培养介质pH和EGTA对水霉(Saprolegnia ferax)菌丝细胞肌动蛋白的分布与结构的影响  

EFFECTS OF pH AND EGTA ON DISTRIBUTION AND STRUCTURE OF ACTIN IN HYPHAE OF SAPROLEGNIA FERAX

作　　者：袁生[1] 窦洁[1] 陆玲[1] 薛绍白[2] 

机构地区：[1]南京师范大学生物系,南京210097 [2]北京师范大学生物系,北京100875

出　　处：《实验生物学报》1997年第4期391-401,共11页Acta Biologiae Experimentalis Sinica

基　　金：国家自然科学基金[No.39670375];国家教委优秀年轻教师基金[No.1993(436)]~~

摘　　要：菌丝在pH 5.0—8.0介质中维持顶端生长,Rhodamin-phalloidin荧光探针显示在菌丝顶端都存在F-actin的“帽子”结构;加入EGTA到培养介质中不影响菌丝的顶端生长和actin的“帽子”结构。值得注意的是:菌丝的Rhodamin-phalloidin荧光强度大小与菌丝顶端生长速率成正比;在含有或不含有EGTA的pH5.0培养条件下,菌丝的生长速率均很低,且后部颗粒状的荧光斑点消失;在pH 3.0-4.0培养介质中菌丝生长停止,不但F-actin“帽子”结构消失,整个菌丝荧光也变得非常微弱无法观察,提示酸性pH可引起F-actin的解聚,从而导致生长速率下降甚至生长停止。Hyphae could remain tip growth in pH 5.0-8.0 medium and showed a F-actin "cap" explored by rhodamin-phalloidin in hyphal tips; EGTA adding to the medium did not affect the tip growth and the actin "cap" structure. It was noted that tip growth rate of hyphae cultivated in pH 5.0-8.0 medium were proportional to the fluorescence intensity of rhodamin-phalloidin actin; hyphae cultivated in pH5.0 medium with or without EGTAhad a lower growth rate and lost of fluorescent plaque in the lateral aerea of hyphae: hyphae cultivated in pH 3.0-4.0 medium no longer grew, and appeared absent of actin "cap" in the apex and very dim fluorescence intensity in the whole hyphae. which implied that acid pH could induce depolymerization of F-actin so that it reduced or even stop hyphae tip growth.

关 键 词：肌动蛋白 PH 钙离子 顶端生长 水霉 

分 类 号：Q949.323.2[生物学—植物学]