Daisuke Maruyama

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The atomic force microscope (AFM) is a powerful tool for imaging individual biological molecules attached to a substrate and placed in aqueous solution. At present, however, it is limited by the speed at which it can successively record highly resolved images. We sought to increase markedly the scan speed of the AFM, so that in the future it can be used to(More)
Callose (β-1,3 glucan) separates developing pollen grains, preventing their underlying walls (exine) from fusing. The pollen tubes that transport sperm to female gametes also contain callose, both in their walls as well as in the plugs that segment growing tubes. Mutations in CalS5, one of several Arabidopsis β-1,3 glucan synthases, were previously shown to(More)
J domain-containing proteins (J proteins) are functional partners for heat shock protein 70 (Hsp70) molecular chaperones and mediate various cellular processes by regulating activities of Hsp70. Budding yeast has three J proteins in the endoplasmic reticulum (ER): Scj1p and Jem1p functioning in protein folding and quality control in the ER, and Sec63p(More)
In animal fertilization, multiple sperms typically arrive at an egg cell to "win the race" for fertilization. However, in flowering plants, only one of many pollen tubes, conveying plant sperm cells, usually arrives at each ovule that harbors an egg cell. Plant fertilization has thus been thought to depend on the fertility of a single pollen tube. Here we(More)
Nuclear fusion is an essential process in the sexual reproduction of animals and plants. In flowering plants, nuclear fusion occurs three times: once during female gametogenesis, when the two polar nuclei fuse to produce the diploid central cell nucleus, and twice during double fertilization. The yeast Ig binding protein (BiP) is a molecular chaperone Hsp70(More)
In flowering plants, double fertilization is normally accomplished by the first pollen tube, with the fertilized ovule subsequently inhibiting the attraction of a second pollen tube. However, the mechanism of second-pollen-tube avoidance remains unknown. We discovered that failure to fertilize either the egg cell or the central cell compromised(More)
Semantic Web services and their composition portend a future where the Web can behave more intelligently for solving general real-life problems. To solve such real-life problems requires a set of appropriate services to be composed via planning, scheduled, and then executed: those are logical services composition, physical composition, and execution. Web(More)
Solving general real-life problems requires a set of appropriate services to be composed via planning, scheduled, and then executed. Web service composition is the most difficult aspect and is our focus. In this paper, we describe a new framework for intelligent semantic Web services that supports the planning and scheduling aspects by a combined HTN(More)
In animals, microtubules and centrosomes direct the migration of gamete pronuclei for fertilization. By contrast, flowering plants have lost essential components of the centrosome, raising the question of how flowering plants control gamete nuclei migration during fertilization. Here, we use Arabidopsis thaliana to document a novel mechanism that regulates(More)
In flowering plants, fertilization-dependent degeneration of the persistent synergid cell ensures one-on-one pairings of male and female gametes. Here, we report that the fusion of the persistent synergid cell and the endosperm selectively inactivates the persistent synergid cell in Arabidopsis thaliana. The synergid-endosperm fusion causes rapid dilution(More)