检索结果-南通市图书馆

生物物理学报 2009年第S1期25卷 217-218页

作者： Shusen Liu state key {2. of {2. and membrane biotechnology, Instutute of zoology, Chinese Academy of Sciences, beijing, 100101, china

Although some fusogenic proteins have been established to tether two opposite outer or inner mitochondrial membranes into contact, a prerequisite for whole mitochondrial fusion events,

关键词： Mitochondrial membrane fusion Protein-tethering Lipid-bilayer-mixing and fusion Interfacial △pH of PMF.Inter-play between membrane fusion and ATP synthesis.

Dynamics of morphological changes for mitochondrial fission and fusion

在线全文

学校读者我要写书评

暂无评论

Science china(Physics,Mechanics & Astronomy) 2010年第4期53卷 680-689页

作者： WANG ShiQi 1,2.4 , FU ChangLiang 1,2., ZHANG Yan 1,2., CHEN Quan 3 & LONG Mian 1,2.1 key laboratory of Microgravity (National Microgravity laboratory), {2. 100190, china 2.Center for Biomechanics and Bioengineering, institute of Mechanics, Chinese Academy of Sciences, {2. 100190, china 3 state key laboratory of biomembrane and membrane biotechnology, institute of zoology, Chinese Academy of Sciences, beijing 100101, china 4 institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, {2. 100044, china 1. key laboratory of Microgravity (National Microgravity laboratory) Beijing 100190 China2. Center for Biomechanics and Bioengineering Institute of Mechanics Chinese Academy of Sciences Beijing 100190 China4. Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Beijing 100044 China3. State Key Laboratory of Biomembrane and Membrane Biotechnology Institute of Zoology Chinese Academy of Sciences Beijing 100101 China

Mitochondria experience continuous fusion and fission in a living cell, but their dynamics remains poorly quantified. Here a theoretical model was developed, upon a simplified population balance equation (PBE), to predict the morphological changes induced by mitochondrial fission and fusion. Assuming that both fission and fusion events are statistically independent, the survival probability of mitochondria staying in the fission or fusion state was formulated as an exponentially-decayed function with time, which depended on the time-dependent distribution of the mitochondrial volume and the fission and fusion rates. Parametric analysis was done for two typical volume distributions. One was Gamma distribution and the other was Gaussian distribution, derived from the measurements of volume distribution for individual mitochondria in a living cell and purified mitochondria in vitro. The predictions indicated that the survival probability strongly depended on morphological changes of individual mitochondria and was inversely correlated to the fission and fusion rates. This work provided a new insight into quantifying the mitochondrial dynamics via monitoring the evolution of the mitochondrial volume.

关键词： mitochondria morphology fission fusion dynamics modeling

Negative regulation of TGF-β signaling in development

在线全文

学校读者我要写书评

暂无评论

Cell Research 2004年第6期14卷 441-449页

作者： Ye Guang CHEN, An Ming MENG The state key {2. of {2. and membrane biotechnology, Department of Biological Sciences and biotechnology, Tsinghua University, beijing 100084, china Department of Biological Sciences and biotechnology The State Key Laboratory of Biomembrane and Membrane Biotechnology Tsinghua University Beijing 100084 China

The TGF-β superfamily members have important roles in controlling patterning and tissue formation in both invertebrates and vertebrates. Two types of signal transducers, receptors and Smads, mediate the signaling to regulate expression of their target genes. Despite of the relatively simple signal transduction pathway, many modulators have been found to contribute to a tight regulation of this pathway in a variety of mechanisms. This article reviews the negative regulation of TGF-β signaling with focus on its roles in vertebrate development.

关键词： TGF-β BMP Nodal Activin antagonist development negative regulation.

Electrophysiological research of synapse formation from beginning to maturity

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Chinese Science Bulletin 1998年第1期43卷 55-59页

作者： XIE Zuoping and ZHENG Yufang state key {2. of {2. and membrane Biotechnique Department of Biological Sciences and biotechnology, Tsinghua University, beijing 100084, china state key {2. of {2. and membrane Biotechnique Tsinghua University Beijing China Department of Biological Sciences and biotechnology Tsinghua University Beijing China

The development of synapses is an important question in neurobiology. We employ patchclamp technique to record MEPCs and EPCs of myoballs in Xenopus cell culture. The rate of EPC/MEPC is related with synapses maturation. Accordingly, we define the mature synapses as those whose rate of presynaptic membrane’s EPC to MEPC is more than 8. The process of maturation needs about 2.5 h after neurites contact with myoballs. We divide the development of synapses into three stages: young, developing and mature. The neurotransmitters stack gradually and increase by hundreds of times along with young synapses growing into maturity. So the process of synapses maturation should include presynaptic membrane specialization, postsynaptic membrane specialization and neurotransmitters stack.

