We demonstrate an easy and scalable low-temperature process to convert porous ternary complex metal oxide nanoparticles from solution-synthesized core^shell metal oxide nanopartides by thermal annealing. The final pro...We demonstrate an easy and scalable low-temperature process to convert porous ternary complex metal oxide nanoparticles from solution-synthesized core^shell metal oxide nanopartides by thermal annealing. The final products demonstrate superior electrochemical properties with a large capacity and high stability during fast charging/discharging cycles for potential applications as advanced lithium-ion battery （LIB） electrode materials. In addition, a new breakdown mechanism was observed on these novel electrode materials.展开更多
Rho family small GTPases are universal signaling switches in the control of cell polarity in eukaryotic cells. Their polar distribution to the cell cortex is critical for the execution of their functions, yet the mech...Rho family small GTPases are universal signaling switches in the control of cell polarity in eukaryotic cells. Their polar distribution to the cell cortex is critical for the execution of their functions, yet the mechanism for this distribution is poorly understood. Using a yeast two-hybrid method, we identified RIP1 （ROP interactive partner 1）, which belongs to a family of five members of novel proteins that share a C-terminal region that interacts with ROP. When expressed in Arabidopsis pollen, green fluorescence protein GFP-tagged RIP1 was localized to the nucleus of mature pollen. When pollen grains were hydrated in germination medium, GFP-RIP1 switched from the nucleus to the cell cortex at the future pollen germination site and was maintained in the apical cortex of germinating pollen and growing pollen tubes. RIP1 was found to interact with ROP1 in pollen tubes, and the cortical RIP1 localization was influenced by the activity of ROP1. Overexpression of RIP1 induced growth depolarization in pollen tubes, a phenotype similar to that induced by ROP1 overexpression. Interestingly, RIP1 overexpression enhanced GFP-ROP1 recruitment to the plasma membrane （PM） of pollen tubes. Based on these observations, we hypothesize that RIP1 is involved in the positive feedback regulation of ROP1 localization to the PM, leading to the establishment of a polar site for pollen germination and pollen tube growth.展开更多
基金The authors acknowledge the support from the National Science Foundation Electronic and Photonic Materials （No. 1206425） and the startup fund from Iowa State University. Y. W. also thanks the support from the Eastern Scholar Program.
文摘We demonstrate an easy and scalable low-temperature process to convert porous ternary complex metal oxide nanoparticles from solution-synthesized core^shell metal oxide nanopartides by thermal annealing. The final products demonstrate superior electrochemical properties with a large capacity and high stability during fast charging/discharging cycles for potential applications as advanced lithium-ion battery （LIB） electrode materials. In addition, a new breakdown mechanism was observed on these novel electrode materials.
基金This work is supported by grants from Department of Energy （DEFG02-04ER15555） and National Science Foundation （MCB0111082） to Z.Y.We thank members of the Yang lab and Lord lab for their stimulating discussion. No conflict of interest declared.
文摘Rho family small GTPases are universal signaling switches in the control of cell polarity in eukaryotic cells. Their polar distribution to the cell cortex is critical for the execution of their functions, yet the mechanism for this distribution is poorly understood. Using a yeast two-hybrid method, we identified RIP1 （ROP interactive partner 1）, which belongs to a family of five members of novel proteins that share a C-terminal region that interacts with ROP. When expressed in Arabidopsis pollen, green fluorescence protein GFP-tagged RIP1 was localized to the nucleus of mature pollen. When pollen grains were hydrated in germination medium, GFP-RIP1 switched from the nucleus to the cell cortex at the future pollen germination site and was maintained in the apical cortex of germinating pollen and growing pollen tubes. RIP1 was found to interact with ROP1 in pollen tubes, and the cortical RIP1 localization was influenced by the activity of ROP1. Overexpression of RIP1 induced growth depolarization in pollen tubes, a phenotype similar to that induced by ROP1 overexpression. Interestingly, RIP1 overexpression enhanced GFP-ROP1 recruitment to the plasma membrane （PM） of pollen tubes. Based on these observations, we hypothesize that RIP1 is involved in the positive feedback regulation of ROP1 localization to the PM, leading to the establishment of a polar site for pollen germination and pollen tube growth.
