Negative regulation of Wingless signaling by D-axin, a Drosophila homolog of axin     

Hamada F  Tomoyasu Y  Takatsu Y  Nakamura M  Nagai S  Suzuki A  Fujita F  Shibuya H  Toyoshima K  Ueno N  Akiyama T 《Science (New York, N.Y.)》1999,283(5408):1739-1742

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Diurnal changes in the partial pressure of carbon dioxide in coral reef water     

Kayanne H  Suzuki A  Saito H 《Science (New York, N.Y.)》1995,269(5221):214-216

Coral reefs are considered to be a source of atmospheric carbon dioxide because of their high calcium carbonate production and low net primary production. This was tested by direct measurement of diurnal changes in the partial pressure of carbon dioxide (Pco(co2)) in reef waters during two 3-day periods, one in March 1993 and one in March 1994, on Shiraho reef of the Ryukyu Islands, Japan. Although the Pco(co2) values in reef waters exhibited large diurnal changes ranging from 160 to 520 microatmospheres, they indicate that the reef flat area is a net sink for atmospheric carbon dioxide. This suggests that the net organic production rate of the reef community exceeded its calcium carbonate production rate during the observation periods.  相似文献   

Interferon-gamma: the major mediator of resistance against Toxoplasma gondii   总被引：55，自引：0，他引：55  

Y Suzuki  M A Orellana  R D Schreiber  J S Remington 《Science (New York, N.Y.)》1988,240(4851):516-518

Mice were injected with a monoclonal antibody to interferon-gamma to examine the importance of endogenous production of this lymphokine in resistance against infection with the sporozoan parasite Toxoplasma gondii. Mice with intraperitoneal infections of T. gondii that received no antibody survived and developed chronic T. gondii infection, whereas the infected mice that received the monoclonal antibody died of toxoplasmosis. The activation of macrophages, which kill T. gondii in vivo, was inhibited by administration of the monoclonal antibody, but the production of antibodies to T. gondii was not suppressed. The fact that an antibody to interferon-gamma can eliminate resistance to acute Toxoplasma infection in mice suggests that this lymphokine is an important mediator of host resistance to this parasite.  相似文献   

Giant hepatic mitochondria: production in mice fed with cuprizone   总被引：2，自引：0，他引：2  

K Suzuki 《Science (New York, N.Y.)》1969,163(862):81-82

Giant mitochondria in hepatocytes that have the average size of nuclei can be consistently produced in the liver of weanling mice by feeding them cuprizone (bis-cyclohexanone oxaldihydrazone). The simplicity of the procedure and the consistency of the results make the feeding of cuprizone a new and useful experimental tool for the study of mitochondrial metabolism.  相似文献   

Axle-less F1-ATPase rotates in the correct direction     

Furuike S  Hossain MD  Maki Y  Adachi K  Suzuki T  Kohori A  Itoh H  Yoshida M  Kinosita K 《Science (New York, N.Y.)》2008,319(5865):955-958

F1-adenosine triphosphatase (ATPase) is an ATP-driven rotary molecular motor in which the central gamma subunit rotates inside a cylinder made of three alpha and three beta subunits alternately arranged. The rotor shaft, an antiparallel alpha-helical coiled coil of the amino and carboxyl termini of the gamma subunit, deeply penetrates the central cavity of the stator cylinder. We truncated the shaft step by step until the remaining rotor head would be outside the cavity and simply sat on the concave entrance of the stator orifice. All truncation mutants rotated in the correct direction, implying torque generation, although the average rotary speeds were low and short mutants exhibited moments of irregular motion. Neither a fixed pivot nor a rigid axle was needed for rotation of F1-ATPase.  相似文献   

Molecular cloning of the Bombyx mori prothoracicotropic hormone   总被引：17，自引：0，他引：17  

