This paper proved that octodecyl propylenediamine could form vesicles in pure water and aqueous solution of CuCl2 or Cu(NO3)2. The structure and morphology of vesicles were different when the copper (Ⅱ) salt was ...This paper proved that octodecyl propylenediamine could form vesicles in pure water and aqueous solution of CuCl2 or Cu(NO3)2. The structure and morphology of vesicles were different when the copper (Ⅱ) salt was added to the solution. The results showed that both the counterions and the ligands had strong influence on the configuration of coordinated structures and packing model in bilayer membrane of vesicles.展开更多
Polarized tip growth is a fundamental cellular process in many eukaryotes. In this study, we examined the dynamic restructuring of the actin cytoskeleton and its relationship to vesicle transport during pollen tip gro...Polarized tip growth is a fundamental cellular process in many eukaryotes. In this study, we examined the dynamic restructuring of the actin cytoskeleton and its relationship to vesicle transport during pollen tip growth in Arabidopsis. We found that actin filaments originating from the apical membrane form a specialized structure consisting of longitudinally aligned actin bundles at the cortex and inner cytoplasmic fila- ments with a distinct distribution. Using actin-based pharmacological treatments and genetic mutants in combination with FRAP (fluorescence recovery after photobleaching) technology to visualize the transport of vesicles within the growth domain of pollen tubes, we demonstrated that cortical actin filaments facilitate tip-ward vesicle transport. We also discovered that the inner apical actin filaments prevent backward movement of vesicles, thus ensuring that sufficient vesicles accumulate at the pollen tube tip to support the rapid growth of the pollen tube. The combinatorial effect of cortical and internal apical actin filaments perfectly explains the generation of the inverted "V" cone-shaped vesicle distribution pattern at the pollen tube tip. When pollen tubes turn, apical actin filaments at the facing side undergo depolymerization and repolymerization to reorient the apical actin structure toward the new growth direction. This actin restructuring precedes vesicle accumulation and changes in tube morphology. Thus, our study provides new insights into the functional relationship between actin dynamics and vesicle transport during rapid and directional pollen tube growth.展开更多
We report in this study the identification of a natural product-like antagonist(1a) of Vps34 as a potent autophagy modulator via structure-based virtual screening. Aurone derivative 1a strongly inhibited Vps34 activit...We report in this study the identification of a natural product-like antagonist(1a) of Vps34 as a potent autophagy modulator via structure-based virtual screening. Aurone derivative 1a strongly inhibited Vps34 activity in cell-free and cell-based assays. Significantly, 1a prevents autophagy in human cells induced either by starvation or by an mT OR inhibitor. In silico modeling and kinetic data revealed that 1a could function as an ATP-competitive inhibitor of Vps34. Moreover, it suppressed autophagy in vivo and without inducing heart or liver damage in mice. 1a could be utilized as a new motif for more selective and efficacious antagonists of Vps34 for the potential treatment of autophagy-related human diseases.展开更多
Silica hollow spheres(SHSs) have attracted great attention because of their low toxicity, low density, large surface area, high chemical and thermal stability, and surface permeability. They can be widely applied in...Silica hollow spheres(SHSs) have attracted great attention because of their low toxicity, low density, large surface area, high chemical and thermal stability, and surface permeability. They can be widely applied in storage^[l], catalysis^[2], drug deli- very^[3,4], low-dielectric-constant materials^[5], low-refractive materials^[6-8], and so on. Up to now, there have been various methods to produce SHSs. Inorganic^[9] or organic particles^[10], such as polystyrene or calcium carbonate, were used as hard templates to create hollow cavities, However, the multistep synthetic process and the lack of structural robustness of the shells upon template removal process weaken their applica- tion. Soft templates, including oil-in-water emulsions^[11,12], vesicles^[13], micelle^[14,15] and gas bubbles^[16], are applied widely.展开更多
文摘This paper proved that octodecyl propylenediamine could form vesicles in pure water and aqueous solution of CuCl2 or Cu(NO3)2. The structure and morphology of vesicles were different when the copper (Ⅱ) salt was added to the solution. The results showed that both the counterions and the ligands had strong influence on the configuration of coordinated structures and packing model in bilayer membrane of vesicles.
