A small molecule Smac mimic potentiates TRAIL- and TNFalpha-mediated cell death     

Li L  Thomas RM  Suzuki H  De Brabander JK  Wang X  Harran PG 《Science (New York, N.Y.)》2004,305(5689):1471-1474

We describe the synthesis and properties of a small molecule mimic of Smac, a pro-apoptotic protein that functions by relieving inhibitor-of-apoptosis protein (IAP)-mediated suppression of caspase activity. The compound binds to X chromosome- encoded IAP (XIAP), cellular IAP 1 (cIAP-1), and cellular IAP 2 (cIAP-2) and synergizes with both tumor necrosis factor alpha (TNFalpha) and TNF-related apoptosis-inducing ligand (TRAIL) to potently induce caspase activation and apoptosis in human cancer cells. The molecule has allowed a temporal, unbiased evaluation of the roles that IAP proteins play during signaling from TRAIL and TNF receptors. The compound is also a lead structure for the development of IAP antagonists potentially useful as therapy for cancer and inflammatory diseases.  相似文献   

Orangutan cultures and the evolution of material culture     

van Schaik CP  Ancrenaz M  Borgen G  Galdikas B  Knott CD  Singleton I  Suzuki A  Utami SS  Merrill M 《Science (New York, N.Y.)》2003,299(5603):102-105

Geographic variation in some aspects of chimpanzee behavior has been interpreted as evidence for culture. Here we document similar geographic variation in orangutan behaviors. Moreover, as expected under a cultural interpretation, we find a correlation between geographic distance and cultural difference, a correlation between the abundance of opportunities for social learning and the size of the local cultural repertoire, and no effect of habitat on the content of culture. Hence, great-ape cultures exist, and may have done so for at least 14 million years.  相似文献   

Integrating what and when across the primate medial temporal lobe     

Naya Y  Suzuki WA 《Science (New York, N.Y.)》2011,333(6043):773-776

Episodic memory or memory for the detailed events in our lives is critically dependent on structures of the medial temporal lobe (MTL). A fundamental component of episodic memory is memory for the temporal order of items within an episode. To understand the contribution of individual MTL structures to temporal-order memory, we recorded single-unit activity and local field potential from three MTL areas (hippocampus and entorhinal and perirhinal cortex) and visual area TE as monkeys performed a temporal-order memory task. Hippocampus provided incremental timing signals from one item presentation to the next, whereas perirhinal cortex signaled the conjunction of items and their relative temporal order. Thus, perirhinal cortex appeared to integrate timing information from hippocampus with item information from visual sensory area TE.  相似文献   

A planar rhombic charge-separated tetrasilacyclobutadiene     

Suzuki K  Matsuo T  Hashizume D  Fueno H  Tanaka K  Tamao K 《Science (New York, N.Y.)》2011,331(6022):1306-1309

The cyclobutadiene (CBD) molecule C(4)H(4) deviates from a high-symmetry square geometry to compensate for its antiaromatic electronic structure. Here, we report a CBD silicon analog, Si(4)(EMind)(4) (1), stabilized by the bulky 1,1,7,7-tetraethyl-3,3,5,5-tetramethyl-s-hydrindacen-4-yl (EMind) groups, obtained as air- and moisture-sensitive orange crystals by the reduction of (EMind)SiBr(3) with three equivalents of lithium naphthalenide. X-ray crystallography reveals a planar and rhombic structure of the Si(4) four-membered ring, with alternating pyramidal and planar configurations at the silicon atoms. The large (29)Si chemical shift differences (Δδ > 350 parts per million) in the solid-state nuclear magnetic resonance spectra suggest a contribution of an alternately charge-separated structure. The rhombic-shaped charge-separated singlet state of compound 1 thus stabilizes its cyclic 4π-electron antiaromaticity in a manner that contrasts sharply with the bond-length alternation, characterizing the rectangular distortion of carbon-based CBD.  相似文献   

High-throughput mapping of a dynamic signaling network in mammalian cells     

Barrios-Rodiles M  Brown KR  Ozdamar B  Bose R  Liu Z  Donovan RS  Shinjo F  Liu Y  Dembowy J  Taylor IW  Luga V  Przulj N  Robinson M  Suzuki H  Hayashizaki Y  Jurisica I  Wrana JL 《Science (New York, N.Y.)》2005,307(5715):1621-1625

