Manganese oxide(Mn_(3)O_(4))is of great potential for lithium storage based on conversion reactions,but its application in rechargeable lithium batteries is severely hindered by the low electric conductivity and large...Manganese oxide(Mn_(3)O_(4))is of great potential for lithium storage based on conversion reactions,but its application in rechargeable lithium batteries is severely hindered by the low electric conductivity and large volume variation during lithiation/delithiation.Herein,a biomimetic ear-of-wheat-like nanocomposite of ultrafine Mn_(3)O_(4)nanoparticles(MONPs)and multi-walled carbon nanotubes(MWCNTs)is prepared using a facile solvothermal method.The tightly packed MONP"cereal-grains"are directly grown and uniformly interspersed on the outer surface of skeleton MWCNT"central stems."The ultrafine MONPs are favorable to lithium incorporation/extraction while the interconnected MWCNT skeletons provide a highly conducting network for electron transportation.Consequently,a high reversible capacity of 810 m A h g^(-1)is obtained at the current density of 40 m A g^(-1).After 50 cycles at 160 m A g^(-1),the nanocomposite still delivers a capacity up to 796 m A h g^(-1),which is higher than twice of that of pure Mn_(3)O_(4)nanopowders.The unique nanostructure and the facile biomimetic method can be widely extended to design and explore various highperformance energy materials for lithium/sodium ion batteries and fuel cells.展开更多
Metastasis is a major cause of colorectal cancer(CRC)mortality,but its molecular mechanisms are still not fully understood.Here,we show that upregulated DDX39B correlates with liver metastases and aggressive phenotype...Metastasis is a major cause of colorectal cancer(CRC)mortality,but its molecular mechanisms are still not fully understood.Here,we show that upregulated DDX39B correlates with liver metastases and aggressive phenotypes in CRC.DDX39B is an independent prognostic factor associated with poor clinical outcome in CRC patients.We demonstrate that Sp1 potently activates DDX39B transcription by directly binding to the GC box of the DDX39B promoter in CRC cells.DDX39B overexpression augments the proliferation,migration,and invasion of CRC cells,while the opposite results are obtained in DDX39B-deficient CRC cells.Mechanistically,DDX39B interacts directly with and stabilizes PKM2 by competitively suppressing STUB1-mediated PKM2 ubiquitination and degradation.Importantly,DDX39B recruits importin a5 to accelerate the nuclear translocation of PKM2 independent of ERK1/2-mediated phosphorylation of PKM2,leading to the transactivation of oncogenes and glycolysis-related genes.Consequently,DDX39B enhances glucose uptake and lactate production to activate Warburg effect in CRC.We identify that Arg319 of DDX39B is required for PKM2 binding as well as PKM2 nuclear accumulation and for DDX39B to promote CRC growth and metastasis.In addition,blocking PKM2 nuclear translocation or treatment with glycolytic inhibitor 2-deoxy-D-glucose efficiently abolishes DDX39B-triggered malignant development in CRC.Taken together,ourfindings uncover akey role forDDX39B in modulating glycolytic reprogramming and aggressive progression,and implicate DDX39B as a potential therapeutic target in CRC.展开更多
Water uptake is crucial for crop growth and development and drought stress tolerance. The water channel aquaporins(AQP) play important roles in plant water uptake. Here, we discovered that a jasmonic acid analog, coro...Water uptake is crucial for crop growth and development and drought stress tolerance. The water channel aquaporins(AQP) play important roles in plant water uptake. Here, we discovered that a jasmonic acid analog, coronatine(COR), enhanced maize(Zea mays) root water uptake capacity under artificial water deficiency conditions. COR treatment induced the expression of the AQP gene Plasma membrane intrinsic protein 2;5(ZmPIP2;5).In vivo and in vitro experiments indicated that COR also directly acts on ZmPIP2;5 to improve water uptake in maize and Xenopus oocytes. The leaf water potential and hydraulic conductivity of roots growing under hyperosmotic conditions were higher in ZmPIP2;5-overexpression lines and lower in the zmpip2;5 knockout mutant, compared to wild-type plants. Based on a comparison between ZmPIP2;5 and other PIP2s, we predicted that COR may bind to the functional site in loop E of ZmPIP2;5. We confirmed this prediction by surface plasmon resonance technology and a microscale thermophoresis assay, and showed that deleting the binding motif greatly reduced COR binding. We identified the N241 residue as the COR-specific binding site, which may activate the channel of the AQP tetramer and increase water transport activity,which may facilitate water uptake under hyperosmotic stress.展开更多
