Isolation and expression studies of the ERD15 gene involved in drought-stressed responses.

The early response to the dehydration 15 (ERD15) gene is widely involved in the processes of signal transduction, programmed cell death, gene transcription, and stress tolerance in plants. In a previous study, the ERD15 gene was shown to be an important regulator of the abscisic acid response and salicylic acid-dependent defense pathway, acting as an important negative regulator of abscisic acid. The complete IbERD15 gene (accession No. KF723428) was isolated by reverse transcription-polymerase chain reaction. The IbERD15 gene contains an open reading frame of 504 bp, encodes a peptide of 167 amino acids, and has a molecular mass of 18.725 kDa. The transcript levels of the IbERD15 gene in a variety of tissues were examined by digital gene expression profiling. The roots of the sweet potato were treated by 3 degrees of polyethylene glycol, and the results indicate that the IbERD15 gene might play an important role in the defense response to drought stress. Moreover, the IbERD15 gene was successfully transformed into yeast cells for analysis of drought tolerance in transgenic yeast.

DNA hypomethylation is crucial for apoptotic DNA to induce systemic lupus erythematosus-like autoimmune disease in SLE-non-susceptible mice.

OBJECTIVES: Systemic lupus erythematosus (SLE) is characterized by serological presence of anti-double-stranded DNA (dsDNA) antibodies and its pathogenesis remains unclarified. Our previous work found that syngeneic activated lymphocyte-derived DNA (ALD-DNA) induced SLE-like autoimmune disease in the SLE-non-prone BALB/c mice. Here, the biological and chemical characteristics of the somatic DNA were focused upon to investigate their contribution to the autoimmunity induction to provide clues for the understanding of the pathogenesis of SLE in non-susceptible strains. METHODS: Induction of anti-dsDNA antibodies, glomerulonephritis and proteinuria was evaluated in BALB/c mice after subcutaneous immunization with apoptotic DNA (annexin-V+) extracted from concanavalin A or UV-treated apoptotic splenocytes or necrotic DNA from necrotic splenocytes. The hypomethylated apoptotic DNA and the normal DNA were then methylated and demethylated, respectively, by CpG methylase or 5-azacytidine treatment to re-evaluate their immunogenicity in BALB/c mice. RESULTS: It was apoptotic but not necrotic DNA that induced SLE-like autoimmune disease and the level of apoptotic DNA was associated with the level of anti-dsDNA antibodies. The apoptotic DNA exhibited significantly lower methylation levels than the normal DNA. Methylation of the hypomethylated apoptotic DNA significantly impaired its ability to induce anti-dsDNA antibodies and proteinuria, while demethylation of the normal or necrotic DNA endowed them with the immunogenicity to induce the SLE-like syndrome. CONCLUSIONS: Our study provides direct evidence showing that DNA hypomethylation is essential for apoptotic DNA to induce SLE-like autoimmune disease in non-susceptible mice, which may help in elucidating the pathogenesis of SLE.

Development of multi-channel Doppler spectroscopic measurement system using 8 × 8 multianode photomultiplier tube assembly.

Using an 8 × 8 channel photomultiplier tube assembly and a single Czerny-Turner monochromator, we have developed a novel Doppler spectroscopic system which can measure the time evolutions of spectral distribution of plasma emission from eight different lines of sight simultaneously. An optical lens system is employed to couple the output of the monochromator with the detector assembly, resulting in small cross-talks less than 5% in spatial distribution together with large magnification of up to 50 in wavelength direction. The suggested system yields cost-effective polychromatic measurements of eight spatial channels with uniform optical and electrical characteristics.

Development of effective power supply using electric double layer capacitor for static magnetic field coils in fusion plasma experiments.

A cost-effective power supply for static magnetic field coils used in fusion plasma experiments has been developed by application of an electric double layer capacitor (EDLC). A prototype EDLC power supply system was constructed in the form of a series LCR circuit. Coil current of 100 A with flat-top longer than 1 s was successfully supplied to an equilibrium field coil of a fusion plasma experimental apparatus by a single EDLC module with capacitance of 30 F. The present EDLC power supply has revealed sufficient performance for plasma confinement experiments whose discharge duration times are an order of several seconds.