Cell Biological Studies on Growth and Development Effect of$Ca^{2+}$ and polyamine of $\beta-glucan$synthetase activity in carrot root protoplast

생체생장에 관한 세포생물학적 연구 당근 뿌리의 원형질체에서 polyamine과 $Ca^{2+}$이$\beta-glucan$ synthetase 활성도에 미치는 영향

The effect of polyamine, Ca2+ and calmodulin on GS ($\beta$-glucan synthetase) activity was studied in Daucus carota root. The Ca2+ is shown to have no effect on the GS activity whereas the GS II activity is increased in response to increase in concentration of the Ca2+. When the protoplasts are cultured, for 4 days, the GS II activity increases as a tunction of time and reachs a maximum after 3 days at a time when the network of cellulose microfibrils is known to be synthesized. The effect of the Ca2+ and 1mM spermine on the GS II activity turns out to be synergistic, especially more synergistic at lower concentration of the Ca2+. The GS II activity seems to be enhanced by the Ca2+. The GS II activity in the protoplast treated by the calcium channel blocker, verapamil, turns out to be lower than that of the control. Cumulative results suggest that the Ca2+ stimulates the cell wall regeneration via enhancement of the GS II activity responsible for synthesizing the cell wall component throught synergistic effect with spermine.