关键词： definition of mature synapse α latrotoxin (α LTX) neurotransmitter stack.

Plant protein kinase genes induced by drought, high salt and cold stresses

在线全文

学校读者我要写书评

暂无评论

Chinese Science Bulletin 2000年第13期45卷 1153-1157页

作者： LIU Qiang , ZHANG Yong & Chen Shouyi1. Deparlmenl of Biological Science and biotechnology, Tsinghua University, beijing 100084,{2. 2. Department of Biological Science and biotechnology, Slate key laboratory of biomembrane and membrane biotechnology, Tsinghua University, beijing 100084,{2. 3. institute of Genetics, Chinese Academy of Sciences,{12.,{2. Department of Biological Science and biotechnology Tsinghua University Beijing China Department of Biological Science and biotechnology State Key Laboratory of Biomembrane and Membrane Biotechnology Tsinghua University Beijing China institute of Genetics Chinese Academy of Sciences Beijing China

Drought, high salt and cold are three different kinds of environment stresses that severely influence the growth, development and productivity of crops. They all decrease the water state of plant cells, and consequently result in the harm of plant from water deficit. Several genes encoding protein kinases and induced by drought, high salt and low temperature have been isolated from Arabidopsis. These protein kinases include receptor protein kinase (RPK), MAP kinases, ribosomal-protein kinases and transcription-regulation protein kinase. The expression features of these genes and the regulatory roles of these protein kinases in stress response and signal transduction are discussed.

关键词： protein kinase environment stress signal transduction gene expression.

Regulation of embryonic stem cell self-renewal and differentiation by TGF-β family signaling

在线全文

学校读者我要写书评

暂无评论

Science china(Life Sciences) 2010年第4期53卷 497-503页

作者： FEI Teng & CHEN Ye-Guang The state key {2. of {2. and membrane biotechnology, School of Life Sciences, Tsinghua University, beijing 100084, china 1. The state key {2. of {2. and membrane biotechnology School of Life Sciences Tsinghua University Beijing 100084 China

Embryonic stem (ES) cells are characterized by their ability to indefinitely self-renew and potential to differentiate into all the cell lineages of the body. ES cells are considered to have potential applications in regenerative medicine. In particular, the emergence of an ES cell analogue-induced pluripotent stem (iPS) cells via somatic cell reprogramming by co-expressing a limited number of critical stemness-related transcriptional factors has solved the problem of obtaining patient-specific pluripotent cells, encouraging researchers to develop more specific and functional cell lineages from ES or iPS cells for broad therapeutic applications. ES cell fate choice is delicately controlled by a core transcriptional network, epigenetic modification profiles and complex signaling cascades both intrinsically and extrinsically. Of these signals, transforming growth factor β (TGF-β) family members, including TGF-β, bone morphogenetic protein (BMP), Activin and Nodal, have been reported to influence cell self-renewal and a broad spectrum of lineage differentiation in ES cells, in accordance with the key roles of TGF-β family signaling in early embryo development. In this review, the roles of TGF-β family signals in coordinating ES cell fate determination are summarized.

关键词： embryonic stem cell TGF-β BMP Activin Nodal self-renewal differentiation

Structure and regulatory function of plant transcription factors

在线全文

学校读者我要写书评

暂无评论

Chinese Science Bulletin 2001年第4期46卷 271-278页

作者： LIU Qiang, ZHANG Guiyou & CHEN ShouyiDepartment of Biological Science and biotechnology, Tsinghua Univorsity, beijing 100084,{2. Department of Biological Science and biotechnology, state laboratory of biomembrane and membrane biotechnology, Tsinghua University, beijing 100084,{2. institute of Genetics, Chinese Academy of Sciences,{12.,{2. Department of Biological Science and biotechnology Tsinghua University Beijing China Department of Biological Science and biotechnology State Laboratory of Biomembrane and Membrane Biotechnology Tsinghua University Beijing China institute of Genetics Chinese Academy of Sciences Beijing China

The expression of inducible genes in plants is regulated by specific transcription factors at the transcrip-tional level. A typical transcription factor usually contains a DNA-binding domain, a transcription regulation domain, a dimerization site and a nuclear localization domain. These functional domains define the characteristic, localization and regulatory role of a transcription factor. Transcription factors recognize and bind to specific cis-acting elements or interact with other proteins, and then activate or repress the transcription of target genes by their functional domains. In recent years, elucidation on the structure and function of transcription factors has become an important subject in plant molecular biology.

