篮球队队员之间协作的博弈分析

用博弈的斗鸡、鹰鸽、囚徒困境的理论对篮球队队员之间冲突和矛盾发生的各种现象及原因进行探讨,从而提高篮球队在训练和比赛中队员间的协作效率.     

多功能开放型企业供需网成员企业合作关系的经济模型

多功能开放型企业供需网(SDN)合作伙伴关系的稳定性,将直接决定SDN创新管理理念的生命力和未来发展前景,传统企业间的一次性静态博弈和供应链(SC)盟员间的有限次重复博弈,都是低效的合作关系,因而其稳定性较差,无限次重复博弈以及由此而引发的触发策略,能够实现帕累托最优的纳什均衡,是SDN合作伙伴关系稳定发展的深层经济学原因,通过建立SDN成员企业合作关系的经济模型,论证了SDN的稳定性。     

2'-O methylation of the viral mRNA cap evades host restriction by IFIT family members

Cellular messenger RNA (mRNA) of higher eukaryotes and many viral RNAs are methylated at the N-7 and 2'-O positions of the 5' guanosine cap by specific nuclear and cytoplasmic methyltransferases (MTases), respectively. Whereas N-7 methylation is essential for RNA translation and stability, the function of 2'-O methylation has remained uncertain since its discovery 35 years ago. Here we show that a West Nile virus (WNV) mutant (E218A) that lacks 2'-O MTase activity was attenuated in wild-type primary cells and mice but was pathogenic in the absence of type I interferon (IFN) signalling. 2'-O methylation of viral RNA did not affect IFN induction in WNV-infected fibroblasts but instead modulated the antiviral effects of IFN-induced proteins with tetratricopeptide repeats (IFIT), which are interferon-stimulated genes (ISGs) implicated in regulation of protein translation. Poxvirus and coronavirus mutants that lacked 2'-O MTase activity similarly showed enhanced sensitivity to the antiviral actions of IFN and, specifically, IFIT proteins. Our results demonstrate that the 2'-O methylation of the 5' cap of viral RNA functions to subvert innate host antiviral responses through escape of IFIT-mediated suppression, and suggest an evolutionary explanation for 2'-O methylation of cellular mRNA: to distinguish self from non-self RNA. Differential methylation of cytoplasmic RNA probably serves as an example for pattern recognition and restriction of propagation of foreign viral RNA in host cells.     

Inhibitory effect of the adenovirus type 5 E1A protein expressed in the yeast system

The human adenovirus type 5 E1A, a tumor- suppressor gene[1], codes for two major related proteins of 243 amino acids (12S) and 289 amino acids (13S) by al-ternative splicing in two exons[2]. Studies have been shown that E1A can regulate expression of many genes and cell cycle[3]. Both in vitro and in vivo experiments indicated that E1A could induce tumor cells differentia-tion, convert tumor cells into an epithelial phenotype, in-hibit tumor cell growth and metastasis and strongly en-ha…     

FZD蛋白家族的起源与演化分析

FZD(Frizzled)蛋白家族是Wnt信号通路的跨膜受体,在动物发育过程中起着非常关键的作用.通过对不同物种(从单细胞动物到哺乳动物)基因组中FZD家族基因的检索,发现FZD蛋白家族起源于早期的、与海绵动物具有共同祖先的后生动物.进化分析结果表明,FZD蛋白家族分为4个亚家族:FZD1/2/3/4/6/7亚家族、FZD5/8亚家族、FZD4亚家族和FZD9/10亚家族;不同亚家族之间的motif组成不同,但在C端都含有一个保守的KTXXXW motif.进化速率分析结果表明,尽管FZD蛋白家族成员在演化过程中受到较强的纯化选择,但是在其基因发生复制或motif组成变化的分支上仍有正选择的作用.该结果可为进一步理解FZD蛋白家族的起源与演化动态提供一定的参考.     

