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The Rice RMR1 Associates with a Distinct Prevacuolar Compartment for the Protein Storage Vacuole Pathway

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Molecular Plant 2011年第5期4卷 854-868页

作者： Yun Shen Junqi Wang Yu Ding Sze Wan Lo Guillaume Gouzerh Jean-Marc Neuhau Liwen Jiang School of Life Sciences Centre for Cell and Developmental Biology The Chinese University of Hong Kong Shatin New Territories Hong Kong China Laboratory of Cell and Molecular Biology University of Neuchatel CH-2000 Neuchatel Switzerland

Transport of vacuolar proteins from Golgi apparatus or trans-Golgi network （TGN） to vacuoles is a receptor-mediated process via an intermediate membrane-bound prevacuolar compartment （PVC） in plant cells. Both vacuolar sorting receptor （VSR） and receptor homology region-transmembrane domain-RING-H2 （RMR） proteins have been shown to function in transporting storage proteins to protein storage vacuole （PSV）, but little is known about the nature of the PVC for the PSV pathway. Here, we use the rice RMR1 （OsRMR1） as a probe to study the PSV pathway in plants. Immunogold electron microscopy （EM） with specific OsRMR1 antibodies showed that OsRMR1 proteins were found in the Golgi apparatus, TGN, and a distinct organelle with characteristics of PVC in both rice culture cells and developing rice seeds, as well as the protein body type II （PBII） or PSV in developing rice seeds. This organelle, also found in both tobacco BY-2 and Arabidopsis suspension cultured cells, is morphologically distinct from the VSR-positive multivesicular lytic PVC or multivesicular body （MVB） and thus represent a PVC for the PSV pathway that we name storage PVC （sPVC）. Further in vivo and in vitro interaction studies using truncated OsRMR1 proteins secreted into the culture media of transgenic BY-2 suspension cells demonstrated that OsRMR1 functions as a sorting receptor in transporting vicilin-like storage proteins.

关键词： PSV RMR storage PVC sorting receptor transport pathway.

Vacuolar Sorting Receptor （VSR） Proteins Reach the Plasma Membrane in Germinating Pollen Tubes

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Molecular Plant 2011年第5期4卷 845-853页

作者： Hao Wang Xiao-Hong Zhuang Stefan Hillmer David G. Robinson Li-Wen Jiang School of Life Sciences Centre for Cell and Developmental Biology The Chinese University of Hong Kong Shatin New Territories Hong Kong China State Key Laboratory of Agrobiotechnology The Chinese University of Hong Kong Shatin New Territories Hong Kong China Department of Cell Biology Heidelberg Institute for Plant Science University of Heidelberg Germany

Vacuolar sorting receptors （VSRs） are type I integral membrane proteins that mediate the vacuolar transport of soluble cargo proteins via prevacuolar compartments （PVCs） in plants. Confocal immunofluorescent and immunogold Electron Microscope （EM） studies have localized VSRs to PVCs or multivesicular bodies （MVBs） and trans-Golgi network （TGN） in various plant cell types, including suspension culture cells, root cells, developing and germinating seeds. Here, we provide evidence that VSRs reach plasma membrane （PM） in growing pollen tubes. Both immunofluorescent and immunogold EM studies with specific VSR antibodies show that, in addition to the previously demonstrated PVC/MVB localization, VSRs also localize to PM in lily and tobacco pollen tubes prepared from chemical fixation or high-pressure freezing/frozen substitution. Such a PM localization suggests an additional role of VSR proteins in mediating protein transport to PM and endocytosis in growing pollen tubes. Using a high-speed Spinning Disc Confocal Microscope, the possible fusion between VSR-positive PVC organelles and the PM was also observed in living tobacco pollen tubes transiently expressing the PVC reporter GFP-VSR. In contrast, the lack of a prominent PM localization of GFP-VSR in living pollen tubes may be due to the highly dynamic situation of vesicular transport in this fast-growing cell type.

关键词： Plasma membrane pollen tube vacuolar sorting receptor.

