作　　者： ; ;

机构地区： 华南农业大学

出　　处： 《植物生理学报（0257-4829)》 1994年第2期179-184,共6页

摘　　要： 鸡蛋果叶片照光１５ｍｉｎ后，其成长叶ＰＫ和ＰＫｃ活性降低，幼叶ＰＫ和ＰＫｃ活性提高。鸡蛋果成长叶ＰＫｃ受［ＡＴＰ］／［ＡＤＰ］比值调节，受ＤＴＴ轻微抑制。ＤＴＴ和生理浓度ＡＴＰ对鸡蛋果幼叶ＰＫｃ活性无明显影响。这表明鸡蛋果成长叶ＰＫｃ光下受抑制可能与光下［ＡＴＰ］／［ＡＤＰ］比值提高有关。 The effects of illumination on thePK and PKc activities were examined.The PK and PKc activities in matureleaves of Pasiflora edulis decreased 27%and 19% respectively, while those inyoung leaves increased 12% and 14 %respectively after illumination for 15min (Fig. 1 -- 2). These results wereconsistent with the rePOrt from our Laboratory that glycolysis of mature Peanutleaves was inhibited and that of youngleaves was activated slightly by illumination (Zhang and Li 1991 ). It wasconcluded that PKc was one of the lightmediated regulation steps of EMP pathway in green plant tissues.The PKc in mature leaves was inhibited to a large extant by ATP thanthat in young leaves. The PKc activityin mature leaves was inhibited by ATPat its physiological concentration, whilethat in young leaves was not affected(Fig. 3). This indicated that ATP hadno effect in vivo in young leaves.The resultS also indicated that thePKc activity in mature leaves was regulated by the [ATP]/[ADP] ratio (Fig.4 ). The PKc activity decreased rapidlywith an increase of the [ATP]/[ADP]ratio up to 5, but only slowly when theratio was above 5.DTT, a reducing agent, had aslight inhibitive effect on the PKc activity in mature leaves, but no effect onthat in young leaves (Fig. 5￣ 7 ).Based on these observations, wesuggest that the depression effect oflight on PKc activity in mature leaves isdue to the increase of cytosolic[ATP]/[ADP] ratio related to photosynthesisand the cytosolic reductant(s) producedunder light. The mechanism of light activation of PKc in young leaves remainsunknown, and is probably differentfrom that in mature leaves.

关 键 词： 绿色组织 光 丙酮酸激酶 鸡蛋果

领　　域： [农业科学] [农业科学]