RNA granules are cytoplasmic, microscopically visible, non-membrane ribo-nucleoprotein structures and are important posttranscriptional regulators in gene expression by controlling RNA translation and stability. TIA/G...RNA granules are cytoplasmic, microscopically visible, non-membrane ribo-nucleoprotein structures and are important posttranscriptional regulators in gene expression by controlling RNA translation and stability. TIA/G3BP/PABP-specific stress granules(SG) and GW182/DCP-specific RNA processing bodies(PB) are two major distinguishable RNA granules in somatic cells and contain various ribosomal subunits, translation factors, scaffold proteins, RNA-binding proteins, RNA decay enzymes and helicases to exclude m RNAs from the cellular active translational pool. Although SG formation is inducible due to cellular stress, PB exist physiologically in every cell. Both RNA granules are important components of the host antiviral defense. Virus infection imposes stress on host cells and thus induces SG formation. However, both RNA and DNA viruses must confront the hostile environment of host innate immunity and apply various strategies to block the formation of SG and PB for their effective infection and multiplication. This review summarizes the current research development in the field and the mechanisms of how individual viruses suppress the formation of host SG and PB for virus production.展开更多
In this paper the author first introduce a new concept of Lp-dual mixed volumes of star bodies which extends the classical dual mixed volumes. Moreover, we extend the notions of Lp- intersection body to Lp-mixed inter...In this paper the author first introduce a new concept of Lp-dual mixed volumes of star bodies which extends the classical dual mixed volumes. Moreover, we extend the notions of Lp- intersection body to Lp-mixed intersection body. Inequalities for Lp-dual mixed volumes of Lp-mixed intersection bodies are established and the results established here provide new estimates for these type of inequalities.展开更多
The human CCR4-NOT deadenylase complex consists of at least nine enzymatic and non-enzymatic subunits.Accumulating evidence suggests that the non-enzymatic subunits are involved in the regulation of mRNA deadenylation...The human CCR4-NOT deadenylase complex consists of at least nine enzymatic and non-enzymatic subunits.Accumulating evidence suggests that the non-enzymatic subunits are involved in the regulation of mRNA deadenylation,although their precise roles remain to be established.In this study,we addressed the function of the CNOT1 subunit by depleting its expression in HeLa cells.Flow cytometric analysis revealed that the sub G1 fraction was increased in CNOT1-depleted cells.Virtually,the same level of the sub G1 fraction was seen when cells were treated with a mixture of siRNAs targeted against all enzymatic subunits,suggesting that CNOT1 depletion induces apoptosis by destroying the CCR4-NOT-associated deadenylase activity.Further analysis revealed that CNOT1 depletion leads to a reduction in the amount of other CCR4-NOT subunits.Importantly,the specific activity of the CNOT6L immunoprecipitates-associated deadenylase from CNOT1-depleted cells was less than that from control cells.The formation of P-bodies,where mRNA decay is reported to take place,was largely suppressed in CNOT1-depleted cells.Therefore,CNOT1 has an important role in exhibiting enzymatic activity of the CCR4-NOT complex,and thus is critical in control of mRNA deadenylation and mRNA decay.We further showed that CNOT1 depletion enhanced CHOP mRNA levels and activated caspase-4,which is associated with endoplasmic reticulum ER stress-induced apoptosis.Taken together,CNOT1 depletion structurally and functionally deteriorates the CCR4-NOTcomplex and induces stabilization of mRNAs,which results in the increment of translation causing ER stress-mediated apoptosis.We conclude that CNOT1 contributes to cell viability by securing the activity of the CCR4-NOT deadenylase.展开更多