Density-Functional Fidelity Approach to Quantum Phase Transitions

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Chinese Physics Letters 2009年第2期26卷 208-211页

作者：顾世建 Department of Physics and ITP The Chinese University of Hong Kong Hong Kong

We propose a new approach to quantum phase transitions in terms of the density-functional fidelity, which measures the similarity between density distributions of two ground states in parameter space. The key feature of the approach is such that the density-functional fidelity can be measured easily in experiments. Both the validity and versatility of the approach are checked by the Lipkin-Meshkov-Glick model and the one-dimensional Hubbard model.

关键词： field emission molybdenum dioxide enhancement factor

Responses of terrestrial bryophytes to simulated climate change in a secondary evergreen broad-leaved forest in southern China

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Journal of Forestry Research 2022年第5期33卷 1481-1492页

作者： Jiewei Hao L.M.Chu School of Life Sciences The Chinese University of Hong KongHong Kong SARChina 2 College of Ecology and Environment Hainan University58 Renmin RoadHaikou 570228China

Tropical regions are biodiversity hotspots and are well-suited to explore the potential influence of global climate change on forest ecosystems. Bryophytes have essential ecological functions in tropical forest ecosystems, but knowledge of the potential impact of global warming and possible changes in water availability patterns on terrestrial bryophytes is limited. We transplanted eight terres- trial moss species from two elevations (900 and 500 m) to warmer and drier elevations (500 and 100 m) during a halfyear observation period on Tai Mo Shan, southern China. The simulated climate change resulted in severely declined health status and marked decrease in growth of the trans- planted species when compared with their performance at the original elevations. Five of the eight selected species survived for six months after being transplanted to the warmer and drier lowlands, though their health status deteriorated severely. Sematophyllum subhumile , Pseudotaxiphyllum pohliaecarpum and Brachythecium buchananii were highly susceptible to changes in temperature and rainfall patterns and might be used as suitable bioindicators. As the tropics are expected to become hotter and drier, terrestrial mosses might be negatively affected or even be at risk of extinction. Bryophytes in the tropics could represent one of the best biological communities to reflect the direct adverse impact of climate change and provide early warning of the biological outcomes induced by ongoing climate crisis.

关键词： Bioindicator Bryophytes Climate change Secondary forest Terrestrial mosses

Maximizing Thermal Entanglement of XY Model Using Site-Dependent Magnetic Fields in Specific Directions

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Chinese Physics Letters 2008年第3期25卷 832-835页

作者：陈文岭杨东顾世建 Department of Physics and ITP The Chinese University of Hong Kong Hong Kong Laboratory for Quantum Information and Department of Physics China Jiliang University Hangzhou 310018

We study the thermal entanglement by means of concurrence in a two-qubit isotropic XY model in the presence of site-dependent external magnetic fields in arbitrary directions. We find that at a given temperature and magnetic field strength, the mirror symmetry of the two fields about the x-y plane is a necessary condition for maximum entanglement. However, if there is no constraint on the field strengths, then the necessary condition for maximum entanglement reduces to the configuration that the two fields are vertical, anti-parallel and with the same strength. We also investigate the anisotropic XY model and find that the above conclusion more or less holds.

关键词： supernova explosion proto-neutron star shock wave

Copper catalyzed/mediated direct B–H alkenylation/alkynylation in carboranes

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Science China Chemistry 2019年第1期62卷 74-79页

作者： Yu Chen Yik Ki Au Yangjian Quan Zuowei Xie Department of Chemistry and State Key Laboratory of Synthetic Chemistry The Chinese University of Hong Kong

Base metal catalyzed regioselective cage B–H functionalization has been achieved. Under the assistance of a bidentate directing group, Cu-catalyzed [4+2] annulation of carboranyl amides with internal alkynes affords unprecedented C,B-substituted carborane-fused-pyridone derivatives, whereas the use of terminal alkynes leads to B–H/C(sp)–H dehydrocoupling products. The isolation and structural identification of a notably stable Cu(Ⅰ) intermediate shed light on the reaction mechanism, which is proposed to involve a Cu(Ⅲ) intermediate.

