We measured strand breaks of pBR322 plasmid DNA irradiated with ultrasoft X-rays using monochromatic synchrotron radiation as a light source. Three photon energies, 388, 435 and 573 eV, a value below and above the nitrogen K-edge and above the oxygen K-edge, respectively, were chosen for the irradiation experiments as they have an equivalent photon transmittance of the sample. Irradiated DNA was analyzed by agarose gel electrophoresis and the numbers of single- and double-strand breaks (ssb and dsb) were determined by measuring the band intensity on the gel after ethidium bromide staining. The action cross-sections for the ssb and dsb slightly increased with the photon energy. The ratio between 388 and 573 eV was about 1.5 for both forms of strand breaks. The absorbed energy required for a strand break was about 60 eV for ssb and 1 keV for dsb, less than one fifth of the values obtained previously in the 2 keV region. On the other hand, the absorbed energies per strand break, as well as the ratio of the action cross-section for the ssb to that for the dsb, were constant regardless of the photon energy used. The K-shell photoabsorption on carbon, nitrogen and oxygen atoms in the DNA molecule, followed by an Auger cascade, induced DNA strand breaks with a constant efficiency in terms of the absorbed energy. These results indicate that the strand breaks of the DNA molecule in the solid state are mainly caused by the photo- and Auger-electrons and the efficiency of the strand breaks little depends on the atoms ejecting these secondary electrons.

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The Svp26 protein of S. cerevisiae is an ER- and Golgi-localized integral membrane protein with 4 potential membrane-spanning domains. It functions as an adaptor protein that facilitates the ER exit of Ktr3, a mannosyltransferase required for biosynthesis of O-linked oligosaccharides, and the ER exit of Mnn2 and Mnn5, mannosyltransferases, which participate in the biosynthesis of N-linked oligosaccharides. Ktr3 belongs to the Kre2 family, which consists of 9 members of type-II membrane proteins sharing sequence similarities. In this report, we examined all Kre2 family members and found that the Golgi localizations of two others, Kre2 and Ktr1, were dependent on Svp26 by immunofluorescence microscopy and cell fractionations in sucrose density gradients. We show that Svp26 functions in facilitating the ER exit of Kre2 and Ktr1 by an in vitro COPII budding assay. Golgi localization of Ktr4 was not dependent on Svp26. Screening null mutants of the genes encoding abundant COPII membrane proteins for those showing mislocalization of Ktr4 in the ER revealed that Erv41 and Erv46 are required for the correct Golgi localization of Ktr4. We provide biochemical evidence that the Erv41-Erv46 complex functions as an adaptor protein for ER exit of Ktr4. This is the first demonstration of the molecular function of this evolutionally conserved protein complex. The domain switching experiments show that the lumenal domain of Ktr4 is responsible for recognition by the Erv41-Erv46 complex. Thus, ER exit of Kre2-family proteins is dependent on distinct adaptor proteins and our results provide new insights into the traffic of Kre2-family mannosyltransferases.

-The Electric Vehicle (EV) is clean and environmental friendly vehicle. However, its power source, electricity still contains fossils. To reduce the fossil utilization, the authors established the Renewable Energy for Electric Vehicle (RE-EV) project. In this paper, two research topics are studied. One is a study of actual operation data to obtain the potential of the EV with PV electricity. An EV (i-MiEV) manufactured by Mitsubishi Motors Corporation was operated for 1 year. In this project, a charging station consisting of a 2.6 kW Photovoltaic power generation (PV) system with a 9 kWh battery system and measuring equipment was installed in Ookayama campus in Tokyo Institute of Technology. This system maximizes the PV electricity and minimizes grid electricity while charging the EV. Second is a statistical study to estimate CO 2 emissions for various kinds of driving patterns. In this paper, 6 driving patterns from statistical data and 1 actual data were studied by Life-Cycle Assessment (LCA) approach to estimate CO 2 emissions. As a result, 80% of charging electricity is from PV from actual operation data.Regarding the LCA, CO 2 emissions of EV with PV electricity are same with utility electricity at short distance driving pattern and much better at long distance driving patterns, even when the system uses lead acid battery. And CO 2 emissions of all EV driving patterns are smaller than those of a gasoline vehicle.