of oral drug absorption.In order to overcome the small intestine epithelial barrier to orally deliver water-insoluble drugs,deoxycholic acid(DA),a substrate of the intestinal bile acid transporters,conjugated poly(2-ethyl-2-oxazoline)-poly(D,L-lactide)(DA-PEOz-PLA)was designed and synthesized,and deoxycholic acid-modified polymeric micelles composed of DA-PEOz-PLA and mPEG-PLA were fabricated to encapsulate model drug coumarin 6(C6)based on intestinal bile acid pathway.The structure of DA-PEOz-PLA was confirmed using 1 H NMR and TLC,and the molecular weight measured by GPC was 10034 g/mol with a PDI of 1.51.The C6-loaded polymeric micelles with drug loading content of 0.085%were characterized to have 40.11 nm in diameter and uniform spherical morphology observed by TEM.Furthermore,the deoxycholic acid-modified polymeric micelles were demonstrated to further enhance the transmembrane transport efficiency.The mechanic study evidenced that anchorage of deoxycholic acid onto the micelles surface enriched their transcellular transport pathway.Therefore,the designed deoxycholic acid-modified polymeric micelles might have a promising potential for oral delivery of water-insoluble drugs.
基金The authors gratefully acknowledge the financial support of the Natural Science Foundation of China(nos.21735002,21575037,21778016,21675046,and 21877030).
文摘Transmembrane transport plays an important role in many physiological functions,and mimicking this biological process in artificial systems has potential applications in biosensing,drug delivery,and bionic science.Here,a lipophilic split aptamer was developed as a novel transmembrane carrier for adenosine triphosphate(ATP)transport.The ATP carrier comprises two split aptamer fragments and cholesterol tags,with the split aptamers acting as targetrecognition domains to enhance their specific binding capability and the cholesterol tags as hydrophobic domains to facilitate membrane penetration.Giant unilamellar vesicle experiments demonstrated that the ATP carrier-mediated transmembrane transport was concentration-and time-dependent and showed high transport selectivity.Moreover,the artificial carriers were applicable to living cells and facilitated rapid cell internalization of fluorescencelabeled ATP.Furthermore,carrier-mediated ATP transport into ATP-deficient cells enabled recovery of cellular ATP levels and improved cell viability.This study demonstrated the efficacy of an aptamer nanostructure for designing DNA-based synthetic carriers with high selectivity and flexibility.