An immunologically active chimaeric protein containing herpes simplex virus type 1 glycoprotein D

Herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2) cause both persistent and latent infections, including recurrent cutaneous disease, lethal neonatal disease, central nervous system disease and other clinical syndromes. Modified live vaccines or conventionally prepared subunit vaccines have generally been unsuccessful in the treatment of HSV-1 and HSV-2 infections from the standpoints of safety and efficacy. It has been established that HSV-1 and HSV-2 infectivity may be neutralized in vitro with antisera directed specifically against each of the four major glycoproteins of the virus (gA/gB, gC, gD and gE) and antisera against glycoprotein gD, of either HSV-1 or HSV-2, are capable of neutralizing both HSV-1 and HSV-2 infectivity in vitro and in vivo. We have previously reported on the identification, DNA sequence and expression at low level in Escherichia coli of the gD gene of HSV-1 strain Patton. Here we describe construction of a hybrid gene encoding a chimaeric protein containing HSV-1 gD, bacteriophage lambda Cro and E. coli beta-galactosidase (gD-beta-gal) protein, which is expressed at high level in E. coli. Moreover, the chimaeric protein elicits antibodies in rabbits that not only immunoprecipitate gD from cells infected with HSV-1 and HSV-2 but also neutralize HSV-1 and HSV-2 infectivity in vitro.     

The type IV mucolipidosis-associated protein TRPML1 is an endolysosomal iron release channel

TRPML1 (mucolipin 1, also known as MCOLN1) is predicted to be an intracellular late endosomal and lysosomal ion channel protein that belongs to the mucolipin subfamily of transient receptor potential (TRP) proteins. Mutations in the human TRPML1 gene cause mucolipidosis type IV disease (ML4). ML4 patients have motor impairment, mental retardation, retinal degeneration and iron-deficiency anaemia. Because aberrant iron metabolism may cause neural and retinal degeneration, it may be a primary cause of ML4 phenotypes. In most mammalian cells, release of iron from endosomes and lysosomes after iron uptake by endocytosis of Fe(3+)-bound transferrin receptors, or after lysosomal degradation of ferritin-iron complexes and autophagic ingestion of iron-containing macromolecules, is the chief source of cellular iron. The divalent metal transporter protein DMT1 (also known as SLC11A2) is the only endosomal Fe(2+) transporter known at present and it is highly expressed in erythroid precursors. Genetic studies, however, suggest the existence of a DMT1-independent endosomal and lysosomal Fe(2+) transport protein. By measuring radiolabelled iron uptake, by monitoring the levels of cytosolic and intralysosomal iron and by directly patch-clamping the late endosomal and lysosomal membrane, here we show that TRPML1 functions as a Fe(2+) permeable channel in late endosomes and lysosomes. ML4 mutations are shown to impair the ability of TRPML1 to permeate Fe(2+) at varying degrees, which correlate well with the disease severity. A comparison of TRPML1(-/- )ML4 and control human skin fibroblasts showed a reduction in cytosolic Fe(2+) levels, an increase in intralysosomal Fe(2+) levels and an accumulation of lipofuscin-like molecules in TRPML1(-/-) cells. We propose that TRPML1 mediates a mechanism by which Fe(2+) is released from late endosomes and lysosomes. Our results indicate that impaired iron transport may contribute to both haematological and degenerative symptoms of ML4 patients.     

Structure of the fibronectin type 1 module

The rapid accumulation of sequence data has provided insight into the evolution of proteins and led to the identification of 'mosaic proteins'. These proteins have evolved by duplication, insertion and deletion of a common pool of structural units or modules, yet their biological functions are diverse. They are involved in cell adhesion and migration, embryogenesis and the pathways of blood clotting, fibrinolysis and complement. The modular units are defined by 'consensus sequences' which often include conserved disulphide bonds. Despite the available sequence information, little is known of the tertiary structure of mosaic proteins. If, however, the 'consensus structure' of the modules were known, valuable structural information could be inferred about a wide variety of proteins and biological systems. An important mosaic protein is fibronectin, an extracellular matrix protein that consists of three types of module (see refs 3, 7 for reviews). Here we describe the structure of the fibronectin type 1 module which appears twelve times in fibronectin and is also found in factor XII and tissue plasminogen activator. The module was produced using a yeast expression system and the structure was determined in solution using 1H NMR. This methodology promises to be extremely powerful in the investigation of modules from a wide range of mosaic proteins.     

