Chalcone synthases (CHS, EC 2.3.1.74) are key enzymes that catalyze the first committed step in flavonoid biosynthesis. In this study, we isolated a chalcone synthase, named NtCHS6, from Nicotiana tabacum. This synt...Chalcone synthases (CHS, EC 2.3.1.74) are key enzymes that catalyze the first committed step in flavonoid biosynthesis. In this study, we isolated a chalcone synthase, named NtCHS6, from Nicotiana tabacum. This synthase shared high homology with the NSCHSL (Y14507) gene and contained most of the conserved active sites that are in CHS proteins. The phylogenetic analysis suggested that NtCHS6 protein shared a large genetic distance with other Solanaceae CHS proteins and was the most closely-related to an uncharacterized CHS from Solanum lycopersicum. The expression analysis indicated that NtCHS6 was abundantly expressed in leaves, especially in mature leaves. By scrutinizing its upstream promoter sequences, multiple cis-regulatory elements involved in light and drought responsive were detected. Furthermore, NtCHS6 expression decreased significantly under dark treatment and increased significantly under drought stress suggested that NtCHS6 expression exhibited both light responsiveness and drought responsiveness, and important roles in ultraviolet protection and drought tolerance. Our results might play展开更多
Effects of cobalt ions (Co2+) on horizontal cells in low extracellular calcium were examined in isolated, superfused carp retinas. While 0.1mmol/L Co2+ completely suppressed both rod- and cone-driven horizontal cells ...Effects of cobalt ions (Co2+) on horizontal cells in low extracellular calcium were examined in isolated, superfused carp retinas. While 0.1mmol/L Co2+ completely suppressed both rod- and cone-driven horizontal cells in normal Ringer’s solution, it enhanced light responses of cone horizontal cells in low (0.1mmol/L) calcium. The enhancement of the cone horizontal cell response by Co2+ was not caused by changes in light responsiveness of cone photoreceptors. Moreover, application of 50μmol/L IBMX, an inhibitor of phosphodiester enzyme, reduced the suppressive effect of 0.1 mmol/L Co2+ in normal Ringer’s solution. In consequence, the above-described enhancement of the cone horizontal cell light responsiveness may be due to a depolarization of cones caused by low calcium, which increases the activity of voltage-dependent calcium channels at cone terminals.展开更多
Based on the reversible host-guest inclusion/exclusion of cyclodextrin-functionalized graphene oxide(GO-CD) and azobenzene-terminated polyhedral oligomeric silsesquioxane(Azo-POSS), a novel kind of light-responsive na...Based on the reversible host-guest inclusion/exclusion of cyclodextrin-functionalized graphene oxide(GO-CD) and azobenzene-terminated polyhedral oligomeric silsesquioxane(Azo-POSS), a novel kind of light-responsive nanocomposites GO-POSS was developed under mild condition. ~1H NMR, ET-IR,TG, TEM and UV-vis spectroscopy were conducted to characterize the chemical composition and photoresponsive performance of obtained GO-POSS nanocomposites. The results demonstrated that nanocagestructured POSS and nanosheet GO components in GO-POSS exhibited pronounced supra molecular assembly/disassembly behavior upon UV/vis irradiation. Moreover, GO-POSS nanocomposites showed good water dispersity and had remarkable impact on oxygen permeability of conventional PVA-coated films under varied light irradiation conditions, which would be valuable for developing smart gas barrier materials in packaging.展开更多
Insufficient intratumoral penetration greatly hurdles the anticancer performance of nanomedicine. To realize highly efficient tumor penetration in a precisely and spatiotemporally controlled manner, far-red light-resp...Insufficient intratumoral penetration greatly hurdles the anticancer performance of nanomedicine. To realize highly efficient tumor penetration in a precisely and spatiotemporally controlled manner, far-red light-responsive nanoclusters (NCs) capable of size shrinkage and charge conversion were developed and co-administered with iRGD to synergistically improve the intratumoral penetration and the anticancer efficacy. The NCs were constructed using the singlet oxygen-sensitive (SOS) polyethylene glycolpolyurethane-polyethylene glycol (PEG-(1O2)PU-PEG) triblock copolymer to encapsulate the doxorubicin (DOX)-loaded, chlorin e6 (Ce6)-conjugated polyamindoamine (PAMAM) dendrimer (DCD) via the double-emulsion method. Co-administration of iRGD notably increased the permeability of NCs within tumor vasculature and tumor tissues. In addition, upon far-red light irradiation (660 nm) of tumors at low optical density (10 mW/cm2), the generated 1O2 could disintegrate the NCs and release the DCD with positive surface charge and ultra-small size (~ 5 nm), which synergized with iRGD to enable deep intratumoral penetration. Consequently, the local 1O2 at lethal concentrations along with the released DOX efficiently and cooperatively eradicated tumor cells. This study provides a convenient approach to spatiotemporally promote the intratumoral penetration of nanomedicine and mediate programmed anticancer therapy.展开更多
