ACC和IP_3对月季花发育过程中细胞质Ca^(2+)浓度的影响 (英)

The Effects of 1-Aminocyclopropane-carboxylic Acid and Inositol-1, 4, 5-trisphoshate on Cytoplasmic Calcium Concentration During Chinese Rose Petal Development

采摘现蕾、初开、萎蔫和脱落期月季花花瓣，纯化原生质体。利用Ca2+荧光指示剂Fura－2－AM，分别用SpexF212Fluorolog和数字分析系统，建立了植物细胞胞质自由Ca+浓度的测定技术。结果表明，月季花现蕾、初开、萎蔫和脱落时期，胞质Ca2+浓度分别为8、62、12和15nmol／L，花开放时刻，[Ca2+]c有一个突然升高，然后又回到静息态。ACC1mmol／L处理，使[Ca2+]c迅速增高，并促进花的开放。推测胞内静息态Ca2+浓度为8～15nmol／L，[Ca2+]c改变控制着花的开放运动；但是衰老期[Ca2+]c没有增加，可能由于衰老是一个缓慢过程，[Ca2+]c增加只发生在衰老的启始阶段。IP33．6μmol／L处理原生质体，可降低[Ca2+]c，钙通道阻塞剂La3+阻止这种降低，IP3可能作用于质膜上的Ca2+通道。因此，膜磷脂代谢在胞内钙稳态控制中起着重要作用。

Protoplasts from Chinese rose(Rosa chinensis Jack cv. Zirong) petals at different development stages were loaded with fura-2-2AM to measure [Ca2+]c. The fluorescence of frua-2 was measured at 450 urn using a Spex F212 Fluorolog with excitahon at either 340 urn or 370 urn. Fluorescence raho photometry technique was used to check the method. The resultS indicated that [Ca2+]c, at the bud, flowering, wtlhng and senescing stabes were 8, 62, 12 and 15 nmol/L, respeChvely.When cut flowers were treated with ACC 1 rnmol/L, [Ca2+]c, rapidly increased to 108 nmol/L in conjunchon with the Premature Opening of the flowers, and no change occurred in the value of [Ca2+]c. during senescence. When the Protoplasts were treated with 1P33. 6μmol/L, [Ca2+]c. decreased, especially at the opening stabs, but aams kind of ac2release could be inhibited by introducing La3+, a potent blocker of Ca2+ channel, into the cell, These results suggest that the opening of flowers can be induced by a rise of [Ca2+]c from a relahvely constant resting level of 10 nmol/L and lP, can affect the Ca2+ channel achvity in the Plasma membrane.