• Molecules and Cells
• /
• v.25 no.4
• /
• pp.559-565
• /
• 2008

Members of the TGA family of basic domain/leucine zipper transcription factors regulate defense genes through physical interaction with NON-EXPRESSOR OF PR1 (NPR1). Of the seven TGA family members, TGA4/octopine synthase (ocs)-element-binding factor 4 (OBF4) is the least understood. Here we present evidence for a novel function of OBF4 as a regulator of flowering. We identified CONSTANS (CO), a positive regulator of floral induction, as an OBF4-interacting protein, in a yeast two-hybrid library screen. OBF4 interacts with the B-box region of CO. The abundance of OBF4 mRNA cycles with a 24 h rhythm under both long-day (LD) and short-day (SD) conditions, with significantly higher levels during the night than during the day. Electrophoretic mobility shift assays revealed that OBF4 binds to the promoter of the FLOWERING LOCUS T (FT) gene, a direct target of CO. We also found that, like CO and FT, an OBF4:GUS construct was prominently expressed in the vascular tissues of leaf, indicating that OBF4 can regulate FT expression through the formation of a protein complex with CO. Taken together, our results suggest that OBF4 may act as a link between defense responses and flowering.

• Journal of the Optical Society of Korea
• /
• v.19 no.3
• /
• pp.255-259
• /
• 2015

We have proposed and experimentally verified a pulse-width modulation (PWM) generator which directly generated a PWM signal in the optical domain. Output waveforms were clear at the repetition rate of 16 MHz; the duty cycle (DC) was from 14.7% to 72.1%; and the DC-control resolution was about 4.399%/dB. The PWM generator' operation principle is based on the injection-locking property of a single-mode Fabry-$P{\acute{e}}rot$ laser diode (SMFP-LD). The SMFP-LD, which has a self-locked mode wavelength at ${\lambda}_{PWM}$, was used to detect the power of the injection-locking signal (optical analog input). If the analog input power is high, the SMFP-LD is locked to the wavelength of the input signal ${\lambda}_a$ and there is no output after an optical bandpass filter (OBF). If the analog input power is low, the SMFP-LD is unlocked and there is output signal at ${\lambda}_{PWM}$ after the OBF. Thus, the SMFP-LD plus the OBF provide digital output for an analog input. The DC of the output PWM signal can be controlled by tuning the power of the analog input.

• YAKHAK HOEJI
• /
• v.41 no.2
• /
• pp.181-186
• /
• 1997

A series of 7-deazahypoxanthine and 7-deazaadenine derivatives[6,7.8.9.10,13] as purine antagonists was prepared. The pyrrolidine-5-one derivatives[4,11] were treated vith $(C_2H_5)_3OBF_4$ to give 3- aryl-5-ethoxy-2H-3,4-dihydropyrrole[5,12], which were converted to 7-aryl-7,8-dihydro-7(9H)-deazahy-poxanthine[6,7,8,9,10] and 7-phenyl-2-methyl-7,8- dihydro-7(9H)-deazaadenine[13].

• YAKHAK HOEJI
• /
• v.37 no.3
• /
• pp.228-234
• /
• 1993

A new series of 7-deazapurine derivatives[7,8] as purine antagonists was prepared. Diethyl 4-cyano-N-(diphenyimethylene)-3-arylglutamate[3] were synthesized by LDA-catalyzed Michael addition of N-(diphenylrnethylene)glycine ethyl ester with (E)-2-cyano-3-arylacrylate. Deprotection yields diethyl 4-cyano-3-arylglutamate, which were easily cyclized to 4-cyano-2-ethoxycarbonyl-5-oxo-3-arylpyrrolidine[4]. The compounds[4] were treated with NaBH$_{4}$ and then with (C$_{2}$H$_{5}$)$_{3}$OBF$_{4}$ to give 4-cyano-5-ethoxy-2H-2-ethoxymethyl-3-aryl-3,4-dihydropyrrole[6], which were converted to 7-aryl-6-amino-8-ethoxymethyl-7,8-dihydro-7(3H, 9H)-deazapurine-2-thione[7] and 7-aryl-2,6-diamino-8-ethoxymethyl-7,8-dihydro-7(9H)-deazapurine[8] with possible activity against neoplastic disease.

• Journal of Applied Biological Chemistry
• /
• v.53 no.4
• /
• pp.212-218
• /
• 2010

This study was aimed to investigate the contents of chemical components and the biological activity of fermented Omija (Schizandra chinensis Baillon.) beverage (FOB), which have not been well known up to now. General compositions and the contents of mineral and vitamin of FOB were lower than Omija before fermentation (OBF). In addition, most sucrose was digested into glucose and fructose in FOB. This suggests that the beneficial contents may be made from general compositions by fermentation, though more evidences are needed. Antioxidant activity of FOB was measured by using 2,2-diphenyl-l-picryl-hydrazyl (DPPH) free radical scavenging activity and superoxide dismutase-like activity (SODA). DPPH radical scavenging activity and SODA were increased in a dose-dependent manner, and were about 79.7% and 60.8% at four times diluted FOB (25% of FOB), respectively. The FOB also showed strong antibacterial activity on Escherichia coli. Beauty effect of FOB was demonstrated by the analysis of tyrosinase and elastase inhibitory activities, and they were remarkably increased in a dose-dependent manner. Tyrosinase inhibitory activity was about 82% at two times diluted FOB (50% of FOB) and elastase inhibitory activity was 78.2% at five times diluted FOB (20% of FOB). These results suggest that FOB has a strong antioxidant activity, and tyrosinase and elastase inhibitory effects.