Functional annotation of a full-length mouse cDNA collection

The RIKEN Mouse Gene Encyclopaedia Project, a systematic approach to determining the full coding potential of the mouse genome, involves collection and sequencing of full-length complementary DNAs and physical mapping of the corresponding genes to the mouse genome. We organized an international functional annotation meeting (FANTOM) to annotate the first 21,076 cDNAs to be analysed in this project. Here we describe the first RIKEN clone collection, which is one of the largest described for any organism. Analysis of these cDNAs extends known gene families and identifies new ones.     

EL显示器的驱动电路设计

指出了传统EL显示器驱动电路存在的问题,用“平衡驱动”的概念,设计了矩阵式EL显示驱动电路系统。它包括高压驱动电路、逻辑控制电路、波形调制电路、电源电路和接口电路。该电路解决了非平衡驱动方式产生的“潜影”问题。     

X13—1菌体蛋白对小鼠免疫功能的影响

研究高蛋白含量的Fusarium菌株X13－1的最佳生长条件,并从菌丝体中获得了高达47％的菌体蛋白,再用热休克方法使其中RNA的含量降至2％以下,使之符合WHO标准,通过动物免疫实验证明,这种部分纯化的菌体蛋白可以增强小鼠的免疫功能。     

Nitric oxide mediates histamine induced down-regulation of H<Subscript>2</Subscript> receptor mRNA and internalization of the receptor protein (R1)

During agonist-dependent long-term stimulation of cells, histamine receptor subtypes are frequently down-regulated. However, the mechanisms underlying the modulation of receptor expression during long-term histamine stimulation have yet to be resolved. Based on our recently reported results showing an H₁-mediated down-regulation of histamine H₂ receptor mRNA in endothelial cells, our aim was to characterize the mechanism controlling rapid and long-term histamine-mediated modulation of H₂ receptor expression in more detail. We were able to show that the histamine-induced down-regulation of H₂ receptor mRNA and cell surface expression lasting for 24 h was accompanied by augmentation of the receptor protein level in the cytoplasmatic fraction of endothelial cells for this time period. Furthermore, changes in receptor protein levels in whole-cell lysate were negligible, indicating that the rapid and prolonged modulation of cell surface H₂ receptor levels by histamine was regulated solely via internalization. The role of nitric oxide (NO) as a key mediator in histamine-stimulated cell responses was underlined by subsequent studies showing the attenuation of histamine-induced H₂ receptor mRNA down-regulation and protein trafficking following NO synthase isozyme inhibition.Received 11 March 2003; received after revision 11 June 2003; accepted 17 June 2003     

Targeting of the Akt/PKB kinase to the actin skeleton

Serine/threonine kinase Akt/PKB intracellular distribution undergoes rapid changes in response to agonists such as Platelet-derived growth factor (PDGF) or Insulin-like growth factor (IGF). The concept has recently emerged that Akt subcellular movements are facilitated by interaction with nonsubstrate ligands. Here we show that Akt is bound to the actin skeleton in in situ cytoskeletal matrix preparations from PDGF-treated Saos2 cells, suggesting an interaction between the two proteins. Indeed, by immunoprecipitation and subcellular fractioning, we demonstrate that endogenous Akt and actin physically interact. Using recombinant proteins in in vitro binding and overlay assays, we further demonstrate that Akt interacts with actin directly. Expression of Akt mutants strongly indicates that the N-terminal PH domain of Akt mediates this interaction. More important, we show that the partition between actin bound and unbound Akt is not constant, but is modulated by growth factor stimulation. In fact, PDGF treatment of serum-starved cells triggers an increase in the amount of Akt associated with the actin skeleton, concomitant with an increase in Akt phosphorylation. Conversely, expression of an Akt mutant in which both Ser473 and Thr308 have been mutated to alanine completely abrogates PDGF-induced binding. The small GTPases Rac1 and Cdc42 seem to facilitate actin binding, possibly increasing Akt phosphorylation.Received 10 September 2003; accepted 25 September 2003     

A cryo-electron microscopic study of ribosome-bound termination factor RF2

Protein synthesis takes place on the ribosome, where genetic information carried by messenger RNA is translated into a sequence of amino acids. This process is terminated when a stop codon moves into the ribosomal decoding centre (DC) and is recognized by a class-1 release factor (RF). RFs have a conserved GGQ amino-acid motif, which is crucial for peptide release and is believed to interact directly with the peptidyl-transferase centre (PTC) of the 50S ribosomal subunit. Another conserved motif of RFs (SPF in RF2) has been proposed to interact directly with stop codons in the DC of the 30S subunit. The distance between the DC and PTC is approximately 73 A. However, in the X-ray structure of RF2, SPF and GGQ are only 23 A apart, indicating that they cannot be at DC and PTC simultaneously. Here we show that RF2 is in an open conformation when bound to the ribosome, allowing GGQ to reach the PTC while still allowing SPF-stop-codon interaction. The results indicate new interpretations of accuracy in termination, and have implications for how the presence of a stop codon in the DC is signalled to PTC.     

攀枝花方言词类考察

词类是词法的重要内容。本文在《攀枝花方言词形研究》的基础上,对攀枝花方言的词类作了全面考察。文中例举了各类词的土词词以及俗语的特殊说法和某些特殊用法。     

群体决策争议的支持模式研究

针对群体决策过程存在知识断层和决策争议的问题,讨论了对群体决策中的争议过程进行支持的Toulmin逻辑表达结构,并对将Toulmin逻辑结构应用于设计支持非结构群体过程的“公共大脑”的表达方式进行了探讨。