抄録
Lethal effect of Al on cultured tobacco cells was investigated by treating tobacco cells (Nicotiana tabacum L. cv. Samsun) at the logarithmic phase of growth with AlCl3 in a simple calcium medium containing 3 mM CaCl2 and 3% sucrose. Propidium iodide and Fluorescein diacetate staining revealed the maintenance of the integrity of the plasma membrane even after 18 h of Al treatment. However, BCECF-AM and Neutral red staining showed the evidence for the loss of function in the vacuole. Pre-treatment with Caspase-1 inhibitor, Ac-YVAD-CHO, significantly reduced the Al-induced vacuole collapse in tobacco cells. Furthermore, a strong negative correlation was found between the ratio of collapsed protoplasts scored after 18 h of Al treatment and growth rate of tobacco cells 6 days after post treatment. These findings suggest that Al can cause vacuole collapse before final death and caspase-1 activity might be involved in Al-induced cell death process in tobacco cells.
