The primary action site of the suppressor from

PINODESA豌豆病原菌的抑制子和激发子对豌豆防御性反应的ATPase和信号转导的调节。在豌豆拟孢子萌发液中，该菌分泌一个多糖激发子(分子量约为70,000)和糖肽抑制物来抑制豌豆的防御反应。最近，抑制素A和B的结构分别被确定为GalNAc-Ser-Ser-Gly和Gal-GalNAc-Ser-Ser-Gly-Asp-Glu-Thr(植物细胞物理33：663-667,1992)。虽然这些抑制物抑制了豌豆中主要的植物保鲜蛋白pisatin的产生，但只有抑制素B在体外抑制了ATPase的活性。分析了两个抑制物和11个合成肽对豌豆质膜ATPase活性的作用方式。抑制素B和8种多肽对该活性有抑制作用。根据ATPase抑制方式，将它们分为竞争性、非竞争性和非竞争性…三组更多的是两者兼而有之。其次，用激发子和部分纯化的抑制子(包括抑制素A和B)研究了真菌信号在豌豆防御反应跨膜信号转导中的作用。在体内和体外，激发子分别在5秒和30秒内快速激活了与多聚磷脂酰肌醇(PI)代谢相关的几种酶，特别是磷脂酰肌醇和磷脂酰肌醇-单磷酸激酶，以及磷脂酶C。然而，伴随的抑制子的存在抑制了这些激活。K252a、新霉素或原钒酸等几种抑制pisatin产生的药物也阻断了激发子诱导的pI代谢的激活。这些结果表明，在豌豆植物的防御反应诱导过程中，PI代谢的激活是必不可少的过程。PI代谢的代谢物PIP2提高了ATPase的活性，而PLC的抑制剂新霉素则降低了它的活性。另一方面，P型ATPase的抑制剂原钒酸抑制了PI代谢。这些发现强烈地表明，ATPA之间的“串扰”较少

REGULATION OF ATPASE AND SIGNAL TRANSDUCTION FOR PEA DEFENSE RESPONSES BY THE SUPPRESSOR AND ELICITOR FORM MYCOSPHAERELLA PINODESA pea pathogen, Mycosphaerella pinodes, secretes a polysaccharide elicitor (MW = ca.70,000) and glycopeptide suppressors for defense responses of pea plants in its pycnospore germination fluid. Recently, the structures of two suppressors, Supprescin A and B, were determined as GalNAc-Ser-Ser-Gly and Gal-GalNAc-Ser-Ser-Gly-Asp-Glu-Thr, respectively (Plant Cell Physiol.33 : 663-667, 1992). Though these suppressors inhibited the production of pisatin, a major phytoalexin of pea plants, only Supprescin B inhibited the ATPase activity in vitro. The mode of action of two suppressors and the eleven synthesized peptides on the ATPase activity in isolated pea plasma membranes was analyzed. Supprescin B and eight kinds of peptides inhibited the activity. They were classified into three groups in a manner of ATPase-inhibition such as competitive, non-competitive and a m … More ixed type of both. In the next, the effect of fungal signals on the transmembrane signaling for pea defense responses was investigated with the elicitor and a partially purified suppressor including Supprescin A and B.In vivo and in vitro, the elicitor rapidly activated several enzymes associated with polyphosphoinositide (PI) metabolism, especially, phosphatidylinosotol- and phosphatidylinositol-monophosphate kinases, and phospholipase C with 5 and 30 sec, respectively. However, the concomitant presence of suppressor inhibited these activations. Several inhibitors for pisatin production, such as K252a, neomycin or orthovanadate, also brock the activation of PI-metabolism induced by the elicitor. These results suggest that the activation of PI-metabolism is an indispensable process during the elicitation of defense response of pea plants. A metabolite in PI-metabolism, PIP2, enhanced the ATPase activity and an inhibitor of PLC, neomycin, reduced it. On the other hand, an inhibitor of P-type ATPase, orthovanadate, suppressed the PI-metabolism. These findings strongly suggest that a "cross-talk" between the ATPas Less