过氧化氢对蚕豆气孔运动和质膜K^+通道的影响  

Effect of Peroxide Generation on Stomatal Movement and K^+ Channel on Plasma Membrane in Vicia faba Guard Cell

作　　者：安国勇[1] 宋纯鹏[1] 张骁[1] 荆艳彩 阳冬梅[2] 黄美娟[2] 周培爱[2] 吴才宏[2] 

机构地区：[1]河南大学生物学系,开封475001 [2]北京大学生物膜及膜生物工程国家重点实验室,北京100871

出　　处：《植物生理学报（0257-4829)》2000年第5期458-464,共7页Acta Phytophysiologica Sinica

基　　金：国家自然科学基金;北京大学生物膜及膜生物工程国家重点实验室共同资助

摘　　要：不同浓度H2 O2 可使蚕豆 (ViciafabaL .)叶片气孔关闭 ,抑制气孔张开 ,10mmol/L的H2 O2 最有效 ,10 μmol/L的H2 O2 仍明显使气孔关闭。且 10 μmol/L的H2 O2 抑制气孔张开作用能被EGTA所消除 ,表明Ca2 +参与低浓度H2 O2 使气孔关闭的过程。 2mmol/L的H2 O2 可使质膜内向K+通道电流明显减小 ,而外向K+通道电流显著增加。因此 ,H2 O2 促进蚕豆气孔关闭主要是通过抑制K+通过保卫细胞质膜内向流入 。H 2O 2, a species of active oxygen, at 10 mmol/L could induce stomatal closure and inhibit stomatal opening(Fig.1). The effect of H 2O 2 inducing stomatal closure could be 10 mmol/L V C, but V C in lower concentration(1 mmol/L) had no such effect(Fig.2). EGTA (chelator of Ca 2+ ) and phenothiazine(antagonist of calmodulin) had no effects on the H 2O 2 induced stomatal closure(Fig.3), but they could abolish the effects of 10 μmol/L H 2O 2 on the stomatal aperture in Vicia faba (Fig.4). In addition, the K + channel current in plasma membrane of guard cell was recorded by whole cell configuration of patch clamp. On adding 2 mmol/L H 2O 2, voltage clamp measurements showed that the inward K + channel current significantly decreased 5 min after H 2O 2 treatment, and the outward K + channel current rose markedly about 30 min after H 2O 2 treatment(Fig.6). This suggests that H 2O 2 induced stomatal closure may be the result of the inhibition of K + uptake and the evocation of K + release through K + channels on plasma membrane in guard cells.

关 键 词：蚕豆 保卫细胞 H2O2 K^+通道 膜片钳 

分 类 号：Q945[生物学—植物学]