关键词： transcription factor DNA-binding domain cis-acting element.

Molecular basis of cryptorchidism-induced infertility

在线全文

学校读者我要写书评

暂无评论

Science china(Life Sciences) 2010年第11期53卷 1274-1283页

作者： LIU YiXun & LI XiXia state key {2. of Reproductive Biology,{2., Chinese Academy of Sciences, beijing 100101, china 1. state key {2. of Reproductive Biology Institute of Zoology Chinese Academy of Sciences Beijing 100101 China

Artificial cryptorchidism or local testicular heat treatment can induce reversible oligospermia or azoospermia in monkeys and rats via germ cell apoptosis. Local warming of monkey testes in water at 43°C for 2.consecutive days (30 min per day) decreased the number of sperm in the semen by up to 80% on d 2., and the effect was completely reversed on d 144. Germ cells rely heavily on Sertoli cells for structural and nutritional support. Specialized junctions that play a pivotal role in spermatogenesis occur at sites of Sertoli-Sertoli and Sertoli-germ cell contact in the seminiferous epithelium. We demonstrated that expression of tight junction (TJ)-associated molecules, such as occludin and zonula occludens-1 (ZO-1), were greatly reduced 2.–48 h after heat treatment, while the permeability of the blood-testis barrier (BTB) was simultaneously increased, but recovered 10 d later. These results indicate a reversible disruption of the BTB associated with transient inductions of transforming growth factor (TGF) β2.and β3 expression, p38 mitogen-activated protein kinase and extracellular signal-regulated kinase activation, and concomitant loss of occludin and ZO-1. This suggests that expression of TJ-associated molecules and the BTB was reversibly perturbed by mild testicular hyperthermia, and that the heat-induced induction of TGF-β might be involved in downregulating TJ-associated proteins, leading to cell junction reduction. This review discusses the changes in total gene expression patterns after experimental cryptorchidism in adult mouse testes, and the cloning of several novel, physiologically significant spermatogenesis-specific genes.

关键词： cryptorchidism spermatogenesis apoptosis heat stress Sertoli cells blood-testis barrier tight junction

Role of ubiquitination in meiotic recombination repair

在线全文

学校读者我要写书评

暂无评论

Science china(Life Sciences) 2010年第4期53卷 447-454页

作者： CUI Li & LI Wei state key {2. of Reproductive Biology,{2., Chinese Academy of Sciences, beijing 100101, china 1. state key {2. of Reproductive Biology Institute of Zoology Chinese Academy of Sciences Beijing 100101 China

Programmed and unprogrammed double-strand breaks (DSBs) often arise from such physiological requirements as meiotic recombination, and exogenous insults, such as ionizing radiation (IR). Due to deleterious impacts on genome stability, DSBs must be appropriately processed and repaired in a regulatory manner. Recent investigations have indicated that ubiquitination is a critical factor in DNA damage response and meiotic recombination repair. This review summarizes the effects of proteins and complexes associated with ubiquitination with regard to homologous recombination (HR)-dependent DSB repair.

关键词： ubiquitin meiosis homologous recombination DNA double-strand breaks

A measurement error model for microarray data analysis

在线全文

学校读者我要写书评

暂无评论

Progress in Natural Science:Materials International 2005年第7期15卷 614-620页

作者： ZHOU Yiming and CHENG Jing ( Department of Biological Sciences and biotechnology, Tsinghua University, beijing 100084,{2. state key laboratory of biomembrane and membrane biotechnology, Tsinghua University, beijing 100084,{2. National Engineering Research Center for beijing Biochip Technology, 18 Life Science Parkway, beijing 102.06,{2.) Department of Biological Sciences and biotechnology Tsinghua University Beijing 100084 China. state key {2. of {2. and membrane biotechnology Tsinghua University Beijing 100084 China. National Engineering Research Center for beijing Biochip Technology 18 Life Science Parkway Beijing 102206 China

Microarray technology has been widely used to analyze the gene expression levels by detecting fluorescence intensity in a high throughput fashion. However, since the measurement error produced from various sources in microarray experiments is heterogeneous and too large to be ignored, we propose here a measurement error model for microarray data processing, by which the standard deviation of the measurement error is demonstrated to be linearly increased with fluorescence intensity. A robust algorithm, which estimates the parameters of the measurement error model from a single microarray without replicated spots, is provided. The model and algorithm for estimating of the parameters from a given data set are tested on both the real data set and the simulated data set, and the result has been proven satisfactory. And, combining the measurement error model with traditional Z-test method, a full statistical model has been developed It can significantly improve the statistical inference for identifying differentially expressed genes.

关键词： microarray measurement error model parameter estimation differentially expressed genes.