摘要
为了确定Ca2+信号途径是否参与、在哪一时期参与稻瘟病菌分生孢子萌发及附着胞形成过程的调控,用四种可从不同位点阻断Ca2+信号途径的抑制剂分别处理分生孢子,观察抑制剂对孢子萌发及附着胞形成过程的抑制作用。结果表明:Ca2+螯合剂EGTA、Ca2+通道抑制剂Verapamil、抑制磷脂酶C活性的抑制剂U-73122、影响钙调素与钙调素依赖蛋白激酶作用位点的抑制剂KN-93,随着浓度的增加,对孢子萌发和附着胞形成过程的抑制作用明显增强;同一浓度下,抑制剂对附着胞形成过程的抑制作用大于孢子萌发过程;抑制剂影响孢子萌发和附着胞形成过程在萌发早期(1~4h)最有效;在完全被抑制、不能萌发的孢子内出现了许多颗粒状囊泡;抑制剂可使附着胞形态明显变小甚至不能形成。以上结果表明钙信号途径参与了稻瘟病菌孢子萌发及疏水条件下附着胞形成过程的调控。
Magnaporthe grisea,the causal agent of rice blast,forms a dome-shaped melanized infection structure,an appressorium,to infect its host. Environmental cues that induce appressorium formation by this fungus include hydrophobicity and hardness of contact surface,and chemicals from the host. To elucidate if the calcium signaling pathway is correlated with conidium germination and appressorium formation induced by hydrophobic surface in M. grisea,conidia were treated by four kinds of inhibitors. Microscopic examination and statistical data showed: (ⅰ)EGTA(100mmol/L),a chelating agent selective for Ca2+,Verapamil (270祄ol/L) which could block Ca2+ channels,U-73122 (7祄ol/L),an inhibitor of phospolipase C,KN93 (62祄ol/L),a selective inhibitor of CaMK could inhibit (50%) germination and appressorium formation. (ⅱ) Under the same concentrations of inhibitors,appressorium formation was inhibited more strongly than conidium germination. These inhibitors,except EGTA,caused the formation of small and abnormal appressorium. (ⅲ)These inhibitors inhibited strongly conidium germination and appressorium formation in early phase (1~4h). (ⅳ)There were some roundish vesicle in the conidium inhibited completely. These results strongly suggested that Ca2+ signaling pathway was involved in conidium germination and appressorium formation induced by hydrophobic surface.
出处
《菌物系统》
CSCD
北大核心
2003年第3期457-465,共9页
Mycosystema
基金
国家"863"计划资助项目(No.2002AA241311)
关键词
抑制剂
孢子萌发抑制率
附着胞形成抑制率
附着胞形态
Inhibitor,inhibition of germination,inhibition of appressorium formation,morphology of appressorium