基金This work was supported by grants from the Ministry of Science and Technology of China (2013CB945100) and the National Natural Science Foundation of China (31671390 and 31471266). X.Q. was supported by post-doctoral fellowships from Tsinghua-Peking Joint Center for Life Sciences and the China Postdoctoral Science Foundation (grant no. 2015M571028).
文摘Polarized tip growth is a fundamental cellular process in many eukaryotes. In this study, we examined the dynamic restructuring of the actin cytoskeleton and its relationship to vesicle transport during pollen tip growth in Arabidopsis. We found that actin filaments originating from the apical membrane form a specialized structure consisting of longitudinally aligned actin bundles at the cortex and inner cytoplasmic fila- ments with a distinct distribution. Using actin-based pharmacological treatments and genetic mutants in combination with FRAP (fluorescence recovery after photobleaching) technology to visualize the transport of vesicles within the growth domain of pollen tubes, we demonstrated that cortical actin filaments facilitate tip-ward vesicle transport. We also discovered that the inner apical actin filaments prevent backward movement of vesicles, thus ensuring that sufficient vesicles accumulate at the pollen tube tip to support the rapid growth of the pollen tube. The combinatorial effect of cortical and internal apical actin filaments perfectly explains the generation of the inverted "V" cone-shaped vesicle distribution pattern at the pollen tube tip. When pollen tubes turn, apical actin filaments at the facing side undergo depolymerization and repolymerization to reorient the apical actin structure toward the new growth direction. This actin restructuring precedes vesicle accumulation and changes in tube morphology. Thus, our study provides new insights into the functional relationship between actin dynamics and vesicle transport during rapid and directional pollen tube growth.
基金supported by Hong Kong Baptist University (FRG2/ 16–17/007, FRG2/17–18/003, China)the Health and Medical Research Fund (HMRF/14150561, China)+9 种基金the Research Grants Council (HKBU/12301115, China)the National Natural Science Foundation of China (21575121 and 21775131, China)the Hong Kong Baptist University Century Club Sponsorship Scheme 2018 (China)the Interdisciplinary Research Matching Scheme (RC-IRMS/16–17/03, China)Interdisciplinary Research Clusters Matching Scheme (RC-IRCs/17–18/03, China)Innovation and Technology Fund (ITS/260/16FX, China), Matching Proof of Concept Fund (MPCF-001–2017/18, China)Collaborative Research Fund (C5026-16G, China), SKLEBA and HKBU Strategic Development Fund (SKLP_1718_P04, China)the Science and Technology Development Fund, Macao SAR (0072/ 2018/A2, China)the University of Macao (MYRG2016-00151ICMS-QRCM and MYRG2018-00187-ICMS, China)a Discovery Project Grant (DP160101682, Australia) from the Australian Research Council
文摘We report in this study the identification of a natural product-like antagonist(1a) of Vps34 as a potent autophagy modulator via structure-based virtual screening. Aurone derivative 1a strongly inhibited Vps34 activity in cell-free and cell-based assays. Significantly, 1a prevents autophagy in human cells induced either by starvation or by an mT OR inhibitor. In silico modeling and kinetic data revealed that 1a could function as an ATP-competitive inhibitor of Vps34. Moreover, it suppressed autophagy in vivo and without inducing heart or liver damage in mice. 1a could be utilized as a new motif for more selective and efficacious antagonists of Vps34 for the potential treatment of autophagy-related human diseases.
基金Supported by the National Natural Science Foundation of China(No.20890121)the National Basic Research Program of China(No.2009CB930403)
文摘Silica hollow spheres(SHSs) have attracted great attention because of their low toxicity, low density, large surface area, high chemical and thermal stability, and surface permeability. They can be widely applied in storage^[l], catalysis^[2], drug deli- very^[3,4], low-dielectric-constant materials^[5], low-refractive materials^[6-8], and so on. Up to now, there have been various methods to produce SHSs. Inorganic^[9] or organic particles^[10], such as polystyrene or calcium carbonate, were used as hard templates to create hollow cavities, However, the multistep synthetic process and the lack of structural robustness of the shells upon template removal process weaken their applica- tion. Soft templates, including oil-in-water emulsions^[11,12], vesicles^[13], micelle^[14,15] and gas bubbles^[16], are applied widely.