探索表达于大肠杆菌中的抗凝溶栓双功能水蛭素12肽和瑞替普酶融合蛋白(The fusion protein of 12 peptide of hirudin and reteplase,HV12p-rPA)的体外复性方法。采用直接透析复性和氧化复性结合透析复性两种方式,并分析复性时间、温度...探索表达于大肠杆菌中的抗凝溶栓双功能水蛭素12肽和瑞替普酶融合蛋白(The fusion protein of 12 peptide of hirudin and reteplase,HV12p-rPA)的体外复性方法。采用直接透析复性和氧化复性结合透析复性两种方式,并分析复性时间、温度、适宜的氧化-还原体系比例对复性率的影响。分别测定其体外抗凝活性和纤溶活性,确定复性效果。结果显示:将变性溶解的HV12p-rPA在含8mol/L脲,0.05mmol/LGSSG,0.7mol/LL-Arg的50mmol/LGly-NaOH(pH9.20)缓冲液中于25℃氧化复性6h后,再在含0.5mol/LL-Arg,1mmol/L胱氨酸,2mmol/L半胱氨酸的20mmol/LGly-NaOH(pH9.20)缓冲液中于4℃进行梯度脲浓度透析,每隔8h换液一次,透析48h,可获得具有抗凝活性为730ATU/mg,纤溶活性为19768IU/mg的可溶性蛋白质。展开更多
Background The release of Weibel-Palade Bodies (WPB) is a form of endothelial cell activation But the signal transduction pathway leading to WPB release is not yet defined We hypothesized that small G-protein ra...Background The release of Weibel-Palade Bodies (WPB) is a form of endothelial cell activation But the signal transduction pathway leading to WPB release is not yet defined We hypothesized that small G-protein rac1 and reactive oxygen species (ROS) mediate the ligand induced release of Weibel-Palade Bodies Methods We tested this hypothesis by using wild-type and mutant adenoviral rac1 expression vectors, and by manipulating the production and destruction of superoxide and hydrogen peroxide in human aortic endothelial cells (HAEC) KH*2/5DResults Thrombin (1 0 Unit, 30 min) induced the increase of WPB release by 3 7-fold in HAEC, and that H 2O 2 (0 1 mmol/L, 30 min) induced by 4 5-fold These results correlated with thrombin-stimulated activation of rac-GTP binding activity by 3 5-fold, and increase of ROS production by 3 4-fold The dominant negative adenoviral rac-N17 gene transfer dramatically inhibited the release of WPB by 64 2% (control) and 77 3% (thrombin-stimulation), and decreased ROS production by 65 5% (control) and 83 6% (thrombin-stimulation) compared with non-infected cells, respectively Anti-oxidants, catalase and N-acetyl-cysteine significantly decreased the release of WPB by 34% and 79% in control cells, and further decreased by 63 6% and 46 7% in rac-N17 transferred cells compared with non-infected cells We also confirmed that rac1 was located upstream of ROS in the WPB release pathway KH*2/5DConclusions Small G-protein rac1 medicates ligand-induced release of Weibel-Palade Bodies in human aortic endothelial cells, and the signal pathway of WPB release is a rac1-dependent ROS regulating mechanism展开更多
It is shown that a convex body has minimal dual p-surface area among its affine transformations of the same volume if and only if its dual p-surface area measure is isotropic. A double-sided estimate for the （n-1）-d...It is shown that a convex body has minimal dual p-surface area among its affine transformations of the same volume if and only if its dual p-surface area measure is isotropic. A double-sided estimate for the （n-1）-dimensional volume of the intersection of a dual p-surface isotropic convex body in terms of its affine invariant dual p-surface quantity is given. Furthermore, the dual p-isopermetric inequality is obtained.展开更多
The casepase is considered to regulate the process of programmed cell death in the development of organisms. In this study, caspase 3-like protease was detected by immunohistochemistry and immunoelectron microscopy du...The casepase is considered to regulate the process of programmed cell death in the development of organisms. In this study, caspase 3-like protease was detected by immunohistochemistry and immunoelectron microscopy during the development of sieve element and tracheary element of stem in Cucurbita moschata Duch. Antibody with brown color （under light microscopy） and gold particles （under transmission electron microscopy） for detecting caspase 3-like protease was mainly displayed in inner phloem, external phloem and xylem in the region close to procambium. From the results it was considered that caspase 3-like protease did exist in vascular elements and played different roles during the development of sieve and tracheary elements, and different types of programmed cell death might be carried out. The caspase 3-like protease mainly participated in making cytoplasmic streaming cease and in degrading P-protein bodies; however, it rarely participated in the function for signal transferring in the developmental sieve element. However, it might induce calcium accumulation for rupturing the tonoplast in the signal of PCD in the developmental tracheary element.展开更多