关键词： [4+2] annulation alkynylation B-H activation base metal catalysis carborane

DIRECT MEASUREMENT OF WEAK DEPLETION FORCE BETWEEN TWO SURFACES

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Chinese Journal of Polymer Science 2011年第1期29卷 1-11页

作者： Xiang-jun Gong Xiao-chen Xing Xiao-ling Wei To Ngai Department of Chemistry the Chinese University ofHong Kong Shatin N.T. Hong Kong China Department of Physics the Chinese University ofHong Kong Shatin N.T. Hong Kong China

In a mixture of colloidal particles and polymer molecules, the particles may experience an attractive ＂depletion force＂ if the size of the polymer molecule is larger than the interparticle separation. This is because individual polymer molecules experience less conformational entropy if they stay between the particles than they escape the inter-particle space, which results in an osmotic pressure imbalance inside and outside the gap and leads to interparticle attraction. This depletion force has been the subject of several studies since the 1980s, but the direct measurement of this force is still experimentally challenging as it requires the detection of energy variations of the order of kBT and beyond. We present here our results for applying total internal reflection microscopy （TIRM） to directly measure the interaction between a free-moving particle and a flat surface in solutions consisting of small water-soluble organic molecules or polymeric surfactants. Our results indicate that stable nanobubbles （ca. 150 nm） exist free in the above aqueous solutions. More importantly, the existence of such nanobubbles induces an attraction between the spherical particle and flat surface. Using TIRM, we are able to directly measure such weak interaction with a range up to 100 nm. Furthermore, we demonstrate that by employing thermo^sensitive microgel particles as a depleting agent, we are able to quantitatively measure and reversibly control kBT-scale depletion attraction as function of solution pH.

关键词： Depletion interaction Total internal reflection microscopy (TIRM) Nanobubbles Microgel particles

Supplementary Material: Stepping Stone Mechanism: Carrier-Free Long-Range Magnetism Mediated by Magnetized Cation States in Quintuple Layer

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Chinese Physics Letters 2018年第1期35卷 99-103页

作者： Chunkai Chan Xiaodong Zhang Yiou Zhang Kinfai Tse Bei Deng Jingzhao Zhang Junyi Zhu Department of Physics Chinese University of Hong Kong

The long-range magnetism observed in group-V tellurides quintuple layers is the only working example of carrierfree dilute magnetic semiconductors(DMS),whereas the physical mechanism is unclear,except the speculation on the band topology enhanced van Vleck *** on DFT calculations,we find a stable longrange ferromagnetic order in a single quintuple layer of Cr-doped Bi_(2)Te_(3) or Sb_(2)Te_(3),with the dopant separation more than 9?.This configuration is the global energy minimum among all *** from the conventional super exchange theory,the magnetism is facilitated by the lone pair derived anti-bonding states near the *** anti-bonding states work as stepping stones merged in the electron sea and conduct ***,spin orbit coupling induced band inversion is found to be insignificant in the ***,our findings directly dismiss the common misbelief that band topology is the only factor that enhances the *** further demonstrate that removal of the lone pair derived states destroys the long-range *** novel mechanism sheds light on the fundamental understanding of long-range magnetism and may lead to discoveries of new classes of DMS.

关键词： Topology

RELATION BETWEEN COHERENT STRUCTURE AND SCALING LAW IN RAYLEIGH-BENARD CONVECTION BASED ON WAVELET TRANSFORMATION

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Journal of Hydrodynamics 2004年第4期16卷 436-441页

作者： FUQiang JIANGMin XIAKe-qing SchoolofScience P.L.A.UniversityofScienceandTechnologyNanjing211101China Departmentofphysics TheChineseUniversityofHongKongHongKongChina SchoolofScience P.L.A.UniversityofScienceandTechnologyNanjing211101China Departmentofphysics TheChineseUniversityofHongKongHongKongChina

In this paper, the Extended Self Similarity (ESS) was used to study thescaling exponent ξ(q) of temperature data in the Reyleigh-Benard convection and its variation withexperimental measuring locations. The results show that ξ(q) varies with locations and agrees wellwith experimental data. And then the wavelet transformation is used to extract the coherentstructure, by means of the definition of a called non-coherent signal. we can understand theinfluence of coherent structure on ξ(q) and the relations between large scale vortex motions andsmall ones.

关键词： scaling law coherent structure wavelet transformation rayleigh-benardconvection