A novel protein family mediates Casparian strip formation in the endodermis

Polarized epithelia are fundamental to multicellular life. In animal epithelia, conserved junctional complexes establish membrane diffusion barriers, cellular adherence and sealing of the extracellular space. Plant cellular barriers are of independent evolutionary origin. The root endodermis strongly resembles a polarized epithelium and functions in nutrient uptake and stress resistance. Its defining features are the Casparian strips, belts of specialized cell wall material that generate an extracellular diffusion barrier. The mechanisms localizing Casparian strips are unknown. Here we identify and characterize a family of transmembrane proteins of previously unknown function. These 'CASPs' (Casparian strip membrane domain proteins) specifically mark a membrane domain that predicts the formation of Casparian strips. CASP1 displays numerous features required for a constituent of a plant junctional complex: it forms complexes with other CASPs; it becomes immobile upon localization; and it sediments like a large polymer. CASP double mutants display disorganized Casparian strips, demonstrating a role for CASPs in structuring and localizing this cell wall modification. To our knowledge, CASPs are the first molecular factors that are shown to establish a plasma membrane and extracellular diffusion barrier in plants, and represent a novel way of epithelial barrier formation in eukaryotes.     

关于型为1nu1的Frame MOLS的谱

由 Ｉ Ｓ Ｏ Ｌ Ｓ的存在性可知除去 Ｆ Ｍ Ｏ Ｌ Ｓ（１６）不存在和另外 １５ 个可能的例外的情况： （ｎ，ｕ）＝ （２ｕ ＋ ２，ｕ），ｕ ∈｛２，４，６，８，１０，１４，１６，１８，２０，２２，２６，２８，３２，３４，４６｝ 外，当ｎ ≥２ｕ ＋ １ 时 Ｆ Ｍ Ｏ Ｌ Ｓ（１ｎｕ１） 存在。本文对以上所有可能的例外，证明 Ｆ Ｍ Ｏ Ｌ Ｓ（１ｎｕ１） 的存在性。     

总蛋白含量不同的水稻品种谷蛋白含量分析及Gt1启动子序列比较

选取3种总蛋白含量差异较大的水稻为材料,在分析其谷蛋白含量的基础上,克隆它们的Gt1启动子,并采用vector NTI软件对这3个Gt1启动子序列进行比较．结果显示,在不同总蛋白和谷蛋白含量的水稻品种中,Gt1谷蛋白基因启动子是有差异的．     

Inhibitory effect of the adenovirus type 5 E1A protein expressed in the yeast system on the human tumor cell growth

Adenovirus 5 type E1A as a tumor suppressor gene can inhibit tumor growth and enhance the sensitivity of chemotherapy and radiotherapy. E1A have the ability to integrate into the host genome, resulting in long-time expression that induces Rb gene inactivation and animal cells immortalization. This prompted us to select the E1A protein for treatment of cancer in order to overcome the limitations of E1A gene therapy. Thus, we firstly constructed E1A eucaryotic expression vector (pPIC9/E1A), transformated the pichia pastoris yeast cells (GS115) and screened the high-expressing recombinant strains. The positive yeast strains were cultured in the shake flask, and induced for 3 d. The crude E1A protein was purified using two steps of column chromatography on HiTrap Q and HiTrap SP. The purified E1A protein was identified by SDS-PAGE and Western blot. E1A protein was mostly located at cellular nuclear when Chariot delivered E1A protein into cells. The analysis in vitro indicated that the E1A protein arrested LN686 cell cycle at G2/M phase, and significantly inhibited the growth of LN686 tumor cells. The current studies firstly provided an experimental basis to further develop E1A protein for tumor treatment.     