基金supported by grants from the China Natural Science Foundation (81825015 and 31630086)the Natural Science Foundation of Hubei Province Innovation Group (2017CFA022)Intramural Research Program of NCI/NIH (1ZIASC010357 to ZMZ)
文摘RNA granules are cytoplasmic, microscopically visible, non-membrane ribo-nucleoprotein structures and are important posttranscriptional regulators in gene expression by controlling RNA translation and stability. TIA/G3BP/PABP-specific stress granules(SG) and GW182/DCP-specific RNA processing bodies(PB) are two major distinguishable RNA granules in somatic cells and contain various ribosomal subunits, translation factors, scaffold proteins, RNA-binding proteins, RNA decay enzymes and helicases to exclude m RNAs from the cellular active translational pool. Although SG formation is inducible due to cellular stress, PB exist physiologically in every cell. Both RNA granules are important components of the host antiviral defense. Virus infection imposes stress on host cells and thus induces SG formation. However, both RNA and DNA viruses must confront the hostile environment of host innate immunity and apply various strategies to block the formation of SG and PB for their effective infection and multiplication. This review summarizes the current research development in the field and the mechanisms of how individual viruses suppress the formation of host SG and PB for virus production.
基金supported by the Natural Science Foundation of Zhejiang Province of China (Grant No. Y605065)the Foundation of the Education Department of Zhejiang Province of China (Grant No. 20050392)
文摘In this paper the author first introduce a new concept of Lp-dual mixed volumes of star bodies which extends the classical dual mixed volumes. Moreover, we extend the notions of Lp- intersection body to Lp-mixed intersection body. Inequalities for Lp-dual mixed volumes of Lp-mixed intersection bodies are established and the results established here provide new estimates for these type of inequalities.
基金supported by grants-in-aid from the Japan Society for the Promotion of Science and from the Ministry of Education,Culture,Sports,Science and Technology,Japan.
文摘The human CCR4-NOT deadenylase complex consists of at least nine enzymatic and non-enzymatic subunits.Accumulating evidence suggests that the non-enzymatic subunits are involved in the regulation of mRNA deadenylation,although their precise roles remain to be established.In this study,we addressed the function of the CNOT1 subunit by depleting its expression in HeLa cells.Flow cytometric analysis revealed that the sub G1 fraction was increased in CNOT1-depleted cells.Virtually,the same level of the sub G1 fraction was seen when cells were treated with a mixture of siRNAs targeted against all enzymatic subunits,suggesting that CNOT1 depletion induces apoptosis by destroying the CCR4-NOT-associated deadenylase activity.Further analysis revealed that CNOT1 depletion leads to a reduction in the amount of other CCR4-NOT subunits.Importantly,the specific activity of the CNOT6L immunoprecipitates-associated deadenylase from CNOT1-depleted cells was less than that from control cells.The formation of P-bodies,where mRNA decay is reported to take place,was largely suppressed in CNOT1-depleted cells.Therefore,CNOT1 has an important role in exhibiting enzymatic activity of the CCR4-NOT complex,and thus is critical in control of mRNA deadenylation and mRNA decay.We further showed that CNOT1 depletion enhanced CHOP mRNA levels and activated caspase-4,which is associated with endoplasmic reticulum ER stress-induced apoptosis.Taken together,CNOT1 depletion structurally and functionally deteriorates the CCR4-NOTcomplex and induces stabilization of mRNAs,which results in the increment of translation causing ER stress-mediated apoptosis.We conclude that CNOT1 contributes to cell viability by securing the activity of the CCR4-NOT deadenylase.