基金financially supported by the National Natural Science Foundation of China(Grant No.51772240,51671154,21503158)the Key Research and Development Plan of Shaanxi Province(China,Grant No.2018ZDXM-GY-135)+1 种基金the National Key Research and Development Program of China(Grant No.2016YFB0700404)the Natural Science Foundation of Shaanxi Province(China,Grant No.2014JQ2-2007)
文摘Manganese oxide(Mn_(3)O_(4))is of great potential for lithium storage based on conversion reactions,but its application in rechargeable lithium batteries is severely hindered by the low electric conductivity and large volume variation during lithiation/delithiation.Herein,a biomimetic ear-of-wheat-like nanocomposite of ultrafine Mn_(3)O_(4)nanoparticles(MONPs)and multi-walled carbon nanotubes(MWCNTs)is prepared using a facile solvothermal method.The tightly packed MONP"cereal-grains"are directly grown and uniformly interspersed on the outer surface of skeleton MWCNT"central stems."The ultrafine MONPs are favorable to lithium incorporation/extraction while the interconnected MWCNT skeletons provide a highly conducting network for electron transportation.Consequently,a high reversible capacity of 810 m A h g^(-1)is obtained at the current density of 40 m A g^(-1).After 50 cycles at 160 m A g^(-1),the nanocomposite still delivers a capacity up to 796 m A h g^(-1),which is higher than twice of that of pure Mn_(3)O_(4)nanopowders.The unique nanostructure and the facile biomimetic method can be widely extended to design and explore various highperformance energy materials for lithium/sodium ion batteries and fuel cells.
基金This work was supported by the National Natural Science Foundation of China(81874071,81773756,82103525,and 82072933)1.3.5 project for disciplines of ecellence-Clinical Research Incubation Project,West China Hospital,Sichuan University(2020HXFH007)Post-Doctor Research Project,West China Hospital,Sichuan University(2020HXBH036).
文摘Metastasis is a major cause of colorectal cancer(CRC)mortality,but its molecular mechanisms are still not fully understood.Here,we show that upregulated DDX39B correlates with liver metastases and aggressive phenotypes in CRC.DDX39B is an independent prognostic factor associated with poor clinical outcome in CRC patients.We demonstrate that Sp1 potently activates DDX39B transcription by directly binding to the GC box of the DDX39B promoter in CRC cells.DDX39B overexpression augments the proliferation,migration,and invasion of CRC cells,while the opposite results are obtained in DDX39B-deficient CRC cells.Mechanistically,DDX39B interacts directly with and stabilizes PKM2 by competitively suppressing STUB1-mediated PKM2 ubiquitination and degradation.Importantly,DDX39B recruits importin a5 to accelerate the nuclear translocation of PKM2 independent of ERK1/2-mediated phosphorylation of PKM2,leading to the transactivation of oncogenes and glycolysis-related genes.Consequently,DDX39B enhances glucose uptake and lactate production to activate Warburg effect in CRC.We identify that Arg319 of DDX39B is required for PKM2 binding as well as PKM2 nuclear accumulation and for DDX39B to promote CRC growth and metastasis.In addition,blocking PKM2 nuclear translocation or treatment with glycolytic inhibitor 2-deoxy-D-glucose efficiently abolishes DDX39B-triggered malignant development in CRC.Taken together,ourfindings uncover akey role forDDX39B in modulating glycolytic reprogramming and aggressive progression,and implicate DDX39B as a potential therapeutic target in CRC.
基金supported by the National Key Research and Development Program of China (2016YFD0300102-4)。
文摘Water uptake is crucial for crop growth and development and drought stress tolerance. The water channel aquaporins(AQP) play important roles in plant water uptake. Here, we discovered that a jasmonic acid analog, coronatine(COR), enhanced maize(Zea mays) root water uptake capacity under artificial water deficiency conditions. COR treatment induced the expression of the AQP gene Plasma membrane intrinsic protein 2;5(ZmPIP2;5).In vivo and in vitro experiments indicated that COR also directly acts on ZmPIP2;5 to improve water uptake in maize and Xenopus oocytes. The leaf water potential and hydraulic conductivity of roots growing under hyperosmotic conditions were higher in ZmPIP2;5-overexpression lines and lower in the zmpip2;5 knockout mutant, compared to wild-type plants. Based on a comparison between ZmPIP2;5 and other PIP2s, we predicted that COR may bind to the functional site in loop E of ZmPIP2;5. We confirmed this prediction by surface plasmon resonance technology and a microscale thermophoresis assay, and showed that deleting the binding motif greatly reduced COR binding. We identified the N241 residue as the COR-specific binding site, which may activate the channel of the AQP tetramer and increase water transport activity,which may facilitate water uptake under hyperosmotic stress.