Signaling pathways transmit information through protein interaction networks that are dynamically regulated by complex extracellular cues. We developed LUMIER (for luminescence-based mammalian interactome mapping), an automated high-throughput technology, to map protein-protein interaction networks systematically in mammalian cells and applied it to the transforming growth factor-beta (TGFbeta) pathway. Analysis using self-organizing maps and k-means clustering identified links of the TGFbeta pathway to the p21-activated kinase (PAK) network, to the polarity complex, and to Occludin, a structural component of tight junctions. We show that Occludin regulates TGFbeta type I receptor localization for efficient TGFbeta-dependent dissolution of tight junctions during epithelial-to-mesenchymal transitions.  相似文献   

Bacterial rhodopsin: evidence for a new type of phototrophy in the sea     

Béjà O  Aravind L  Koonin EV  Suzuki MT  Hadd A  Nguyen LP  Jovanovich SB  Gates CM  Feldman RA  Spudich JL  Spudich EN  DeLong EF 《Science (New York, N.Y.)》2000,289(5486):1902-1906

Extremely halophilic archaea contain retinal-binding integral membrane proteins called bacteriorhodopsins that function as light-driven proton pumps. So far, bacteriorhodopsins capable of generating a chemiosmotic membrane potential in response to light have been demonstrated only in halophilic archaea. We describe here a type of rhodopsin derived from bacteria that was discovered through genomic analyses of naturally occuring marine bacterioplankton. The bacterial rhodopsin was encoded in the genome of an uncultivated gamma-proteobacterium and shared highest amino acid sequence similarity with archaeal rhodopsins. The protein was functionally expressed in Escherichia coli and bound retinal to form an active, light-driven proton pump. The new rhodopsin exhibited a photochemical reaction cycle with intermediates and kinetics characteristic of archaeal proton-pumping rhodopsins. Our results demonstrate that archaeal-like rhodopsins are broadly distributed among different taxa, including members of the domain Bacteria. Our data also indicate that a previously unsuspected mode of bacterially mediated light-driven energy generation may commonly occur in oceanic surface waters worldwide.  相似文献   

Phase-coherent amplification of matter waves     

Kozuma M  Suzuki Y  Torii Y  Sugiura T  Kuga T  Hagley EW  Deng L 《Science (New York, N.Y.)》1999,286(5448):2309-2312

Phase-coherent matter-wave amplification was demonstrated using Bose- Einstein-condensed rubidium-87 atoms. A small seed matter wave was created with coherent optical Bragg diffraction. Amplification of this seed matter wave was achieved by using the initial condensate as a gain medium through the superradiance effect. The coherence properties of the amplified matter wave, studied with a matter-wave interferometer, were shown to be locked to those of the initial seed wave. The active matter-wave device demonstrated here has great potential in the fields of atom optics, atom lithography, and precision measurements.  相似文献   

Cerebral GM1-gangliosidosis: chemical pathology of visceral organs   总被引：3，自引：0，他引：3  

K Suzuki 《Science (New York, N.Y.)》1968,159(3822):1471-1472

The livers and spleens from three patients with cerebral G(M1)-gangliosidosis contained greatly increased concentrations of a mucopolysaccharide tentatively identified as keratan sulfate. The concentration of a very soluble sialomucopolysaccharide was also increased. Concentrations of these compounds were not increased in the viscera of patients with Tay-Sachs disease (G(M2)-gangliosidosis). G(M1)-gangliosidosis appears to be a combined cerebral gangliosidosis and visceral mucopolysaccharidosis.  相似文献   

Atropinesterase and cocainesterase of rabbit serum: localization of the enzyme activity in isozymes   总被引：2，自引：0，他引：2  

C Stormont  Y Suzuki 《Science (New York, N.Y.)》1970,167(915):200-202

Zymograms reveal a multiplicity of esterase isozymes in rabbit serum. Most of the staining activity is concentrated in a region of the gels just anodal to the albumins where six phenotypes (A, AF, F, M, P, and S) are distinguished. The atropinesterase activity is associated with phenotypes A and AF and appears to be restricted to a single isozyme, zone A. Cocainesterase activity is limited to isozyme S, a zone common to all phenotypes except M.  相似文献   

Observation by light microscope of sugi (<Emphasis Type="Italic">Cryptomeria japonica</Emphasis>) treated with the ionic liquid 1-ethyl-3-methylimidazolium chloride     

Hisashi Miyafuji  Nobuyoshi Suzuki 《Journal of Wood Science》2011,57(5):459-461

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