文摘探索表达于大肠杆菌中的抗凝溶栓双功能水蛭素12肽和瑞替普酶融合蛋白(The fusion protein of 12 peptide of hirudin and reteplase,HV12p-rPA)的体外复性方法。采用直接透析复性和氧化复性结合透析复性两种方式,并分析复性时间、温度、适宜的氧化-还原体系比例对复性率的影响。分别测定其体外抗凝活性和纤溶活性,确定复性效果。结果显示:将变性溶解的HV12p-rPA在含8mol/L脲,0.05mmol/LGSSG,0.7mol/LL-Arg的50mmol/LGly-NaOH(pH9.20)缓冲液中于25℃氧化复性6h后,再在含0.5mol/LL-Arg,1mmol/L胱氨酸,2mmol/L半胱氨酸的20mmol/LGly-NaOH(pH9.20)缓冲液中于4℃进行梯度脲浓度透析,每隔8h换液一次,透析48h,可获得具有抗凝活性为730ATU/mg,纤溶活性为19768IU/mg的可溶性蛋白质。
文摘Background The release of Weibel-Palade Bodies (WPB) is a form of endothelial cell activation But the signal transduction pathway leading to WPB release is not yet defined We hypothesized that small G-protein rac1 and reactive oxygen species (ROS) mediate the ligand induced release of Weibel-Palade Bodies Methods We tested this hypothesis by using wild-type and mutant adenoviral rac1 expression vectors, and by manipulating the production and destruction of superoxide and hydrogen peroxide in human aortic endothelial cells (HAEC) KH*2/5DResults Thrombin (1 0 Unit, 30 min) induced the increase of WPB release by 3 7-fold in HAEC, and that H 2O 2 (0 1 mmol/L, 30 min) induced by 4 5-fold These results correlated with thrombin-stimulated activation of rac-GTP binding activity by 3 5-fold, and increase of ROS production by 3 4-fold The dominant negative adenoviral rac-N17 gene transfer dramatically inhibited the release of WPB by 64 2% (control) and 77 3% (thrombin-stimulation), and decreased ROS production by 65 5% (control) and 83 6% (thrombin-stimulation) compared with non-infected cells, respectively Anti-oxidants, catalase and N-acetyl-cysteine significantly decreased the release of WPB by 34% and 79% in control cells, and further decreased by 63 6% and 46 7% in rac-N17 transferred cells compared with non-infected cells We also confirmed that rac1 was located upstream of ROS in the WPB release pathway KH*2/5DConclusions Small G-protein rac1 medicates ligand-induced release of Weibel-Palade Bodies in human aortic endothelial cells, and the signal pathway of WPB release is a rac1-dependent ROS regulating mechanism
基金Project supported by the National Natural Science Foundation of China (Grant No.10671117)
文摘It is shown that a convex body has minimal dual p-surface area among its affine transformations of the same volume if and only if its dual p-surface area measure is isotropic. A double-sided estimate for the （n-1）-dimensional volume of the intersection of a dual p-surface isotropic convex body in terms of its affine invariant dual p-surface quantity is given. Furthermore, the dual p-isopermetric inequality is obtained.
基金Supported by the National Natural Science Foundation of China (30470863).
文摘The casepase is considered to regulate the process of programmed cell death in the development of organisms. In this study, caspase 3-like protease was detected by immunohistochemistry and immunoelectron microscopy during the development of sieve element and tracheary element of stem in Cucurbita moschata Duch. Antibody with brown color （under light microscopy） and gold particles （under transmission electron microscopy） for detecting caspase 3-like protease was mainly displayed in inner phloem, external phloem and xylem in the region close to procambium. From the results it was considered that caspase 3-like protease did exist in vascular elements and played different roles during the development of sieve and tracheary elements, and different types of programmed cell death might be carried out. The caspase 3-like protease mainly participated in making cytoplasmic streaming cease and in degrading P-protein bodies; however, it rarely participated in the function for signal transferring in the developmental sieve element. However, it might induce calcium accumulation for rupturing the tonoplast in the signal of PCD in the developmental tracheary element.