A Kawakami  H Kataoka  T Oka  A Mizoguchi  M Kimura-Kawakami  T Adachi  M Iwami  H Nagasawa  A Suzuki  H Ishizaki 《Science (New York, N.Y.)》1990,247(4948):1333-1335

Prothoracicotropic hormone (PTTH), a brain secretory polypeptide of insects, stimulates the prothoracic glands to produce and release ecdysone, the steroid essential to insect development. The complementary DNAs encoding PTTH of the silkmoth Bombyx mori were cloned and characterized, and the complete amino acid sequence was deduced. The data indicated that PTTH is first synthesized as a 224-amino acid polypeptide precursor containing three proteolytic cleavage signals. The carboxyl-terminal component (109 amino acids) that follows the last cleavage signal represents one PTTH subunit. Two PTTH subunits are linked together by disulfide bonds, before or after cleavage from prepro-PTTH, to form a homodimeric PTTH. When introduced into Escherichia coli cells, the complementary DNA directed the expression of an active substance that was functionally indistinguishable from natural PTTH. In situ hybridization showed the localization of the prepro-PTTH mRNA to two dorsolateral neurosecretory cells of the Bombyx brain.  相似文献   

Differentiation of immature mucous cells into parietal, argyrophil, and chief cells in stomach grafts   总被引：2，自引：0，他引：2  

M Matsuyama  H Suzuki 《Science (New York, N.Y.)》1970,169(943):385-387

Microscopic and submicroscopic studies on regenerating gastric mucosa neonatally grafted in the subcutaneous tissue of littermate mice have revealed that immature mucous cells are totipotent; ultimately they transform into mature mucous, parietal, argyrophil, and chief cells in the gastric glands.  相似文献   

Collection,mapping, and annotation of over 28,000 cDNA clones from japonica rice   总被引：2，自引：0，他引：2  

Rice Full-Length cDNA Consortium;National Institute of Agrobiological Sciences Rice Full-Length cDNA Project Team  Kikuchi S  Satoh K  Nagata T  Kawagashira N  Doi K  Kishimoto N  Yazaki J  Ishikawa M  Yamada H  Ooka H  Hotta I  Kojima K  Namiki T  Ohneda E  Yahagi W  Suzuki K  Li CJ  Ohtsuki K  Shishiki T;Foundation of Advancement of International Science Genome Sequencing & Analysis Group  Otomo Y  Murakami K  Iida Y  Sugano S  Fujimura T  Suzuki Y  Tsunoda Y  Kurosaki T  Kodama T  Masuda H  Kobayashi M  Xie Q  Lu M 《Science (New York, N.Y.)》2003,301(5631):376-379

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Success and virulence in Toxoplasma as the result of sexual recombination between two distinct ancestries     

Grigg ME  Bonnefoy S  Hehl AB  Suzuki Y  Boothroyd JC 《Science (New York, N.Y.)》2001,294(5540):161-165

Toxoplasma gondii is a common human pathogen causing serious, even fatal, disease in the developing fetus and in immunocompromised patients. Despite its ability to reproduce sexually and its broad geographic and host range, Toxoplasma has a clonal population structure comprised principally of three lines. We have analyzed 15 polymorphic loci in the archetypal type I, II, and III strains and found that polymorphism was limited to, at most, two rather than three allelic classes and no polymorphism was detected between alleles in strains of a given type. Multilocus analysis of 10 nonarchetypal isolates likewise clustered the vast majority of alleles into the same two distinct ancestries. These data strongly suggest that the currently predominant genotypes exist as a pandemic outbreak from a genetic mixing of two discrete ancestral lines. To determine if such mixing could lead to the extreme virulence observed for some strains, we examined the F(1) progeny of a cross between a type II and III strain, both of which are relatively avirulent in mice. Among the progeny were recombinants that were at least 3 logs more virulent than either parent. Thus, sexual recombination, by combining polymorphisms in two distinct and competing clonal lines, can be a powerful force driving the natural evolution of virulence in this highly successful pathogen.  相似文献   

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