Effects of Ethylsalicylic Acid on Growth and Rubisco/Rubisco Activase in Tobacco Plant Cultured under Cadmium Treatment in vitro

Growth induced by cadmium (Cd) and ethylsalicylic acid (ESA) and the effect of ESA on rubisco/rubisco activase were studied in tobacco. The effect of denaturants on rubisco/rubisco activase was also investigated. In order to determine optimal concentration of ESA for growth of tobacco, tobacco was treated with $10^{-6}$-10 mM. It was found that its growth was the highest at $10^{-4}$ mM ESA. In the experiment using control, Cd treated group, ESA treated group, and Cd and ESA mixture group, ESA alone showed the highest growth and Cd showed the lowest growth. Cd treated group was the lowest in both rubisco/rubisco activase content and activity. ESA reduced the rubisco/rubisco activase content, but increased their activity. The activity of rubisco was inhibited by treating L-cysteine, urea, thiourea, ${\beta}$-mercaptoethanol, and EDTA other than guanidine-HCl in control group. L-cysteine, urea, thiourea, and guanidine-HCl treatments showed no change, but ${\beta}$-mercaptoethanol and EDTA increased rubisco activase activity. In conclusion, ESA inhibited the content of rubisco and promoted its activity, whereas promoted the content of rubisco activase and inhibited its activity. In addition, the content and activity of rubisco and rubisco activase inhibited by Cd were recovered by ESA. The activity of rubisco and rubisco activase by Cd and ESA was inhibited by the denaturant and the recovery of ESA inhibited by Cd was lost by the denaturant.

카드뮴(Cd) 하에서 기내 배양된 담배의 생장과 Rubisco/Rubisco Activase에 대한 Ethylsalicylic acid의 영향 분석

카드뮴(Cd)에 의해 유도되는 담배의 생장과 rubisco/rubisco activase에 미치는 ESA (ethylsalicylic acid)의 효과 및 이에 대한 변성제의 효과를 연구하였다. 담배기내 배양에 대한 ESA의 최적 농도를 찾기 위해, $10^{-6}$-10 mM ESA를 처리하여 배양시킨 결과, $10^{-4}$ mM ESA에서 생장이 가장 높게 나타났다. 최적농도인 $10^{-4}$ mM ESA와 0.2 mM $CdCl_2{\cdot}2.5H_2O$를 사용하여, 대조구, Cd 처리구, ESA 처리구 및 Cd와 ESA 혼합구에서의 담배의 생장을 측정한 결과, ESA 처리구의 생장이 가장 좋았으며, Cd 처리구의 생장이 가장 저조하였다. Rubisco/rubisco activase의 함량과 활성을 측정한 결과, 두 가지의 함량과 활성 모두 Cd 처리구가 가장 낮았으며, ESA 처리구에서는 Rubisco와 rubisco activase의 함량이 감소되었고, 활성은 증가하였다. Guanidine-HCl 처리를 제외한 L-cysteine, urea, thiourea, ${\beta}$-mercaptoethanol, EDTA에 의해 rubisco의 활성이 억제되었으며, L-cysteine, urea, thiourea, guanidine-HCl 처리구에서는 rubisco activase 활성이 변화가 없었으나, ${\beta}$-mercaptoethanol과 EDTA는 활성을 증가시키는 것으로 나타났다. 결론적으로, ESA는 rubisco의 함량을 억제시키고 활성은 촉진시키며, rubisco activase의 함량은 촉진시키고 활성은 억제시켰다. 또한 Cd에 의해 저해된 rubisco와 rubisco activase의 활성이 변성제에 의해 저해되었으며, Cd에 의해 저해된 ESA의 회복이 변성제에 의하여 상실되었다.