基金supported by the Agricultural Science and Technology Innovation Program, China (ASTIP-TRIC01)
文摘Chalcone synthases (CHS, EC 2.3.1.74) are key enzymes that catalyze the first committed step in flavonoid biosynthesis. In this study, we isolated a chalcone synthase, named NtCHS6, from Nicotiana tabacum. This synthase shared high homology with the NSCHSL (Y14507) gene and contained most of the conserved active sites that are in CHS proteins. The phylogenetic analysis suggested that NtCHS6 protein shared a large genetic distance with other Solanaceae CHS proteins and was the most closely-related to an uncharacterized CHS from Solanum lycopersicum. The expression analysis indicated that NtCHS6 was abundantly expressed in leaves, especially in mature leaves. By scrutinizing its upstream promoter sequences, multiple cis-regulatory elements involved in light and drought responsive were detected. Furthermore, NtCHS6 expression decreased significantly under dark treatment and increased significantly under drought stress suggested that NtCHS6 expression exhibited both light responsiveness and drought responsiveness, and important roles in ultraviolet protection and drought tolerance. Our results might play
基金Project supported by the State Commission of Science and Technology of China, the National Natural Science Foundation of China,the National Eye Institute(USA) and the Human Frontier Science Program.
文摘Effects of cobalt ions (Co2+) on horizontal cells in low extracellular calcium were examined in isolated, superfused carp retinas. While 0.1mmol/L Co2+ completely suppressed both rod- and cone-driven horizontal cells in normal Ringer’s solution, it enhanced light responses of cone horizontal cells in low (0.1mmol/L) calcium. The enhancement of the cone horizontal cell response by Co2+ was not caused by changes in light responsiveness of cone photoreceptors. Moreover, application of 50μmol/L IBMX, an inhibitor of phosphodiester enzyme, reduced the suppressive effect of 0.1 mmol/L Co2+ in normal Ringer’s solution. In consequence, the above-described enhancement of the cone horizontal cell light responsiveness may be due to a depolarization of cones caused by low calcium, which increases the activity of voltage-dependent calcium channels at cone terminals.
基金the Natural Science Foundation of China (No.51503181)for financial support
文摘Based on the reversible host-guest inclusion/exclusion of cyclodextrin-functionalized graphene oxide(GO-CD) and azobenzene-terminated polyhedral oligomeric silsesquioxane(Azo-POSS), a novel kind of light-responsive nanocomposites GO-POSS was developed under mild condition. ~1H NMR, ET-IR,TG, TEM and UV-vis spectroscopy were conducted to characterize the chemical composition and photoresponsive performance of obtained GO-POSS nanocomposites. The results demonstrated that nanocagestructured POSS and nanosheet GO components in GO-POSS exhibited pronounced supra molecular assembly/disassembly behavior upon UV/vis irradiation. Moreover, GO-POSS nanocomposites showed good water dispersity and had remarkable impact on oxygen permeability of conventional PVA-coated films under varied light irradiation conditions, which would be valuable for developing smart gas barrier materials in packaging.
基金The research was financially supported by the National Natural Science Foundation of China(Nos.51873142,51722305,and 81903068)the Ministry of Science and Technology of China(No.2016YFA0201200)111 project,and the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD).
文摘Insufficient intratumoral penetration greatly hurdles the anticancer performance of nanomedicine. To realize highly efficient tumor penetration in a precisely and spatiotemporally controlled manner, far-red light-responsive nanoclusters (NCs) capable of size shrinkage and charge conversion were developed and co-administered with iRGD to synergistically improve the intratumoral penetration and the anticancer efficacy. The NCs were constructed using the singlet oxygen-sensitive (SOS) polyethylene glycolpolyurethane-polyethylene glycol (PEG-(1O2)PU-PEG) triblock copolymer to encapsulate the doxorubicin (DOX)-loaded, chlorin e6 (Ce6)-conjugated polyamindoamine (PAMAM) dendrimer (DCD) via the double-emulsion method. Co-administration of iRGD notably increased the permeability of NCs within tumor vasculature and tumor tissues. In addition, upon far-red light irradiation (660 nm) of tumors at low optical density (10 mW/cm2), the generated 1O2 could disintegrate the NCs and release the DCD with positive surface charge and ultra-small size (~ 5 nm), which synergized with iRGD to enable deep intratumoral penetration. Consequently, the local 1O2 at lethal concentrations along with the released DOX efficiently and cooperatively eradicated tumor cells. This study provides a convenient approach to spatiotemporally promote the intratumoral penetration of nanomedicine and mediate programmed anticancer therapy.