Inhibitory effect of the adenovirus type 5 E1A protein expressed in the yeast system of the human tumor cell growth

Adenovirus 5 type E1A as a tumor suppressor gene can inhibit tumor growth and enhance the censitivity of chemotherapy and radiotherapy.E1A have the ability to integrate into the host genome,resulting in long-time expres-sion that induces Rb gene inactivation and animal cells im-mortalization.This prompted us to select the E1A protein for treatment of cancer in order to overcome the limitations of E1A gene therapy.Thus,we firstly comstructed E1A eu-caryotic expression vector (pPIC9/E1A),transformated the pichia pastoris yeast cells(GS115) and screened the high-expressing recombinant strains.The positive yeast strains were cultured in the shake flask,and induced for 3d.The crude E1A protein was purified using two steps of col-umu chromatography on HiTrap Q and HiTrap SP.The pu-rified E1A protein was identified by SDS-PAGE and Western blot.E1A protein was mostly located at cellular unclear when Cheriot delivered E1A protein into cells.The analysis in vitro indicated that the E1A protein arrested LN686 cell cycle at G2/M phase,and significantly inhibited the growth of LN686 tumor cells.The current studies firstly provided an experimental basis to further develop E1A protein for tumor treatment.     

Ligand-receptor binding revealed by the TNF family member TALL-1

The tumour necrosis factor (TNF) ligand TALL-1 and its cognate receptors, BCMA, TACI and BAFF-R, were recently identified as members of the TNF superfamily, which are essential factors contributing to B-cell maturation. The functional, soluble fragment of TALL-1 (sTALL-1) forms a virus-like assembly for its proper function. Here we determine the crystal structures of sTALL-1 complexed with the extracellular domains of BCMA and BAFF-R at 2.6 and 2.5 A, respectively. The single cysteine-rich domain of BCMA and BAFF-R both have saddle-like architectures, which sit on the horseback-like surface formed by four coil regions on each individual sTALL-1 monomer. Three novel structural modules, D2, X2 and N, were revealed from the current structures. Sequence alignments, structural modelling and mutagenesis revealed that one disulphide bridge in BAFF-R is critical for determining the binding specificity of the extracellular domain eBAFF-R to TALL-1 instead of APRIL, a closely related ligand of TALL-1, which was confirmed by binding experiments in vitro.     

南亚实蝇气味结合蛋白家族基因的筛选及克隆验证

为初步了解南亚实蝇对引诱剂的感受机制,笔者基于南亚实蝇转录组数据进行了气味结合蛋白(odorant-binding protein,简称OBP)家族基因的筛选和克隆验证.共筛选出OBPs基因32条,成功克隆出26条,对其编码蛋白的结构分析表明,典型OBPs 21条,DimerOBPs 1条,Minus-OBPs、Plus-COBPs各2条.碱基序列分析和蛋白进化分析表明,这26条基因与瓜实蝇OBPs高度相似,其编码的蛋白质与瓜实蝇亲缘关系最近,有16条与瓜实蝇聚类数值达90以上.这为下一步南亚实蝇OBPs高级结构和功能的研究提供了基础数据,也为实蝇引诱机制的探讨提供了理论依据.     

菠菜SoSWEET蛋白家族基因鉴定与表达分析

以现有菠菜基因组信息为基础,通过生物信息学方法筛选鉴定16个菠菜SoSWEET蛋白家族成员,命名为SoSWEET1~SoSWEET16.氨基酸残基数量在648~1 140之间,分子质量在54 070.32~95 868.64 u之间,理论等电点（pI）在5.06~5.19之间.亚细胞定位预测有6个SoSWEET蛋白定位于细胞膜,5个SoSWEET蛋白定位于内质网,5个SoSWEET蛋白定位于细胞膜、内质网.系统进化分析将菠菜SoSWEET蛋白家族分成4个亚族,在此基础上对基因结构、保守基序、顺式作用调控元件等进行分析.共鉴定了10个高度保守基序,其中所有菠菜SoSWEET蛋白都包含基序1,2和4,是构成菠菜SoSWEET蛋白中最高度保守的部分.所有菠菜SoSWEET蛋白家族成员都含MtN3_slv和PQ-loop superfamily结构域.大多数SoSWEET蛋白家族的基因含有5个内含子.顺式作用元件预测结果表明,菠菜SoSWEET基因启动子上包含光响应、生长发育、植物激素响应和逆境胁迫响应等顺式作用元件.组织表达分析表明,所有SoSWEET基因在根、茎、叶和叶柄中都有表达,霜霉病胁迫处理后16个基因表现出不同响应变化.本研究为后续深入研究菠菜SoSWEET蛋白家族成员的功能提供了重要参考.